Richard, any chance of redoing this test on a stock ci 427 LS7 with updates on the heads? I lot of changes have been made within this market over the years and 99% of the LS7 based engines are going to be 427 ci. Would love to see this done with a 102mm NW TB and MSD intake as well... again being more of the norm.
@@dennisrobinson8008 With a good cam and either Mast 305 or BR7 300 heads, you can easily get into four digit power with a large inch LS 268/286 split, 114+6 and .799 lift. Oh, and that is done on hydraulics...
427ci isn't enough to actually test them lol but the results are the same just like if u test a 4.8, the results are the same on a 6.0 just a higher starting point for the numbers, and tq coming earlier rpm. It's not hard to guesstimate 427 numbers
Thanks so much for doing these videos! Would love to see this video done with a stock bottom end ls7 427 and with some other heads like a set of greg good ls7 heads, trickflow genx 260(what I have), prc 280 and so on to see what option for us stock bottom end ls7 guys makes most sense
Can’t believe it took me a year to watch this. Great test glad to see so many LS7 cylinder head options tested back to back. Looking through those numbers it looks like the exhaust ports were the dictator on the best power levels for this combination. Would be awesome to test this with a big solid roller.
You can run adapters to fit an ls3 manifold to these heads. Run a factory Ly6 truck rec port manifold and make all the torque, you would really have to know your stuff to spot the manifold and adapters but if you could sneak 500 cubes on e85, there is potentially 700hp with roughly a factory outward appearance.
Nice job showing the different heads, since you weren’t going for max effort but just trying to show the differences in the heads, I think you accomplished that. Would be cool to see a follow up video highlighting different cams. May be cost prohibitive and time prohibitive to have to change valve springs over and over. In any case, good job and keep it up😁
I love the comments from the 427 guys telling you how high to rev the 495. Apples and oranges, like trying to compare the displacement of a 346 or 364 to a 427.
The camshaft used was a medium sized grind for that size engine so definitely not small. I would have used a 265/279 114lsa. Also Richard you really need to rev those ls7 heads out to at least 7500rpm as this is where they shine and are in essence a big bore high rpm race head. I have had experience with these in my heavy car and did not like them because at any rpm under 4000rpm they dont have a lot of torque to get the car moving and under the curve power is average at best. But from 6000rpm+ they start coming to life. A solid roller would also be a great idea. Using comp cam ls street solids you would need a 272/286 cam. There is a member on corvette forum who made 800hp with an ls 454, mamo reworked ls7 trickflow heads, Mamo ported MSD, 13:8.1 compression, 264/276 112lsa +3 comp cams steet solid roller. I still think Richard, you should be the one to settle the trickflow 245 vs AFR 245 head debate which has been going on for years. Most prefer the trickflows because they claim they make more power but from what I have seen it is the AFR that comes out on top. Get an engine at least 427 cubes. Make sure everything is the same with the only change being the heads so the test is fair. I really liked this test too.
agree on this....and the interesting test on afr vs tfs 245......more real world-- nice test for a 427 ...12.5 to 1....nice solid roller (270-276) with a 950-1000cfm 4150.. or even a pump gas 11 to 1 427 with above roller....LOL These numbers are pretty big....on hyd roller. makes a real low maint street bruiser, but the stock heads can handle that pretty well. need another 1000 rpm for the better heads to show themselves. These LS engines run well....but as Ford guy, the windsor isnt too far behind....but you need a dart block and good rotating assembly 700 on a 427 is fairly easy....and thats not a canted valve head. another great test. there is another great test.....427-460 sbf with higgins-or D3 heads (12.5 to 1 with a decent roller---270-278) and you will find 850hp and streetable. nice channel! well presented, clear and no BS.
We're going to need you to slap a couple turbos on that bad boy, then we wont really care about the cam, right? This would have been stellar and a lot more work to run each set of heads with a huge solid roller too. I would love to see something like AJPE heads compared to the regular heads.
Richard, I want to thank you for bringing up the LS7 heads test. That was Awesome!!! I would like to see the same engine size you used to test the ls3 heads. This way we can see the difference between one and the other. Thanks!!!. Keep it up bro! 😎👍
More great info! I don’t see flow numbers at 0.800 lift, were any of these heads tested there? Also, I was hoping to see what TFS GenX 260s were going to do. As to your questions, this is big block territory and I’d think more lift (like 0.750 or 0.800) would be good. Thanks for the coverage even if this is way out of my budget!
As to the one comment it is definitely big block territory on the intake but the exhaust cfm on big blocks are low to mid 300’s on a good cnc big block head , but absolutely impressive heads and motor .
Had to re-watch this now that I'm looking at an RHS build. I'm entirely jealous you got to punch it out to 495 cubes. I wonder if a big dry sump will put in some power by cutting windage. I was thinking of running a bunch of stages, then a tank that hangs off the front of the engine by being tapped into a dirty dingo bracket setup. No more pickup tube. Just some AN lines that go to the tank so it gravity primes. Dump the vapors down the header. I clicked together some other combinations. One was a 454 that had tough 1.304" pistons. I wonder if the smaller displacement will shift the parameters up enough such that it works better with the intake manifold and makes more power by dumb luck. If not, it's perfect for spray or boost.
I sent out my LS7 heads to Advanced Induction a few weeks ago. Was hoping to see AI’s 280cc heads in this video but regardless thanks for the comparison 👍🏻
@@bigbrown2690 I did not use RPM, but they seem like they do nice work. I also used a BTR-4 cam. It's pretty rowdy, doesn't like 6th gear.. I have QTP cutouts, and it's rude!
Rickybobby 03 I’m subscribed to them, I know they flow well and can make great power but it would’ve been great to see how the AI heads perform against others.
Richard you sir are putting in some work great video. That combo would be great with 2x200 shot of gas on the street 1200hp on a 10.5 slick hard to beat
I have a set of the COPO 427 LS7 heads, destined to live underneath a 2.9L Whipple. Everything is better with BOOST! I'm guessing the COPO head is very similar to the CNC GMPP head.
Hey richard, have you ever tested, between stock vs polished (no ported), on intake or heads Did the rougher surface, mix air and fuel better for carbureted engine?
Richard is right about this. The discussion is years old now but your going to want to have the intake system that flows the most air and a carb that works properly. You can get some fuel puddling issues if the surface finish is too rough and has a pattern that is parallel to the direction of flow. There is turbulence on the port wall that causes a boundary pressure region that causes the fuel to drop out of suspension or deposit. There is basically no such thing as a port that is too smooth. When you get fluid flow in the port making tiny eddies along the walls, the pressure in the area goes up, the fuel condenses and then can't change direction as fast as the air and sticks to the side of the port. Think if you had an oversize valve seat cut without blending it into the port. The air would be flowing along nicely then it would come to the edge of the cut, slow down and crash into the square edge of the valve cut. It's the same thing that happens when the back window of an SUV or the tailgate of a pickup gets dirty. The flow makes a quick 90° turn and the dirt continues strait into the glass because the direction of flow has changed. If you ever notice how dirty the doors of a van body highway trailer get, its for the same reason. There are some guys that still claim that rough cut or raw burr finish is the best, and usually it's really good if it's a cnc job with tiny feed rates. Both Wilson manifolds and SME fabricate completely billet manifolds with no design limitations. Wilson builds billet intakes for pro outlaw twin dominator big blocks, and even though the ports aren't polished, they are almost mirror smooth right off the cnc.
Hi Richard. I’m looking to use a Dart LS Next block to build a torque monster for my 2015 Sierra to pull my travel trailer. But, there’s not much info around about stock heads heads. I thinking about the 706 heads for torque but will the engine be starving for air? Any input on this? LS7 block 706 Heads?? 4.100” Stroke 9.5:1 pistons Lunati Voodoo RV cam Trailblazer SS intake
For that size bore you really need a better head. One of the BR3 or BR7 offerings would be a good choice. Just buy them from someone who can put in a proper durable valve job and set them up for what you are planning on doing. A guy like Eric over at Weingartner Racing seems to really know his BR heads.
This is an awesome test Richard. But I wish I could see what these heads did down low below 3000. Im debating putting some After market heads on an otherwise stock LS7 and wanted to see if it would retain close to stock characteristics down low driving wise or if with putting a set of these heads on you lose something down low. I love how the stock LS7 drives with so much torque down low. Don’t wanna lose that. Was just thinking of putting heads on to possibly to remedy the valve issue.
I thought that as well. The factory ports are also designed for only 428 cubes and 510hp (without accessories and with headers like Richard tests, they would be closer to 570-590). They also have that mass produced stigma where gm got to where they needed to be and stopped developing the head. For all the production limitations, it might not be worth much, even the best performing head here might only add 10-15hp to a production engine, with the factory camshaft.
The components listed here, K1 makes awesome cranks, can take more rpm than the ring pack. It's the hydraulic lifters that will limit you every time. This is begging for a solid roller, 8000 is about as fast as your gonna want to spin something with a 4.5" crank but this combo would probably make another 100hp with a solid cam and bigger headers.
That mill in this vid will support 7500. You just need a bit more cam. Add the Cam Motion Nitrous LLR cam with .765 lift and 267 duration and you're easily there.
Theres a long standing debate between which is better of ported LS3 vs as-cast LS7.....If I were you I'd stick with ported LS3 so you don't have to deal with valve-cylinder wall clearance.
@@timothybayliss6680 True,,, was thinking bout building a grenade engine as i traded a 1st gen sbc 350 for this Lq9 in Great Shape out of a Escalade to stuff in my Vega
@@tomnekuda3818 Its my half shafts I'll likely be breaking (again). Ive got my Novi 1500 spinning at 55k rpm at 7k this time with no restrictor. Should be good for 950 flywheel or so. Managed to touch ring ends in number 7 on my original LS7. Several times at that. Then the piston left decided to leave the rings behind. Displacement on demand right?
Richard, I need to replace engine trans and transfer case on 2013 suburban. I have driven crap out of it. Pulled to heavy trailers. If I buy a GMC or Cadillac SUV with 6.0 or 6.2 how hard is it to install? Do electronics have to be swapped. Or do I drive suburban off cliff? And buy new one. A good copart rig is running in $6k range
What do I think? Holy shitballs! Things have really changed since 1988. Car companies have got enthusiasts, and not bean counters, running their engine development teams.
Thanks, as always you give outstanding tested information. Richard what is the effect of compression on turbo engines? I was always told you want less compression on turbo engines.
@@richardholdener1727 Hi mate, id love to see more on this, the way i see it, compression is like camshaft, if every cam is a turbo cam is every compression turbo compression?
Richard I’m not bullshitting you when I say the set of lsa heads Greg good ported for flowed very similar numbers to the brodix and mast ls7 heads...... I would love a comparison of a set of heads from Greg good , Frankenstein , modern airflow dynamics. P.s I already know the winner
Hey Richard. I just bought a 351Windsor and I'm wondering what cam, carburetor and intake manifold combo would work good with stock hand ported and polished heads. In also going to be running short tube headers. I don't want to just go with a giant cam, but I also don't want to undercam it. Appreciate if you manage to find and reply to this. Maybe even make a video on the Windsor. Thanks!
Your heads will be a big limitation. You didn't mention your application, but amateur ported OEM 351W heads on a healthy shortblock would probably be best with an Edelbrock performer or performer RPM intake (or similar), a 650ish carb (750 will work but too big), and a cam with no more than about 220º @ .050. I'd think *REAL* hard before putting ANY money into stock heads when anything aftermarket aluminum will beat the pants off those stockers, and save almost 80lb on the front of your car.
Richard, how does stroking an LS engine affect the rod /stroke ratio? The 400 CI had a poor ratio of 1:48 creating a lot of side wear on the cylinders.
Hey Richard, we have talked before about my LSX454 in my Pontiac G8. I have 11.5 compression, ported factory LS7 heads with a 275cc intake runner and flow numbers that closely match the TSP head in this test. It looks like this was the same test you ran for your LS book? That book has been such a great help! Anyone reading this should buy it!I have a small cam for this size motor at 239/254 114 .660/.630 on a 1.8 rocker. Through a 6l80e auto it made 540rwhp, 525rwtq on a dynojet literally yesterday. Those numbers are SAE and uncorrected. Shop temp was in the 70s and humidity was high so I'm not sure how that would change things in a STD corrected format, or even SAE correcred. I am getting ready to toss in a bigger cam, and did look at the same cam you ran on this test. Do you think it would pick up an honest 20-30hp at the tires all things being equal? I'm trying to find the limits of this combo and know a bigger cam is a must. I do have a ported MSD intake which I know all the Corvette Z06 guys like, but maybe something with a bit shorter runner (MSD runner is about 9", Holley Hi Ram is about 6" for comparison) would also help this thing out. Have you ran any EFI intakes on an LS7 headed combo?
Hi Richard, it seems (not specifically from this test) that the smallest intake port volume....max flow being equal, will always make more power. Do you find this to be true in general?
Same thing was observed recently with the BBC heads test [both oval and square]. The smallest volume but highest flowing heads gave the best results thru the whole curve.
For the rpm. These are great numbers. Now i ask...if this combination was in a big block chevy. Lets say a 496ci, 13:1 with a cam of the same lift. Would you top these power numbers? And a similar power curve?
I looked back at a early bbc video. Seems thise test were about 100-150 hp less. Except the brodix head had a bunch more power below 5000. With all the videos. Iam seeing smaller more efficient ports create more usable power the big ports. Can you make a video just comparing exhaust comparisons. For instance...the sportman II heads had 200cc intake ports but the exhaust side restrictions hold them back. Same with oe bbc heads.
@@approachingtarget.4503 When you ask that question, you need to factor in which heads you are talking about. Are we talking a set of "bland" as-cast Dart 325 heads, a set of stock Gen VI ported heads, or say a set of Sniper X 375's? The first two flow less than the Mast and less than a BR7 273 and BR7 300 for sure. So in essence that would make less power. Now fit that same engine with a set of AFR 357's or a set of Darin's Sniper X 375's and things change. That said, if you were ever to make 800+ hp from a BBC, even a "small" 496 BBC, why only use .660 lift? If you make a setup like that, there are several things you should do to make it a better combination. Start by having the cam tunnel machined out to accept a 55 mm cam. That way you have some of the lobe geometry advantages of the LS. This also allows you to run more lift which the heads would like, while retaining an equally stable valvetrain compared to a stock sized BBC cam core with less lift. My point is that as you can see, there are a ton of variables. Put peanut port heads on the BBC and it will never make power while a good set of heads matched to the combination will ALWAYS, and I do mean ALWAYS make more power than the equivalent LS. This because as Richard told you, there are always a BBC head which can make more power than any LS head. At the end of the day the LS is still "just" a small block with what ever limitations that brings into the equation.
Richard I have an lq9 I’m planning on port and polishing a set of heads for it what do you recommend I have a set of 241, 243, 317 and 706 heads I have an isky 598 lift 236 duration and 113 lobe Separation out of all those heads what would be best for high rpm application this engine is going into a drift car
Hello richard could you do an other guys build on a vw aircooled engine thanks. I've been looking to upgrade my VW with cb performance cnc ported cylinder heads.
Not an engine man. I do think a larger cam would give a better picture of this engines capability. I would have expected to see something in the 0.725-0.750 range for a na motor of this size and caliber. Duration maybe a few degrees more duration. Yes I know now we may be getting into the roller rocker range. Increased lift would probably require more spring for the valves. I’m sure the folks at T/D or Jessel could help with this question on the rocker arms. All in all a great test. Let’s everyone see the potential of the heads tested. Thank you for the video. You keep making them and I’ll excel at watching them.
You can get lobes that will provide .800 lift on hydraulics. That puny .660 number was a major brainfart. People are making 750 hp with 240 degrees of duration and less lift on416-427 engines. That 495 was completely choked off by that cam. Would have been great with the same duration but lift in the .750-.800 range.
Cam: More lift, 0.750" or more and Tighter LSA, bring on much better torque with the single plane. Maybe 10 degree more duration. IMHO I'm no expert though. Like you say it's what was bottom of the page back in the day.
Unless you kick the lift well into the 800's, there's little need for more duration here. I'd say with 259, just lift it to .799 with hydraulics. If you run 270'ish duration, you are already into max effort territory so just get all the lift the heads will allow.
He mentions in the video the block. To fit the 4.5 stroke crank you need a tall deck ls block. The sleeves in it give you the 4.18 bore or what it had. The limit for a production block is a bit less, guys really won't run more than a 4.25 crank and you can sleeve them out to 4.185. I think that gives you 468 cubes. Any production aluminum block is good for this and there is a bunch of gen4 al 5.3 blocks in crummy suv and things nobody cares about that work when all you want is a block. It's lots of work but the payoff is huge. You don't see to much of it for the street though because the factory blocks are so tough and you can make so much power with boost.
@@roscoetippetts8619 vortec 8100 in the 3500 trucks is a Gen 7 big block chevy (spread-port head design), not LS. The only similarity between LS and gen 7 BBC is firing order. Otherwise the two don't share a single common bolt
Forged 370 cid, milled LS3 heads with .660 springs, vs 317 vs 243 vs Mast vs TSP, etc., single plane, accufab TB with long tubes... The "affordable" combo. The cam was WAY too small for 495 cubes imho.
Just needed a ton more lift. If 820 hp was the goal, this cam was the completely wrong way to go about it. There's no problem in lifting .750" on a hydraulic and duration could have been in the mid to high 24X's and it would have been better overall. With that duration, lift should at least have been 750 if not 800.
The Mast heads biggest advantage looked to be in the exhaust flow. Be interesting to see if that advantage was that large in a 416ci, or 427ci engine, as there would naturally be less exhaust. the SDPC heads look pretty damn good. Are they proprietary castings, or are they reworked GM heads?
I wish you could make an in-depth video of the differences between boosting a gm lsx 427 with ls3 heads versus ls7 heads. What the advantages and disadvantage be. Of course for N/A, LS7 heads are the way but i'm curious about boost.
Where are the MBE/Dart 10 degree heads? JK, I know that's a major architecture change but would love to see a set on this size motor. With the 'right' camshaft of course. 😄
@@richardholdener1727 Ah.. time stamping. Think they came out around the same time as this video. Looks promising.. those and the Edelbrock "Race" heads. Thanks all the same.. really appreciate what you do here Richard. 🤜
Would have liked to see the TFS GenX in there ... or better yet, the MMS265 version which I am told go over 400 cfm below .6 lift and do it with a port smaller than the as cast LS7.
Mamo seems like a god of the high ports. I've seen one thread where the claimed numbers were 387 at .600 and 404 at .700. That's a couple years old now and he might have improved his cnc program. There was a time more than ten independent shops all had Mamo top end ls7 as their highest na horsepower for any ls7 engine. He really seems to know what he is doing.
You need to get out more. If you really want to see what can be done when it comes to 12 degree LS7 style heads, you need to get down under and visit CID. Mamo knows his stuff but he is not the best of the best, especially when it comes to LS heads. As for Mast 265 heads flowing 400 @ .600? No, not now, not ever. I've seen a set that had been properly worked over with good valve jobs, a more efficient short side, and a few other little tricks, and it was about 360 @ .600. Heck even Mast claim 370 @ .600 and those numbers are a bit on the happy side let's just say. The best small port LS7 style head I have ever seen was a hand ported as-cast BR7 that had been reworked to about 260. It was in the low 370's from .600 to .800 and never got above that, but never dropped off either. I believe it was done by CID in Australia as well. Go and ask Darin Morgan, Tony Mamo and even Horace Mast about CID, and you can be pretty sure that when it comes to LS7 heads, they know that's where it's at. Reality is this. Tony Mamo has kind of become a household name because of his association with AFR so many know of him, but while he's good at what he does, there are definitely head porters I'd choose before him. Go and see what moves in the wonderful world of custom ported heads and custom program CNC heads, and you'll find that Mamo is not the guy those who really want the absolute best seek out. Again, he's good, very good in fact, but I don't think he's the "God of head porting" some seem to think he is. Anyhow, go and check out CID, they are the dogs danglies when it comes to LS heads. I have never seen any 12 degree LS head flow as good, not even my BR7 300's which have been ported and had a proper valve job done. And by the way, my BR7's which started life as the 300 CNC heads only just flow 403 @ .600 on a conservative bench.
I'm looking at avg hp/trq, as well as idle vacuum... other than that overall drivability, as it must be driven in traffic... whilst still kicking ass. Maybe odd, but that's what I'm looking for.
Not odd at all, I think we are all searching for the Jekyll and Hyde, but I am becoming convinced that (at least for N/A) what results in idle vacuum impinges on high RPM flow. Sort of like you have to leave something on the table on one end of the spectrum.
Really? Tell me you are writing that to make yourself look cool, please. Flame speed... Tell me again what determines flame travel speed and what we use to account for it?
It would have been interesting to put a set of solid roller lifters in for a couple pulls. Just to check for potential hydraulic lifter issues at high rpm.
I cant wait for my engine to get built. Ive got the rhs tall deck and the brodix 273. So glad you used these and put some concern behind me. You must live at the dyno shop?
RPM's? So how many minutes do you want to measure the revolutions over? It's one minute, not several. Revolutions Per Minute, Revolutions are plural, not minutes.
@@dennisrobinson8008 It would probably not have moved it all that far up. But what it would have done, was to massively increase power over the entire curve. With a .660 cam, those heads weren't even starting to breathe. You need to get into the 750-775 lift area to even see a real advantage of the head's .700 lift flow capabilities. If one goes into a solid roller, low lash or what ever, might as well run .850" of lift. .750-775" lift is easily done on hydraulics. That said, if the intake was 266 as suggested, I'd probably run 282 or 284 on the exhaust seeing we are dealing with LS7 style heads.
Surely Comp can grind a custom cam for you now. You have done more than enough for them. These catalog cams kill me and I know it was holding this combo back, just not how much.
@@indyrock8148 that's probably pretty close on power, there are guys making really close to or over 900 at the crank with huge solid rollers. It seems strange to me to have an aftermarket engine from top to bottom and still keep it under 7000rpm with a hydraulic camshaft. A couple hardcore guys are really close to 1000hp NA, but their setup is completely focused on runs 8 seconds at a time an 1320 feet. You could daily this if you eat nails for breakfast and have e85 local.
Anyone can order a custom cam from Comp. Just look in the master lobe catalogue and select the lobes you want with the LSA, ICL etc. They offer hydraulic LS lobes that goes to .800 lift these days.
I would of liked to see this test with a Dual plane intake , low rise intake . Big numbers up top everyone enjoys seeing including me but u would love to see some down low stump pulling grunt . Start the pull at 1,500 - 2,000 rpm and let it eat
If you build something to do that, nothing here is what you want other than the displacement. Nobody, and I do mean nobody would ever run full throttle at those rpm, ever. If you build a truck engine for hauling stuff, you are building something different. As long as you have more than one gear, and especially if you have a torque converter, there's zero reason to perform that test. As soon as you put your foot in it, it will rev up to at least 3000 rpm.
I reckon a solid with 270/280@050. 720 plus lift. These heads should make power to 8000 your running out of lifter at 6500,these heads are still yawning at that. I’m running a 260@050 hyd with a 1.7 rocker and tighten up the lobe centre like a 110/112. 115 is almost a blower grind, but I am an amateur!
Why lift at .720 with a solid when hydraulics go to .800? Have you ever built a high horsepower big cube LS7? I ask because your numbers seems to be those of someone who has a slight idea about what would make power in a 509 BBC 25 years ago, but not really what is possible with a big inch LS. Those cam specs for example, makes zero sense with any of these heads or the rest of that package. And if you wanted to take the duration all the way to 270, lift it to .850 and give it 288-290 on the exhaust with 113-114+4 on the LSA. Those Mast and BR7 heads need lift, lots of it.
It might be interesting todo 6.4 Hemi/Apache head, ThiTeck Heads, or one of those aussie DOHC straight 6 or a Rover SOHC engine....Id also be interested in seeing what ceramic coating the pistons/combustion chamber does on some old stock iron heads (as far as overall engine temp and hp). It might also be interesting to see a chassis dyno comparison with a Carbon Fiber Wheels and drive shaft vrs stock aluminum Rims/Driveshaft. Probably have todo a mustang
.660 lift and 259 intake duration on the cam. Probably lost 5-10% due to deflection, so we are achieving up the .600" lift numbers on the heads, maybe a little bit more. Very interesting you were able to get 800+ HP in this case.
@@richardholdener1727 Weingartner was a fan of more lift to overcome the deflection. The stiffer the spring and greater the rocker ratio the more deflection. th-cam.com/video/3SMMr4GQB8k/w-d-xo.html
@@dennisrobinson8008 Lol. Have you ever measured deflection on an LS? For starters, an LS uses a 55 mm core. That alone has a lot to say. 259 degrees of duration @ .660 lift? That's nothing, and I do mean nothing. Unless he uses spaghetti for pushrods and some kind of shitty Chinese rockers, there's little deflection here. Maybe .005"-.008". I helped a buddy who had some issues with small block, and it turned out to be a combination of crappy pushrods and not running a stud girdle. It was lifting in the .740 range with a solid roller cam, and he had chosen some cheap thin walled pushrods because he though light pushrods would be a great idea. With the lack of proper pushrods, not running a stud girdle, spring pressure for a healthy solid roller in the .260 duration range etc. we measured 0.023" of deflection which is a lot by the way. Installed proper pushrods and a shaft rocker kit. Deflection was almost gone. If anything, the .600" number is relevant for an entirely different reason, and that is because a cam with a .660 lift, will only lift that valve @ .660" for a split second as it goes over the nose of the lobe. This means that ,650" flow numbers are pretty much pointless in this case. Everything here happens from .620" ish and down, if not .600" depending on lobe geometry.
@@HorsepowerHeadquarters454 I would really like to see a nitro test. I don't think any dyno will reliably hold that much power. If you used a 5.3 with a blower cam and tuned it, then fed it 90% just to see what the difference in power is, it would be a really interesting. Running a cheap engine that your going to beat the bearings out of can still show some awesome results.
@@timothybayliss6680 that high of % it wouldnt last 1 pull. Youd be hard to get enough fuel in it though. Having run a mechanical injected bbc then added some nitro the fuel consumption goes through the roof and most people don't have enough fuel pump(s)
It seemed strange to me to run as much stuff as you could, but keep the hydraulic camshaft. 13.5 compression will keep this off the street unless you have e85 but how much was spent on this combo its screaming for more camshaft. The guys that run these combos hard will run solids to 850 lift and spin the engine fast enough to cause local disturbances to the weather. This was a really good test, it showed some discrepancies between parts like any test should, but it's almost impossible for me to believe that anyone running a completely aftermarket engine (block, rotating, heads) will still be running a hydraulic camshaft when a solid could add so much.
I know you have done a gen 6 BBC but any chance I could get some gen 5 peanut port love? See what the old girl will do with a cam! Intake! Headers and More!
@@richardholdener1727 just ordered a Holley 5 bar. Headed your way to the shop at Westech. Thanks for the great vids and I hope to see this sensor maxed out at some point... haha!
What should I do? I want 777 hp or tourque from a chevy engine. Can be a bigblock or ls... Any advice? I really want a 777&777 from a engine in my small eu box... And yes I am massively into numerology...
You can do it with either one. It's the money you are working with that is the factor. Even now in the days of boost in every motor the old saying of "no replacement for displacement" is still very true. If anyone disagrees look at all the serious street car guys. A 540 or 632 is considered "small" lol
Build an 800 HP engine and then restrict flow back to 777... or tell the dyno operator to adjust the correction factor until it computed peak is 777 on the nose and print the chart. (No two dynos are the same so peak HP numbers are sort of subjective).
Build any motor with boost like one of those junkyard 6.0 that Richard likes. Add boost and a controller and so long as you can get it to handle the 777 torque you can let it bleed off the excess boost on the high end so it only makes 777hp.
@@opieg7333 Lolz. I did cup car engine testing with GM back in the late 2000s. We had amazing test cells that were super premium with all the latest fancy pants equipment. We calibrated the dynos every 6 months, which included calibrating the load cell with dead weight, and then installing our "gold standard" stock 4.8L to verify everything was reading normally. Then Hendrick or BNR or RCR would bring an engine for us to test and when it showed 79x on our dyno, they'd scream and yell and tell us our dyno was wrong - that back home in North Carolina, their Superflow read 83x hp. There was no arguing with them, so I'd just calculate the multiplier needed to hit whatever number they wanted to see, and display HP/TQ that'd been multiplied by my offset. Always made me shake my head, considering we had a $10M test cell with all the best shit, and here I am "correcting" the numbers so they'd say what the customer wanted to see...
Since torque really isn't an issue here, I wonder what individual throttle bodies would do on one of these, or even a stock 7.0 liter engine but with the rest of the mods
Torque also means something in relation to drivability. A Harrop intake would be cool, but not sure there's a lot to gain other than looks. That Mast intake is really, really good.
@@AB-80X my point about torque is that the LS7 already makes mountains of it. When Harrop 1st came out with their ITB setup they put one on an LS7 then returned the engine bc of the intake and picked up 50 who on the top end. Now, that being said of course part of the gain was from just being tuned but it HAD to be returned cof the ITBs. Most of the gain was from the ability to breath better at high rpm. Not sure what it did to peak torque or the curve but with an engine this big in a street car it should be that big of a deal
What about a test between a Hydraulic roller and Solid roller both with the same exact specs to see what difference is shown? Just a suggestion, love the videos.
That top set was turning 6600 revs, that's a piston speed 4950fps. How long is that going to last? That's NASCAR piston speeds and those engines are sketchy if they cool down even once and they have a lot more cylinder wall to dissipate the heat. The guys that I know that track them suggest driven hard a stock LS7 isn't likely to see 60k miles and certainly not uncommon for them to fail in just 30k.
@@richardholdener1727 I've never heard of that and all found was stuff for ATV and sports craft. If that's what your talking about then even on sport bikes that rev over 10k they keep the piston speeds under 5000 fps, so does F1. Top Fuel Drag car go much higher but those engine don't even see 5000 revolution between rebuilds. The highest used in a a production vehicle that I've found is the Cosworth 6.5 V12 which hits ~5100 fps used in the Valkyrie which is about as mythical as the name. My question is really what is that expected lifespan? For my rotary my builder said about 60-80k. I'm also quite certain it's not going to be 200k plus you would get from a LS3 that's wasn't thrashed daily.
@@GlassTopRX7 but who on earth would build this engine then expect to get 200,000 commuting miles? Minimal servicing, cheap oil, traffic snarls. Really?
It's not piston speed that's the killer, but piston acceleration. If you double the rpm the acceleration down the bore at tdc quadruples, it has to get up to twice the speed in half the time. If you double the stroke, acceleration doubles, it's twice the speed. There was an engine builders article 20 years ago where they built a ZL1 aluminum 510 (4.310 bore) with 4.375 stroke that they spun to 8100rpm. The piston speed on that is pretty mental, like 5900fps. This engine has all top quality components and if you were to daily it, it would.probably be the valve springs that would start to sag first, but I have no doubt it would easily last 100k miles of commuting. The bigger problem you have it's 500 cubes and 800hp and it would be ridiculous thing to daily. Eventually you'll start to burn the ring seal, there aren't too many piston rings that can take NASCAR power levels for years and keep smiling.
Those ls7 have a big throat for that huge cam. Shoulda named this project... deepthroat horsepower
No
Best to call it
Linda Lovelace 💋
Richard, any chance of redoing this test on a stock ci 427 LS7 with updates on the heads? I lot of changes have been made within this market over the years and 99% of the LS7 based engines are going to be 427 ci. Would love to see this done with a 102mm NW TB and MSD intake as well... again being more of the norm.
I agree
I second that.
Also listing the price of each to cross reference cost vs gain. Would be interesting. Is most expensive the best or not?
Richard I'm with you... I believe if you had a serious solid roller the difference would be night and day!
Another 100HP and perhaps another 1000 RPM?
@@dennisrobinson8008 With a good cam and either Mast 305 or BR7 300 heads, you can easily get into four digit power with a large inch LS
268/286 split, 114+6 and .799 lift. Oh, and that is done on hydraulics...
@@AB-80X crazy... thats incredible.
Great video, I would have liked to see you test a set of Frankenstein's LS7 heads.
Me too
How about test 427ci, which is what 95% of people are buying upgraded LS7 heads for?
yep a logical choice would have been a 427 motor to test not a 495 !
And intake set up that fits under the hood of C6Z’s and Z28’s.
@@540chevhell9 He was trying to max the heads out.
Should've been on a LS7
427ci isn't enough to actually test them lol but the results are the same just like if u test a 4.8, the results are the same on a 6.0 just a higher starting point for the numbers, and tq coming earlier rpm. It's not hard to guesstimate 427 numbers
Thanks so much for doing these videos! Would love to see this video done with a stock bottom end ls7 427 and with some other heads like a set of greg good ls7 heads, trickflow genx 260(what I have), prc 280 and so on to see what option for us stock bottom end ls7 guys makes most sense
Can’t believe it took me a year to watch this. Great test glad to see so many LS7 cylinder head options tested back to back. Looking through those numbers it looks like the exhaust ports were the dictator on the best power levels for this combination. Would be awesome to test this with a big solid roller.
I was looking at low lift flows. A good low lift flow makes it act like it has a bigger cam.
Amazing the difference in power numbers from different shops porting styles
Richard, that's the engine for your pickup, just tell everyone that you moded your 5.3.....lol
You can run adapters to fit an ls3 manifold to these heads. Run a factory Ly6 truck rec port manifold and make all the torque, you would really have to know your stuff to spot the manifold and adapters but if you could sneak 500 cubes on e85, there is potentially 700hp with roughly a factory outward appearance.
Nice job showing the different heads, since you weren’t going for max effort but just trying to show the differences in the heads, I think you accomplished that. Would be cool to see a follow up video highlighting different cams. May be cost prohibitive and time prohibitive to have to change valve springs over and over. In any case, good job and keep it up😁
I love the comments from the 427 guys telling you how high to rev the 495. Apples and oranges, like trying to compare the displacement of a 346 or 364 to a 427.
The camshaft used was a medium sized grind for that size engine so definitely not small.
I would have used a 265/279 114lsa.
Also Richard you really need to rev those ls7 heads out to at least 7500rpm as this is where they shine and are in essence a big bore high rpm race head. I have had experience with these in my heavy car and did not like them because at any rpm under 4000rpm they dont have a lot of torque to get the car moving and under the curve power is average at best. But from 6000rpm+ they start coming to life.
A solid roller would also be a great idea.
Using comp cam ls street solids you would need a 272/286 cam.
There is a member on corvette forum who made 800hp with an ls 454, mamo reworked ls7 trickflow heads, Mamo ported MSD, 13:8.1 compression, 264/276 112lsa +3 comp cams steet solid roller.
I still think Richard, you should be the one to settle the trickflow 245 vs AFR 245 head debate which has been going on for years. Most prefer the trickflows because they claim they make more power but from what I have seen it is the AFR that comes out on top.
Get an engine at least 427 cubes.
Make sure everything is the same with the only change being the heads so the test is fair.
I really liked this test too.
Definitely needed a bigger cam. You can see the power level off towards the top. Bigger cam and more rpm would have be cool.
agree on this....and the interesting test on afr vs tfs 245......more real world--
nice test for a 427 ...12.5 to 1....nice solid roller (270-276) with a 950-1000cfm 4150..
or even a pump gas 11 to 1 427 with above roller....LOL
These numbers are pretty big....on hyd roller. makes a real low maint street bruiser, but the stock heads can handle that pretty well. need another 1000 rpm for the better heads to show themselves.
These LS engines run well....but as Ford guy, the windsor isnt too far behind....but you need a dart block and good rotating assembly 700 on a 427 is fairly easy....and thats not a canted valve head. another great test.
there is another great test.....427-460 sbf with higgins-or D3 heads (12.5 to 1 with a decent roller---270-278) and you will find 850hp and streetable.
nice channel! well presented, clear and no BS.
@@harryharry3193 I vote AFR. They have a Helluva power curve, and low lift flow......
We're going to need you to slap a couple turbos on that bad boy, then we wont really care about the cam, right?
This would have been stellar and a lot more work to run each set of heads with a huge solid roller too.
I would love to see something like AJPE heads compared to the regular heads.
Always delivering the goods. Great work as usual. Keep at it, I'll keep watching ! 👌🏻😎👍🏻
Richard, I want to thank you for bringing up the LS7 heads test. That was Awesome!!! I would like to see the same engine size you used to test the ls3 heads. This way we can see the difference between one and the other. Thanks!!!. Keep it up bro! 😎👍
The LS3 ported heads flow enough to support the 468 power level
More great info! I don’t see flow numbers at 0.800 lift, were any of these heads tested there? Also, I was hoping to see what TFS GenX 260s were going to do. As to your questions, this is big block territory and I’d think more lift (like 0.750 or 0.800) would be good. Thanks for the coverage even if this is way out of my budget!
I didn't test at .800 lift because of the small cam we used-but I should have
Love these custom engines. Still hoping to see that big block caddy. :-)
As to the one comment it is definitely big block territory on the intake but the exhaust cfm on big blocks are low to mid 300’s on a good cnc big block head , but absolutely impressive heads and motor .
If you want that kind of flow look at the Dart 10º LS7 heads.. they do that and then some; 450+/320+.
Had to re-watch this now that I'm looking at an RHS build. I'm entirely jealous you got to punch it out to 495 cubes. I wonder if a big dry sump will put in some power by cutting windage. I was thinking of running a bunch of stages, then a tank that hangs off the front of the engine by being tapped into a dirty dingo bracket setup. No more pickup tube. Just some AN lines that go to the tank so it gravity primes. Dump the vapors down the header.
I clicked together some other combinations. One was a 454 that had tough 1.304" pistons. I wonder if the smaller displacement will shift the parameters up enough such that it works better with the intake manifold and makes more power by dumb luck. If not, it's perfect for spray or boost.
yes on dry sump
I sent out my LS7 heads to Advanced Induction a few weeks ago. Was hoping to see AI’s 280cc heads in this video but regardless thanks for the comparison 👍🏻
Watch RPM (race proven Motorsport). A lot of customers get their ls7 heads fixed by AI. You can watch the dyno pulls.
FYI
That's what I have on a C6 Z06. Makes 630 rwhp on pump gas, unported MSD.
Johnny Moran Did you do a full stage 4 kit from RPM? Was looking into that for myself
@@bigbrown2690 I did not use RPM, but they seem like they do nice work. I also used a BTR-4 cam. It's pretty rowdy, doesn't like 6th gear.. I have QTP cutouts, and it's rude!
Rickybobby 03 I’m subscribed to them, I know they flow well and can make great power but it would’ve been great to see how the AI heads perform against others.
Richard you sir are putting in some work great video. That combo would be great with 2x200 shot of gas on the street 1200hp on a 10.5 slick hard to beat
We hit one of these strokers with a dual quad nitrous test
I have a set of the COPO 427 LS7 heads, destined to live underneath a 2.9L Whipple. Everything is better with BOOST! I'm guessing the COPO head is very similar to the CNC GMPP head.
Excellent information. 👍
Hey richard, have you ever tested, between stock vs polished (no ported), on intake or heads
Did the rougher surface, mix air and fuel better for carbureted engine?
I think surface does very little
Richard is right about this. The discussion is years old now but your going to want to have the intake system that flows the most air and a carb that works properly. You can get some fuel puddling issues if the surface finish is too rough and has a pattern that is parallel to the direction of flow. There is turbulence on the port wall that causes a boundary pressure region that causes the fuel to drop out of suspension or deposit. There is basically no such thing as a port that is too smooth. When you get fluid flow in the port making tiny eddies along the walls, the pressure in the area goes up, the fuel condenses and then can't change direction as fast as the air and sticks to the side of the port. Think if you had an oversize valve seat cut without blending it into the port. The air would be flowing along nicely then it would come to the edge of the cut, slow down and crash into the square edge of the valve cut. It's the same thing that happens when the back window of an SUV or the tailgate of a pickup gets dirty. The flow makes a quick 90° turn and the dirt continues strait into the glass because the direction of flow has changed. If you ever notice how dirty the doors of a van body highway trailer get, its for the same reason.
There are some guys that still claim that rough cut or raw burr finish is the best, and usually it's really good if it's a cnc job with tiny feed rates. Both Wilson manifolds and SME fabricate completely billet manifolds with no design limitations. Wilson builds billet intakes for pro outlaw twin dominator big blocks, and even though the ports aren't polished, they are almost mirror smooth right off the cnc.
Hi Richard. I’m looking to use a Dart LS Next block to build a torque monster for my 2015 Sierra to pull my travel trailer. But, there’s not much info around about stock heads heads. I thinking about the 706 heads for torque but will the engine be starving for air? Any input on this?
LS7 block
706 Heads??
4.100” Stroke
9.5:1 pistons
Lunati Voodoo RV cam
Trailblazer SS intake
not really a good choice for that size bore
For that size bore you really need a better head. One of the BR3 or BR7 offerings would be a good choice. Just buy them from someone who can put in a proper durable valve job and set them up for what you are planning on doing. A guy like Eric over at Weingartner Racing seems to really know his BR heads.
Another awesome video, thanks! I'd like to see some LSA motor/head testing!
like to do some lsa blower testing
This is an awesome test Richard. But I wish I could see what these heads did down low below 3000. Im debating putting some After market heads on an otherwise stock LS7 and wanted to see if it would retain close to stock characteristics down low driving wise or if with putting a set of these heads on you lose something down low. I love how the stock LS7 drives with so much torque down low. Don’t wanna lose that. Was just thinking of putting heads on to possibly to remedy the valve issue.
Fantastic videos.... please don’t forget the Chevrolet 2.2 single overhead cam 🙏🏾🙏🏾🙏🏾
What’s weird is that the LPE heads had the highest flow numbers but didn’t make the most power, ? And higher flow should equate to higher hp , ? Why ?
Fyi all factory LS7 heads are cnc ported, its just that the factory versions leave a lot to be desired
I thought that as well. The factory ports are also designed for only 428 cubes and 510hp (without accessories and with headers like Richard tests, they would be closer to 570-590). They also have that mass produced stigma where gm got to where they needed to be and stopped developing the head. For all the production limitations, it might not be worth much, even the best performing head here might only add 10-15hp to a production engine, with the factory camshaft.
It's been a while since I had a set of LS7 heads in my hands, but I'm quite sure it's only the chambers and not the runners that are CNC milled.
Nope they are 100% CNC ported they're just a very rough CNC port all LS7 heads were CNC ported from the factory
Build a short block that will handle 7500+rpm and then test these heads again
The components listed here, K1 makes awesome cranks, can take more rpm than the ring pack. It's the hydraulic lifters that will limit you every time. This is begging for a solid roller, 8000 is about as fast as your gonna want to spin something with a 4.5" crank but this combo would probably make another 100hp with a solid cam and bigger headers.
That mill in this vid will support 7500. You just need a bit more cam. Add the Cam Motion Nitrous LLR cam with .765 lift and 267 duration and you're easily there.
Great Work,,, now if i can only squeeze a set of ls7 heads on a 6.0 gen3 iron block,,,
Notch the bores and have at it. There isn't much point over rec port heads unless your gonna run the cam.
Theres a long standing debate between which is better of ported LS3 vs as-cast LS7.....If I were you I'd stick with ported LS3 so you don't have to deal with valve-cylinder wall clearance.
you can put them on a 6.2
@@rustysausage69 thanks Mac,, looks like I'll stick some 823 casting Rec ports on it,,,
@@timothybayliss6680 True,,, was thinking bout building a grenade engine as i traded a 1st gen sbc 350 for this Lq9 in Great Shape out of a Escalade to stuff in my Vega
Just fired up my TSP 427 last week. PRC 285 heads. Break in then dyno.
let me know how they do-sounds like a good combo
Don't you mean.... "Just fired up TSP 427................head. Then broke the dyno"
@@tomnekuda3818 Its my half shafts I'll likely be breaking (again). Ive got my Novi 1500 spinning at 55k rpm at 7k this time with no restrictor. Should be good for 950 flywheel or so. Managed to touch ring ends in number 7 on my original LS7. Several times at that. Then the piston left decided to leave the rings behind. Displacement on demand right?
Richard, I need to replace engine trans and transfer case on 2013 suburban. I have driven crap out of it. Pulled to heavy trailers. If I buy a GMC or Cadillac SUV with 6.0 or 6.2 how hard is it to install? Do electronics have to be swapped. Or do I drive suburban off cliff? And buy new one. A good copart rig is running in $6k range
not sure about swap on that
What do I think? Holy shitballs! Things have really changed since 1988. Car companies have got enthusiasts, and not bean counters, running their engine development teams.
Thanks, as always you give outstanding tested information. Richard what is the effect of compression on turbo engines? I was always told you want less compression on turbo engines.
compression adds power at 3-4% per point in the sweet range (8-12.0:1), racers use high compression and boost with high octane and good intercooling
@@richardholdener1727 Hi mate, id love to see more on this, the way i see it, compression is like camshaft, if every cam is a turbo cam is every compression turbo compression?
Richard I’m not bullshitting you when I say the set of lsa heads Greg good ported for flowed very similar numbers to the brodix and mast ls7 heads...... I would love a comparison of a set of heads from Greg good , Frankenstein , modern airflow dynamics. P.s I already know the winner
Lots of good stuff out there
Amazing test!!!!
Hey Richard. I just bought a 351Windsor and I'm wondering what cam, carburetor and intake manifold combo would work good with stock hand ported and polished heads. In also going to be running short tube headers. I don't want to just go with a giant cam, but I also don't want to undercam it. Appreciate if you manage to find and reply to this. Maybe even make a video on the Windsor. Thanks!
Your heads will be a big limitation. You didn't mention your application, but amateur ported OEM 351W heads on a healthy shortblock would probably be best with an Edelbrock performer or performer RPM intake (or similar), a 650ish carb (750 will work but too big), and a cam with no more than about 220º @ .050. I'd think *REAL* hard before putting ANY money into stock heads when anything aftermarket aluminum will beat the pants off those stockers, and save almost 80lb on the front of your car.
the Comp XE274HR and dual-plane RPM Air Gap works well and 650 or 750 Brawler carb
Appreciate it!!!
Hey Richard,
Do you have the part number for the SDPC heads you used? Also for the MAST heads? Good test! Thanks!
Richard, how does stroking an LS engine affect the rod /stroke ratio? The 400 CI had a poor ratio of 1:48 creating a lot of side wear on the cylinders.
rod ratio is not really an issue
How about alternative fuel comparisons like CNG and Propane? &E85
He uses race gas or E85. Unless he does more with the compression I dont see any benefit to CNG or Propane...I could be wrong though.
Not sure there's much of e general market for performance CNG and LPG. Might need to find yourself a northern Canadian engine tester for that one.
What about heads from AFR and Trick Flow?
not avail when tested
Hey Richard, we have talked before about my LSX454 in my Pontiac G8. I have 11.5 compression, ported factory LS7 heads with a 275cc intake runner and flow numbers that closely match the TSP head in this test. It looks like this was the same test you ran for your LS book? That book has been such a great help! Anyone reading this should buy it!I have a small cam for this size motor at 239/254 114 .660/.630 on a 1.8 rocker. Through a 6l80e auto it made 540rwhp, 525rwtq on a dynojet literally yesterday. Those numbers are SAE and uncorrected. Shop temp was in the 70s and humidity was high so I'm not sure how that would change things in a STD corrected format, or even SAE correcred. I am getting ready to toss in a bigger cam, and did look at the same cam you ran on this test. Do you think it would pick up an honest 20-30hp at the tires all things being equal? I'm trying to find the limits of this combo and know a bigger cam is a must. I do have a ported MSD intake which I know all the Corvette Z06 guys like, but maybe something with a bit shorter runner (MSD runner is about 9", Holley Hi Ram is about 6" for comparison) would also help this thing out. Have you ran any EFI intakes on an LS7 headed combo?
I did run a a Fast on this
What about AI or AFR. Otherwise awesome video! Have you tested small bore ls7 heads on an ls3?
Hi Richard, it seems (not specifically from this test) that the smallest intake port volume....max flow being equal, will always make more power. Do you find this to be true in general?
Same thing was observed recently with the BBC heads test [both oval and square]. The smallest volume but highest flowing heads gave the best results thru the whole curve.
I like the most flow through the smallest port and valve
For the rpm. These are great numbers. Now i ask...if this combination was in a big block chevy. Lets say a 496ci, 13:1 with a cam of the same lift. Would you top these power numbers? And a similar power curve?
BBC head can flow more than this
I looked back at a early bbc video. Seems thise test were about 100-150 hp less. Except the brodix head had a bunch more power below 5000. With all the videos. Iam seeing smaller more efficient ports create more usable power the big ports. Can you make a video just comparing exhaust comparisons. For instance...the sportman II heads had 200cc intake ports but the exhaust side restrictions hold them back. Same with oe bbc heads.
@@approachingtarget.4503
When you ask that question, you need to factor in which heads you are talking about. Are we talking a set of "bland" as-cast Dart 325 heads, a set of stock Gen VI ported heads, or say a set of Sniper X 375's? The first two flow less than the Mast and less than a BR7 273 and BR7 300 for sure. So in essence that would make less power. Now fit that same engine with a set of AFR 357's or a set of Darin's Sniper X 375's and things change. That said, if you were ever to make 800+ hp from a BBC, even a "small" 496 BBC, why only use .660 lift? If you make a setup like that, there are several things you should do to make it a better combination. Start by having the cam tunnel machined out to accept a 55 mm cam. That way you have some of the lobe geometry advantages of the LS. This also allows you to run more lift which the heads would like, while retaining an equally stable valvetrain compared to a stock sized BBC cam core with less lift.
My point is that as you can see, there are a ton of variables. Put peanut port heads on the BBC and it will never make power while a good set of heads matched to the combination will ALWAYS, and I do mean ALWAYS make more power than the equivalent LS. This because as Richard told you, there are always a BBC head which can make more power than any LS head. At the end of the day the LS is still "just" a small block with what ever limitations that brings into the equation.
Richard I have an lq9 I’m planning on port and polishing a set of heads for it what do you recommend I have a set of 241, 243, 317 and 706 heads I have an isky 598 lift 236 duration and 113 lobe Separation out of all those heads what would be best for high rpm application this engine is going into a drift car
ported 243s work well-take a look at the cath head test video
Richard Holdener do you work at the westech in California?
Hey Richard can you test a dual blow through carb tunnel ram like the Holley high ram vs a single blow through carb super vic
Ever figure out the "fix" for ls7 heads Richard?
Fix?
Hello richard could you do an other guys build on a vw aircooled engine thanks. I've been looking to upgrade my VW with cb performance cnc ported cylinder heads.
I just want to know which LS7 head setup won't fail after fix!!!
any after market head is fine or a repaired stock one
I’d love to feel this thing in a car , 700 plus na power ain’t no joke .
The cam u picked seems to be perfect for a street cruiser , less cam timing easier on parts and fuel milage
Street cruiser? It might be a 495, but that cam with those Mast heads will be pretty raunchy. Street/strip deal for sure. Cruiser? No.
Not an engine man. I do think a larger cam would give a better picture of this engines capability. I would have expected to see something in the 0.725-0.750 range for a na motor of this size and caliber. Duration maybe a few degrees more duration. Yes I know now we may be getting into the roller rocker range. Increased lift would probably require more spring for the valves. I’m sure the folks at T/D or Jessel could help with this question on the rocker arms. All in all a great test. Let’s everyone see the potential of the heads tested. Thank you for the video. You keep making them and I’ll excel at watching them.
You can get lobes that will provide .800 lift on hydraulics. That puny .660 number was a major brainfart. People are making 750 hp with 240 degrees of duration and less lift on416-427 engines. That 495 was completely choked off by that cam. Would have been great with the same duration but lift in the .750-.800 range.
Would a ls7 head work with a lq4 bored to 4.070
Cam:
More lift, 0.750" or more and
Tighter LSA, bring on much better torque with the single plane.
Maybe 10 degree more duration.
IMHO I'm no expert though.
Like you say it's what was bottom of the page back in the day.
Unless you kick the lift well into the 800's, there's little need for more duration here. I'd say with 259, just lift it to .799 with hydraulics. If you run 270'ish duration, you are already into max effort territory so just get all the lift the heads will allow.
Where do you find these big displacement LS?
He mentions in the video the block. To fit the 4.5 stroke crank you need a tall deck ls block. The sleeves in it give you the 4.18 bore or what it had. The limit for a production block is a bit less, guys really won't run more than a 4.25 crank and you can sleeve them out to 4.185. I think that gives you 468 cubes. Any production aluminum block is good for this and there is a bunch of gen4 al 5.3 blocks in crummy suv and things nobody cares about that work when all you want is a block. It's lots of work but the payoff is huge. You don't see to much of it for the street though because the factory blocks are so tough and you can make so much power with boost.
8.1 in motor homes.
2001 - 2006 trucks 2500-3500HD
@@roscoetippetts8619 vortec 8100 in the 3500 trucks is a Gen 7 big block chevy (spread-port head design), not LS. The only similarity between LS and gen 7 BBC is firing order. Otherwise the two don't share a single common bolt
Forged 370 cid, milled LS3 heads with .660 springs, vs 317 vs 243 vs Mast vs TSP, etc., single plane, accufab TB with long tubes... The "affordable" combo. The cam was WAY too small for 495 cubes imho.
Was this a 6.0 block in the video
Just needed a ton more lift. If 820 hp was the goal, this cam was the completely wrong way to go about it. There's no problem in lifting .750" on a hydraulic and duration could have been in the mid to high 24X's and it would have been better overall. With that duration, lift should at least have been 750 if not 800.
The Mast heads biggest advantage looked to be in the exhaust flow. Be interesting to see if that advantage was that large in a 416ci, or 427ci engine, as there would naturally be less exhaust. the SDPC heads look pretty damn good. Are they proprietary castings, or are they reworked GM heads?
I was looking at low lift flows. A good low lift flow makes it act like it has a bigger cam.
How about pushing stock 13b rew engine, I wonder how much power can it handle stock with a big turbo
I wish you could make an in-depth video of the differences between boosting a gm lsx 427 with ls3 heads versus ls7 heads. What the advantages and disadvantage be. Of course for N/A, LS7 heads are the way but i'm curious about boost.
whatever head makes the most power na-will make the most power at any given boost level.
@@richardholdener1727 Thank you, you gave me a piece of mind 🙏
Where are the MBE/Dart 10 degree heads? JK, I know that's a major architecture change but would love to see a set on this size motor. With the 'right' camshaft of course. 😄
this was done before those existed
@@richardholdener1727 Ah.. time stamping. Think they came out around the same time as this video. Looks promising.. those and the Edelbrock "Race" heads. Thanks all the same.. really appreciate what you do here Richard. 🤜
Would have liked to see the TFS GenX in there ... or better yet, the MMS265 version which I am told go over 400 cfm below .6 lift and do it with a port smaller than the as cast LS7.
400 cfm at .600?
Mamo seems like a god of the high ports. I've seen one thread where the claimed numbers were 387 at .600 and 404 at .700. That's a couple years old now and he might have improved his cnc program. There was a time more than ten independent shops all had Mamo top end ls7 as their highest na horsepower for any ls7 engine. He really seems to know what he is doing.
You need to get out more. If you really want to see what can be done when it comes to 12 degree LS7 style heads, you need to get down under and visit CID. Mamo knows his stuff but he is not the best of the best, especially when it comes to LS heads.
As for Mast 265 heads flowing 400 @ .600? No, not now, not ever. I've seen a set that had been properly worked over with good valve jobs, a more efficient short side, and a few other little tricks, and it was about 360 @ .600. Heck even Mast claim 370 @ .600 and those numbers are a bit on the happy side let's just say.
The best small port LS7 style head I have ever seen was a hand ported as-cast BR7 that had been reworked to about 260. It was in the low 370's from .600 to .800 and never got above that, but never dropped off either. I believe it was done by CID in Australia as well. Go and ask Darin Morgan, Tony Mamo and even Horace Mast about CID, and you can be pretty sure that when it comes to LS7 heads, they know that's where it's at.
Reality is this. Tony Mamo has kind of become a household name because of his association with AFR so many know of him, but while he's good at what he does, there are definitely head porters I'd choose before him. Go and see what moves in the wonderful world of custom ported heads and custom program CNC heads, and you'll find that Mamo is not the guy those who really want the absolute best seek out. Again, he's good, very good in fact, but I don't think he's the "God of head porting" some seem to think he is.
Anyhow, go and check out CID, they are the dogs danglies when it comes to LS heads. I have never seen any 12 degree LS head flow as good, not even my BR7 300's which have been ported and had a proper valve job done. And by the way, my BR7's which started life as the 300 CNC heads only just flow 403 @ .600 on a conservative bench.
I'm looking at avg hp/trq, as well as idle vacuum... other than that overall drivability, as it must be driven in traffic... whilst still kicking ass. Maybe odd, but that's what I'm looking for.
Not odd at all, I think we are all searching for the Jekyll and Hyde, but I am becoming convinced that (at least for N/A) what results in idle vacuum impinges on high RPM flow. Sort of like you have to leave something on the table on one end of the spectrum.
You need cubes...
you decided what best suits your needs
Hey rich can you get a 8.1 for heads/cam shootout? Curious with the different head designs if its worth swapping a mark iv for
I think you’ve got too much stroke. Are you running into flame speed issues up at 6500 rpm?
Really? Tell me you are writing that to make yourself look cool, please.
Flame speed... Tell me again what determines flame travel speed and what we use to account for it?
It would have been interesting to put a set of solid roller lifters in for a couple pulls. Just to check for potential hydraulic lifter issues at high rpm.
think there was a typo on the stock ls7 vs GMPP heads the flow numbers where the exact same?
yes typo
I cant wait for my engine to get built. Ive got the rhs tall deck and the brodix 273. So glad you used these and put some concern behind me. You must live at the dyno shop?
I really hope you have a LOT more lift than the puny .660 used here.
"Up next. Whipple 5 litre on a 495 LS7".:D
Question maybe you can do an L18 8.1l (496ci)it can go to 1000ci. One of few Marine rated Motors. Turbo stock internals?
I was figuring maybe the turbo can push right past that restriction in the intake.
I plan to get one of those
I'm pretty sure we all will be waiting in suspense!! I know I will be.
Would be interested to know what RPM’s proprietary CNC heads would have made. Curious how they’d do with the bigger cube bottom end.
Thinking they use Advanced Indiction ported stock Ls7 heads for their combos.
RPM's? So how many minutes do you want to measure the revolutions over? It's one minute, not several. Revolutions Per Minute, Revolutions are plural, not minutes.
Are you starting with a 6.0 block .030 over
THIS WAS A MUCH LARGER BORE rhs BLOCK
Everyone I've talk to has told me to run the black label heads on my Z06 but I'm torn between those and the dart pro heads
Richard Tisdale black label
Forget that stuff. Contact CID. Best LS7 heads on the planet.
For that set up i would do a 266 @0.050 279 @.050 ex .777 .750 lift 112lsa plus 4* tight lash solid roller
How much further would that have stretched the power out? The cam he mentioned had 259@.05" intake, .660" lift. 115 lsa
@@dennisrobinson8008 It would probably not have moved it all that far up. But what it would have done, was to massively increase power over the entire curve. With a .660 cam, those heads weren't even starting to breathe. You need to get into the 750-775 lift area to even see a real advantage of the head's .700 lift flow capabilities. If one goes into a solid roller, low lash or what ever, might as well run .850" of lift. .750-775" lift is easily done on hydraulics.
That said, if the intake was 266 as suggested, I'd probably run 282 or 284 on the exhaust seeing we are dealing with LS7 style heads.
Did you run a head to intake adapter? Do you think it hurt performance any?Would like to do a ls7 to ls3 intake adapter
FOR THE TALL DECK? YES-i DON'T THINK IT HURTS POWER
Surely Comp can grind a custom cam for you now. You have done more than enough for them. These catalog cams kill me and I know it was holding this combo back, just not how much.
I'm guessing 50 - 100 lb/ft and 100 hp
@@indyrock8148 that's probably pretty close on power, there are guys making really close to or over 900 at the crank with huge solid rollers. It seems strange to me to have an aftermarket engine from top to bottom and still keep it under 7000rpm with a hydraulic camshaft. A couple hardcore guys are really close to 1000hp NA, but their setup is completely focused on runs 8 seconds at a time an 1320 feet. You could daily this if you eat nails for breakfast and have e85 local.
Anyone can order a custom cam from Comp. Just look in the master lobe catalogue and select the lobes you want with the LSA, ICL etc. They offer hydraulic LS lobes that goes to .800 lift these days.
I would of liked to see this test with a Dual plane intake , low rise intake . Big numbers up top everyone enjoys seeing including me but u would love to see some down low stump pulling grunt . Start the pull at 1,500 - 2,000 rpm and let it eat
If you build something to do that, nothing here is what you want other than the displacement. Nobody, and I do mean nobody would ever run full throttle at those rpm, ever.
If you build a truck engine for hauling stuff, you are building something different.
As long as you have more than one gear, and especially if you have a torque converter, there's zero reason to perform that test. As soon as you put your foot in it, it will rev up to at least 3000 rpm.
I reckon a solid with 270/280@050. 720 plus lift. These heads should make power to 8000 your running out of lifter at 6500,these heads are still yawning at that. I’m running a 260@050 hyd with a 1.7 rocker and tighten up the lobe centre like a 110/112. 115 is almost a blower grind, but I am an amateur!
Why lift at .720 with a solid when hydraulics go to .800?
Have you ever built a high horsepower big cube LS7? I ask because your numbers seems to be those of someone who has a slight idea about what would make power in a 509 BBC 25 years ago, but not really what is possible with a big inch LS.
Those cam specs for example, makes zero sense with any of these heads or the rest of that package. And if you wanted to take the duration all the way to 270, lift it to .850 and give it 288-290 on the exhaust with 113-114+4 on the LSA. Those Mast and BR7 heads need lift, lots of it.
It might be interesting todo 6.4 Hemi/Apache head, ThiTeck Heads, or one of those aussie DOHC straight 6 or a Rover SOHC engine....Id also be interested in seeing what ceramic coating the pistons/combustion chamber does on some old stock iron heads (as far as overall engine temp and hp). It might also be interesting to see a chassis dyno comparison with a Carbon Fiber Wheels and drive shaft vrs stock aluminum Rims/Driveshaft. Probably have todo a mustang
I have tested carbon fiber driveshafts and wheels and flywheels
Do u need to put new piston and rods to get 700 hp on a 5.3 or just cam and springs
If N/A, absolutely.
.660 lift and 259 intake duration on the cam. Probably lost 5-10% due to deflection, so we are achieving up the .600" lift numbers on the heads, maybe a little bit more. Very interesting you were able to get 800+ HP in this case.
.060 deflection? no
@@richardholdener1727 There is certainly some measurable deflection.
@@richardholdener1727 Weingartner was a fan of more lift to overcome the deflection. The stiffer the spring and greater the rocker ratio the more deflection. th-cam.com/video/3SMMr4GQB8k/w-d-xo.html
@@dennisrobinson8008 Lol. Have you ever measured deflection on an LS? For starters, an LS uses a 55 mm core. That alone has a lot to say. 259 degrees of duration @ .660 lift? That's nothing, and I do mean nothing. Unless he uses spaghetti for pushrods and some kind of shitty Chinese rockers, there's little deflection here. Maybe .005"-.008". I helped a buddy who had some issues with small block, and it turned out to be a combination of crappy pushrods and not running a stud girdle. It was lifting in the .740 range with a solid roller cam, and he had chosen some cheap thin walled pushrods because he though light pushrods would be a great idea. With the lack of proper pushrods, not running a stud girdle, spring pressure for a healthy solid roller in the .260 duration range etc. we measured 0.023" of deflection which is a lot by the way. Installed proper pushrods and a shaft rocker kit. Deflection was almost gone.
If anything, the .600" number is relevant for an entirely different reason, and that is because a cam with a .660 lift, will only lift that valve @ .660" for a split second as it goes over the nose of the lobe. This means that ,650" flow numbers are pretty much pointless in this case. Everything here happens from .620" ish and down, if not .600" depending on lobe geometry.
I think something in the 427-440 range with a big solid roller, twin 98 turbos and around 60lbs of boost.
60 psi?
Why not, run it on alcohol with a billet block, crank and aluminum rods. Gotta make that 4k hp somehow.
Just throw some nitro methane at it and run the numbers on the dyno to 9k rpm🌋
@@HorsepowerHeadquarters454 I would really like to see a nitro test. I don't think any dyno will reliably hold that much power. If you used a 5.3 with a blower cam and tuned it, then fed it 90% just to see what the difference in power is, it would be a really interesting. Running a cheap engine that your going to beat the bearings out of can still show some awesome results.
@@timothybayliss6680 that high of % it wouldnt last 1 pull. Youd be hard to get enough fuel in it though. Having run a mechanical injected bbc then added some nitro the fuel consumption goes through the roof and most people don't have enough fuel pump(s)
Maybe the bore is too small for the intake valve causing shrouding.
Ya needs more cam
Right on
The issue is what cam could he have run circa 2011 when he did the test. Not what's available now.
It seemed strange to me to run as much stuff as you could, but keep the hydraulic camshaft. 13.5 compression will keep this off the street unless you have e85 but how much was spent on this combo its screaming for more camshaft. The guys that run these combos hard will run solids to 850 lift and spin the engine fast enough to cause local disturbances to the weather. This was a really good test, it showed some discrepancies between parts like any test should, but it's almost impossible for me to believe that anyone running a completely aftermarket engine (block, rotating, heads) will still be running a hydraulic camshaft when a solid could add so much.
Nice one.
Can you post the chart with port volumes, valve sizes, chamber volumes, etc?
I should have
Any news on the availability of your ls camshafts Mr. Holdener?
be a while
@@richardholdener1727 I need to order a couple ls cams, and I'd rather support YOU, than anyone else. Love ya buddy, You do some great research.
would a z06 ls7 fit on my 04 silverado 6.0?
the intake won't fit-nor would you want it-the entire engine will fit
I know you have done a gen 6 BBC but any chance I could get some gen 5 peanut port love? See what the old girl will do with a cam! Intake! Headers and More!
we used peanut ports as the base heads in the BBC head shoot out video-check it out
@@richardholdener1727 Ah I missed that dang it.
LS7 stock and GMPP were identical. That seems incorrect. Also, test DART, PRO1 and Frankenstein.
Richard, you ever get that 5 bar map sensor??
no 5 bar
@@richardholdener1727 just ordered a Holley 5 bar. Headed your way to the shop at Westech. Thanks for the great vids and I hope to see this sensor maxed out at some point... haha!
It's insane what those dirt cheap speedmaster heads did on there....
What should I do? I want 777 hp or tourque from a chevy engine. Can be a bigblock or ls... Any advice? I really want a 777&777 from a engine in my small eu box... And yes I am massively into numerology...
You can do it with either one. It's the money you are working with that is the factor. Even now in the days of boost in every motor the old saying of "no replacement for displacement" is still very true. If anyone disagrees look at all the serious street car guys. A 540 or 632 is considered "small" lol
Build an 800 HP engine and then restrict flow back to 777... or tell the dyno operator to adjust the correction factor until it computed peak is 777 on the nose and print the chart. (No two dynos are the same so peak HP numbers are sort of subjective).
Build any motor with boost like one of those junkyard 6.0 that Richard likes. Add boost and a controller and so long as you can get it to handle the 777 torque you can let it bleed off the excess boost on the high end so it only makes 777hp.
a mild 632 BBC will do those numbers
@@opieg7333 Lolz. I did cup car engine testing with GM back in the late 2000s. We had amazing test cells that were super premium with all the latest fancy pants equipment. We calibrated the dynos every 6 months, which included calibrating the load cell with dead weight, and then installing our "gold standard" stock 4.8L to verify everything was reading normally. Then Hendrick or BNR or RCR would bring an engine for us to test and when it showed 79x on our dyno, they'd scream and yell and tell us our dyno was wrong - that back home in North Carolina, their Superflow read 83x hp. There was no arguing with them, so I'd just calculate the multiplier needed to hit whatever number they wanted to see, and display HP/TQ that'd been multiplied by my offset. Always made me shake my head, considering we had a $10M test cell with all the best shit, and here I am "correcting" the numbers so they'd say what the customer wanted to see...
Since torque really isn't an issue here, I wonder what individual throttle bodies would do on one of these, or even a stock 7.0 liter engine but with the rest of the mods
Torque also means something in relation to drivability. A Harrop intake would be cool, but not sure there's a lot to gain other than looks. That Mast intake is really, really good.
@@AB-80X my point about torque is that the LS7 already makes mountains of it. When Harrop 1st came out with their ITB setup they put one on an LS7 then returned the engine bc of the intake and picked up 50 who on the top end. Now, that being said of course part of the gain was from just being tuned but it HAD to be returned cof the ITBs. Most of the gain was from the ability to breath better at high rpm. Not sure what it did to peak torque or the curve but with an engine this big in a street car it should be that big of a deal
What about a test between a Hydraulic roller and Solid roller both with the same exact specs to see what difference is shown? Just a suggestion, love the videos.
that has been done-but the solid loses due to lash
@@richardholdener1727 Then why do we use them?
@@tenorhowlermonkey3454 valvetrain stability
@@richardholdener1727 Actually on Engine Master the Solid won.
That top set was turning 6600 revs, that's a piston speed 4950fps. How long is that going to last? That's NASCAR piston speeds and those engines are sketchy if they cool down even once and they have a lot more cylinder wall to dissipate the heat.
The guys that I know that track them suggest driven hard a stock LS7 isn't likely to see 60k miles and certainly not uncommon for them to fail in just 30k.
try calculating the piston speed on mountain motors-5000 fps is not a problem
@@richardholdener1727 I've never heard of that and all found was stuff for ATV and sports craft. If that's what your talking about then even on sport bikes that rev over 10k they keep the piston speeds under 5000 fps, so does F1. Top Fuel Drag car go much higher but those engine don't even see 5000 revolution between rebuilds.
The highest used in a a production vehicle that I've found is the Cosworth 6.5 V12 which hits ~5100 fps used in the Valkyrie which is about as mythical as the name.
My question is really what is that expected lifespan? For my rotary my builder said about 60-80k. I'm also quite certain it's not going to be 200k plus you would get from a LS3 that's wasn't thrashed daily.
@@GlassTopRX7 but who on earth would build this engine then expect to get 200,000 commuting miles? Minimal servicing, cheap oil, traffic snarls.
Really?
It's not piston speed that's the killer, but piston acceleration. If you double the rpm the acceleration down the bore at tdc quadruples, it has to get up to twice the speed in half the time. If you double the stroke, acceleration doubles, it's twice the speed. There was an engine builders article 20 years ago where they built a ZL1 aluminum 510 (4.310 bore) with 4.375 stroke that they spun to 8100rpm. The piston speed on that is pretty mental, like 5900fps. This engine has all top quality components and if you were to daily it, it would.probably be the valve springs that would start to sag first, but I have no doubt it would easily last 100k miles of commuting. The bigger problem you have it's 500 cubes and 800hp and it would be ridiculous thing to daily. Eventually you'll start to burn the ring seal, there aren't too many piston rings that can take NASCAR power levels for years and keep smiling.