PORT RECOVERY: AN INFERIOR HEAD PRODUCING EQUAL OR MORE POWER?
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- เผยแพร่เมื่อ 14 ต.ค. 2024
- No one really talks about it and even fewer can adequately describe why an inferior flowing cylinder head made more power. An explanation why a flowbench cannot duplicate port "airflow column stacking" and the additional flow it delivers when combined with an effective exhaust port!
Please "SUBSCRIBE" to BEN ALAMEDA RACING so I may continue to produce more in depth engine dynamics without the fancy math and just plain straight forward explanation that many will be able to follow.
Obtw, I get numerous requests for technical advice and if interested, tex me @ 626 203 2712. Half hour to 1 hour+ rates are available. Most calls go over as posted and it is ok. US Pacific time zone.
You should start some kind of live performance class or something. Like once or twice a month. Have all viewers that wish to attend sign up pay a set fee of some sort. Maybe make it to where we all can type questions as the class/video is going. We can all bounce ideas off each other, share what we have. Even if it was in person. I live in Florida I'd fly to attend. Not a lot of people today would help other's. Most TH-cam people are just doing it for the money. I believe you do this from your heart. Thank you
Kyle, thanks for the kind words and appreciate your comments. I will try to see if I can set up what you suggest and perhaps it will be interesting! I have gone overseas Colleges to help others less fortunate than we are and they appreciate it big time. I feel my words can help others understand the complex dynamics of racing engines and overseas students are just as eager. Thank you again and keep in touch. Ben.
Hi Ben. This was incredible! Thank you for taking your time to share some of your knowledge. You explained this topic so well. I would have never learned about this if it wasn’t for this video. If I could kindly request a future topic. Header design, diameter relative to exhaust port and valve, length, type of racing. Thank you
M E, thanks for your kind words and appreciate it a lot sir. I will consider your excellent suggestion and have ideas how to go about them. I dealt with hedder design, exhaust ports and systems as a whole when I gave a presentation to the graduating Engineering Students of MIT in Asia several years ago at the invitation of their instructor-staff. As well as having discussions with several Engineering students from a CA University. They were well educated just needed some practical tips and approaches to verify most of their college instructions that they have learned, like designing systems using CFD's and other computerized systems. Unfortunately many of them are taught to not think outside the box and that is where limitations take a hold and innovation ends and it just becomes a monkey see monkey do process when they finally get to work in the real world.
Great video, great information! This kind of info is what most social media experts and backyard guys are lacking in! Just had a debate on a FB group for SBF’s where they strictly ranked heads on intake cfm and I explained that steady state flow wasn’t everything and that pressure transient dynamic flow was more important! I got no response because they don’t understand the physics therefore it doesn’t exist. I have posted your video links to these groups to steer traffic to your videos and help educate some people.....Thanks for your time and all you do in sharing your valuable knowledge!
Thank you sir for clarifying my video and explaining other dynamics involve in the combustion process. Countless others always use "flow numbers" as potential and that is not really the real world shown by flow bench technology! Keep in touch and appreciate your support.
Sounds like some good engineering for a new flow bench design could come up with a flow bench that can open and close the valves to simulate cam timing.
Today we have the technology to actuate valves at racing speeds but the effects of exhaust pulling on the intake @ overlap will be a challenge to replicate! Herein I feel where again the limitations of simulation will show up.
It is a joy to listen to you explain the complex systems involved in an ICE. 50 years ago I had always heard talk about the BBC (Big Block Chrysler, the other BBC) having high velocity intake ports vs the BBC (Big Block Chevy...lol) and other very high flowing heads, relative to their peers in the same era. Of course then I would ask how the high flowing Hemi head figured into that high velocity design...
X, thanks for your comment and appreciate it much sir! I feel the HEMI is in a league by itself and that includes the Boss 9 heads as part of the mass flowing variety. I feel we cannot really claim them as high velocity because they are so huge and that direct mirror positiion of the exhaust valves, gives reversion a big say on its "inability on the streets" and short of all out racing. I feel the BBC/BBF got a leg up on the HEMIs on the streets if they are limited to street compression ratios. Unlimited compression and intake manifolds/CID with dual dominators then they surely will dominate! lol
With that said I will race them for half a block with my BBC/BBF and will let off because I know what will happen to me. :)
@@benalamedaracing2765 I can only imagine some of the things you've done on the flow bench and how interesting it is to an inquisitive mind. I share that trait.
In the 70's there was a saying, "Gears or cubic inches"
With my friends an I we had gone one step further, we ran both! If you didn't have at least 4.88's your weren't going to be door to door with us for much more than part of first gear. lol That was one of the things about the Hemi was the rpm's it could reach when coupled with a stiff gear.
Thank you for putting this information out here for everyone to benefit from. Very cool Been, Bravo sir.
@@topenddean, thanks for your comments and appreciate the feedback specially from individuals like you that have seen it and done it! There is no other way to explain it but thru experience where we both gain wisdom and knowledge. Both excellent attributes!
Thank you for sharing your knowledge. Totally out of the box.
Absolutely love gearhead videos worth watching. Great tech!
Thanks Rich! I had to highlight other aspects of power potential and not just saying it flows this much and should make more power!
@@benalamedaracing2765 I appreciate all of your tech videos, I learn different things from each I've watched. Thank you!
I like how this video illustrates the importance of matching the ports to a particular configuration, and cam timing, to maximize cylinder filling with minimal waste getting sucked out the exhaust during overlap.
Often people think "more flow more flow more flow".... Versus this video showing how "smaller" exhaust ports (ratio) can be beneficial for a particular build.
I also liked how you explained having a recessed exhaust valve helps fill the cylinder versus pulling the intake charge straight out of the intake valve and into the exhaust port. Great stuff!
Ben we need more guy's like you flow bench and flow numbers are over rated, I am doing a pair of dove heads right now there is nothing good about these heads but the e7s 460 later model heads have raised ports I say even though people say the ports are to small and you can't get enough exhaust valve into the chamber they think that the dove head is a better head due to flow numbers I say when I'm done porting the e7 heads their going to knock the fire out of the dove heads even if they flow less then the dove heads do , my son sent me this video of you and I'm glad he did, I did subscribe and I think you do a great job Thank you for taking the time to share your knowledge with people👍👍
Terry, as you found out it is not all about flow but something more! Keep in touch and let me know how your project produces power and that would clarify what we are thinking about!
Thanks.
@@benalamedaracing2765 Thank you Ben Im going to be doing a 460 segment using the dove heads even though they have very low performance capability and unless you heavily modify them by raising the ports on the intake side and exhaust side, Id love to have you here to share your opinion because people just don't get it about a raised port. I really like what you do especially matching the combustion chamber to the piston design I see exactly why your motors make power and I'm looking forward to more video's from you 👍
@@terrygrover6440, I ran a early 70's 429 casting and installed 2.24 intake and 1.75 exhausts. It had lots of power and ran in the high 12's with a mild Isky hydraulic lifters! It was my brothers and my street car and did all these with 3.55s and stock torque converter ran high thirteens in a Torino 1970 body. Switching to a 460 crank woke it up big time and the rpm capability did not lose any whatsoever.
Thanks for all your input.
Thanks Thomas.
Nice video Ben!!!!!!
Great video l love your knowledge of it really makes a lot of sense something you weren't really think about
Thanks for the comment Jimmy!
I learned something. Thank you. I feel like a caveman building a rocket. 95 351w Ford. World sr Roush heads. Kb dome pistons and TFS stage 4 roller cam. For my 60 Falcon with c4 and m2 front. I need 1.75" headers that will fit the 1.3x1.2 exhaust ports. 351 in a Fox would work but I cant find them. This lesson drives home how important exhaust scavenging is. Thanks.
Great info Sinai
Ben,you know I have been following and listening to everything you put out. I'm always wanting to push the extreme limits on cylinder heads I get given to me. (Mainly cast iron factory small block Ford head's) I'm currently working on a E7TE Ford 302 cylinder heads😭😭😭. I plan on putting 1.94" intake valve's and 1.58" LT1 exhaust valve's or 1.60" exhaust valve's in it. I will be deshrouding the combustion chamber, the valve bowls but, I'm considering raising the exhaust port up far as I can go safely and then fill in the floor until I get the velocities I want. What is your assignment on that? By the way, another awesome video explaining things.
Gary, thanks for following my posts and appreciate it much. Anyway your plans seems the right way to go about it and would just use the 1.6 exhaust valves and no need for the Lt1 valves. Raising the exhaust and widening using the Felpro 1415 or max out to the 1487 and use 1 3/4 primary pipes at the minimum! One thing that really worked for me back then was when I pushed in aluminum or cast iron tubes to be grinded flush on the pushrod bend of the intake ports. Really works big time and needs an offset intake rocker arm to clear the new re-drilled pushrod holes in the heads made possible by the tubes! By the time you did this the intake ports is straight without the constriction of the pushrod bump on the intake ports!
It really wakes up the engine when you do this.
thank you ben, your videos are the best
Thanks for your support Mike and pls. spread my channel.
You said that you go overseas,im guessing the Philippines, i also try & help as many people there as i can,1 student just finished his nursing studies at Adamson University in manilla,the people are So poor but are So eager to learn,i hope to retire in tagayta soon,i love the Philippino culture,
You have a good heart of kindness Tony and agree with you many of them with the hard life still manage to smile and are very friendly people. I was born there and grew up here in the USA but I never forgot place closest to my heart!
Yes the Phillipines people are SO SO genuine,I'm hoping to open a small trade school there in nigsoogboo batangas,,I can help young men to better they're lives by teaching them a small course in plumbing/ electrical/ carpentry/ and of course some mechanics,the old jeepnees are still very simple to work on ,where was your homeplace,???
Keep it up mang ben!
K, thanks for your support and appreciate the feedback always. Salamat!
Port velocity with the right timing Events thats the magic with a lot of other little things for NA
Indeed and that is part of the struggle to make good power!
Excellent video! I’ve been learning a lot lately about Hemholtz resonance, reflected waves and how intake runner length changes these values. Off topic but I saw a testimonial video you did for IC Green oil additive. Does it really work and are they still in business? I see it currently for sale on Amazon but their website doesn’t seem to be around.
I was involved in racing cylinder head and intake manifold work for about 20 years in NASCAR. When I was in community college I wrote a paper on the tuning peaks of a Cup engine Ford vs Chevrolet. Showed why unequal (Ford) made a broader torque band than a Chevrolet (more equal). Learn a ton from Dynomation simulation program. Thanks Curtis!
@@jimmyjimmy5398, agree with you on your thoughts and may I add, the fact that the Fords have same port approaches is great and the outside ports are actually longer compared to the center 4. However, it is not the same when running a sheetmetal with dual carbs then all approaches are more straightforward equal!
we appreciate the your time i wish i lived next door do you have any books
I was a contributor in a book by HP authored by Isaac Martin called if I remember correctly Ford Windsor Engines. There are many more out there and I feel that book is already outdated. Some still applies but they have not contacted me with updates to a newer version.
Is their a way that can be explained on how to tell if the port is being stacked with air and recovering to the best of it's ability. Is that something that can be determined in the assessment of porting and flowed, or is that more of a by the seat of your pants feel like you were talking about in the sluggishness on the shift. Great information by the way, love the way you break things down
Paul, if a given cylinder heads performs impressively against a much better flowing piece then it is very much an indication of a fast recovering cylinder heads all else being equal! Maybe someday somebody out there will make some kind of measuring device with an actuator that would shut the valve off and measure the stacking ability of any given port! That would answer many questions on the dynamics of flow and port recovery.
@@benalamedaracing2765 It may actually be feasible now days to test the Port Recovery Efficiency of a given port design with the advent of electrically activated valve trains. Theoretically you no longer need to run the engine, the head can be mounted to a flow bench with the valves in place and the actuators fully functioning to what ever rpm desired.
@@topenddean, there are flowbenches out there that are capable pulling in 65" and with electronic activation of the valves we can probably get close to measuring port stacking or recovery. I can just see my electric bill at the end of the month with a machine like these! lol . Wifey already complains when I am on that thing days at a time. I just about wore out my bench when I did an R&D for a 24 Hours of Daytona Mercedes team and got to spend countless hours to find something which is not easy by any means.
Obtw, it would be hard to mimick the pulling power of exhaust overlap on the intake port!
Maybe some day because the exhaust is almost or is at supersonic speeds when it exits so I would be scared if I am anywhere on that machine.
Some day, test your engine on the stand and close both valves. Introduce about 130psi on the spark plug hole and gently tap the exhaust valve tip and observe what you will hear and see! It is quiet revealing.
Idk but I think this may have been meant for Juhanas question?
Hi Ben, have you ever tried to get flow numbers for valve overlap on a flow bench? Both valves open at low lift and suction from the exhaust port with a "piston"/block off plate just below the combustion chamber. Not sure if it is possible to do or even feasible. Just curious.
I am sure there might be others that perhaps tried it but to me at this point in time is an impossibility! We have to produce near "sonic" flow speeds to mimicked the speed of the exhaust gases to yank the intake column in to the chambers. How we do that would probably require a small turbine engine propelling the gases to actual exhaust like speeds so that is a big problem.
thanks for lesson!
Awesome and informative videos Sir. Now im thinking the exhaust flow play a part in how strong the signal or low pressure could be. Higher exhaust port velocity may restric the flow, but gives wider tuning window/better for cylinder with less overlapflow, or slower intake port velocity?
Just thinking after watching your video before going to sleep. Thanks for sharing,
-juhana
Indeed if the exhaust port/flow is impressive less overlap can be used on the engine! Few people really appreciate the part exhaust + overlap has a major effect on intake port capability! Hard to duplicate in a flow bench because these signal are very strong and hard to replicate on any flow bench to basically test overlap performance in the equation.
Most ports have high velocity and low velocity areas, i think the chevy LS heads do so well is, the ports have high velocity through out the whole ports ?
LS heads are impressive for street running and sometimes for all out racing.
Hello Ben. I greatly appreciate the videos. So, one can say the exhaust system can play a large role in how the signal relation is between the intake and exhaust ports as well? Thank You
On one of my videos I spoke of the intense pull of the exhaust on the intake ports basically making the poor flowing intake perform just as good a good flowing heads! Signal relation between these two ports are not considered when evaluating a port on a flow bench specially in the case of the intake port!
lol....Ben, all my cylinder heads are inferior...but comparing an iron GT40 with a Cleveland 2v, I like the ports and bowls of the windsors; but the canted valves and valve size of the 2v looks like they would give the better yank during overlap. My home made flow bench is voting for the 2v's. If you were building a 302, and you only had those two heads, and ease of fitment and assembly were not going to sway your decision, what would you vote for? One has 1.72 rockers, one has 1.6. It might only get a GT roller cam...both would get 10:1...and will go in a street car. Is there a clear winner? And if the cid was 351+ would that tilt everything to the 2v?
Are you talking about the Aussie 2V's? If it is then there is no comparison you would have a superior cylinder heads that is hard to beat! If you can flow test and get the actual numbers on your head flow then making a custom cam will benefit you to target that exact cylinder matching the cams to it!
Thanks!
Thanks for your video, got a question on turbo application, would the exhaust valve still remain at 53-55%, or go to 75%.
It is on methanol with 50 lbs boost on intake and 88 lbs on exhaust.
Also what would be a good cross-sectional area of intake and exhaust port as compared to valve size (or etc...), thank you for your time.
What kind of engine do you have?
@@benalamedaracing2765 it is Rolls-Royce Griffon v12, it is a 4 valve head with bad ports.
2239ci 6in piston x 6.6 stroke
6:1 compression
2.08 intake valve
Thinking about designing a new head, canted valves, 2.3" intakes, higher ports (30-35 deg),
@@GriffonGrowl 4 valve heads and can you send me a picture of this @ my Fb under Ben Alameda Racing? There should be enough valve there vs. a canted 2 valve arrangement. Interesting to say the least!
@@benalamedaracing2765 I was thinking about doing a 30 deg valve on the intake valves, since max rpm is 4k...
If i do a new head it will be 4 valve with approx 20 deg angle.
I sent some pics to messenger, under Zuch Fucherberg.
Hi Ben how can I get ahold you. Have some questions would like your input . Thanks. John.
Pm me your phone # @ my Facebook Ben Alameda.
👍
So say you have an option of 2 heads that are the same port volume. Would you prefer the one with the highest velocity or the one with the higher cfm?
Darin Morgan: velocity velocity velocity
Says it all....
Well known engine builders know that the most flow you get with the smallest diameter possible will give us the power we seek! Therefore small ports have velocity the reverse of big ports and it is very important to be aware of this scenario.
Can the piston pull in AFMixter back in the cylinder from the exhaust potr in the overlap period, when the piston starts go down?
During overlaps and depends on cam timing there is a possibility of reversion back into the chambers from the exhaust specially during or at low-mid rpms!
Usually the backwave from the exhaust will happen at this ranges and can come back regardless of the pistons position... Ex. velocity cannot extend downstream enough to prevent this from happening but at high rpms there is less possibilities except if the exhaust is plugged up and now it starts backing up! Hope this is clearer.
Camshaft overlap vs negative overlap depending on how your head flows ?
Yes and having too much overlap can drastically reduce your dynamic compression and reversion can also be an issue coming back to the chambers. A little bit helps to repack back some of the charge that got past the exhaust valve and in this scenario it helps..
Does this apply equally to na and boosted engines or more towards na?
Port recovery or recharging (stacking) still applies even with boosted combinations. It is a very complex scenario and many of the same issues still apply even with boost! Remember the port jamming or stacking when the intake valves are close is what makes boost! Not all goes in and this leftover pressure is what we see as boost and all pressures upstream of the valve is actually a reservoir of boosted intake column pressure and sometimes the "slightly longer" the port the better, but within reasonable limits...
Its port velocity and port density .
Yes both contribute greatly to port recovery. Without one of them we have nothing!
So on a 6.0 Ls does the ls3 head being a raised runner design do this as good as a cathedral?
Chad, more likely than not the cathedral will recover quicker but the high ports will also function just as good if the Rpms gets real high and the port flow speed will be very effective at this range to pack the ports or recharge them for the next intake event! If @ slower speeds if will be lacking compared to the cathedral with a lot of swirl and recovery capability!
@@benalamedaracing2765 7000 rpm limit. A good cathedral may work better on a 6.0
@@CLEEPER1, you are more likely correct!
🔥🔥🔥
Thanks Gin!
You are showing an ls port to a small block port. Correct.
I will tell you why.
A guy told me once, "Change one thing", "Change a hundred things" and he was not far from the truth.
55%,how can an exhaust valve diameter b that small Ben? 55% of a 2.2 would b 1.2
What kind of heads are you referring to?
Or r ya refering to speed or volume?
They are related in the sense a smaller volume recovers quickly vs, a large port! Too much port slows down port speed or velocity therefore you have to find the happy medium.
I don't think there is a time when a person could Stop thinking and considering what goes on in the ports and chamber of a running engine.
Agree David and it is better when we are more informed and aware.
… what happened?!! 😀
Angle
Thanks for supporting my channel!