BIG Power from Small Block Engines! | Engine Masters | MotorTrend
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- เผยแพร่เมื่อ 14 ก.ค. 2023
- Ford? Chevy? Doesn't matter. We love our small block engines on Engine Masters. Here are some tests we ran to get big power out of our Windsors and our Chevys.
#motortrend #enginemasters #smallblock
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What other tests would you like to see?
why bother, we wont see them here for at least 6 years!
methanol.
Using an engine with knock sensors (preferably boosted) Show the octane limitations, or power limits for different fuels, (turbo Coyote with built lower end)??
Are you going to test the Trick flow single plane on the 410 c.i. ? Raise the compression to 10 or 10.5:1 maybe but keep the flat top pistons with relief custom cut to just enough. Use the tapered spacer. Test your primary lengths. Keep the same schneider solid roller 238* cam. Put some nascar tri Y's on there. Enjoy your 550 hp and torque daily street car.
Seeing the before and after of that cheap Chinese intake being ported and smoothed out would be interesting. I bet it would make a decent difference.
I might be the odd man out but if it's made in China I don't care if it adds 20hp, I ain't buying it.
Don't buy generic drugs either then
@@jimkrogh2549 if saving $0.25 on your bottle of blood pressure pills is worth the risk of something like arsenic poisoning to you then enjoy
@@jimkrogh2549drugs are different. It might be a life or death situation 😆
Where’s your phone made?
Your just close minded my guy.
In 1993 I built a 30 over 302 Windsor with shot peened OEM conrods that where honed for a floating small end . Keith black Hyperuetectic pistons , Windsor Jnr cyl heads , victor jnr intake 750 Hp Holley , 10 .5 comp Iskenderian 292 mega flat tappet hydraulic cam stud girdle bottom end , a machined and modified CLEVELAND HEI dissy to suit , this made 365HP ON The wheels through a C4 auto 9 inch diff combo . In conclusion to all this what I'm saying is that the little 302 which was around 306cubes made around 440hp at the crank . They are a fantastic little powerhouse on pump fuel 31 years ago .
how did you modify the dizzy to fit the lower deck Windsor?
Thanks guys I really enjoy watching your stuff keep it up😊
GREAT VIDEO DAVID!!!! GREAT ENGINE BUILD!!! THANKS FOR SHARING!!!! I LEARNED SO MUCH!!!!
I didn't know those old windsor blocks could hit that much HP. Neat!
its a dart block
@@mikec9112 I was wondering exactly how the 80s 5.0 compared. Thanks for the info!
@@mikec9112 A stock 351 block can take far more than that. Never have hurt one in 25 years of running Windsor strokers on nitrous or with boost with far more than 650 hp.
@@mikec9112I always thought the Cleveland’s were rated for more?
@@NAPAuniversalJoints the 363 was for the intake setup. the first one for header collectors and carb spacers was an OEM block
Back in the day, everyone had their own little tricks to get the last pony out of the car. Some of my Dad’s friends ran dirt track. This was back when almost every neighborhood had their own dirt track. These guys had a way to optimize their exhaust by running collector extensions like you guys did first off. But these guys had a unique way of finding the correct length. They would paint the pipe with white paint and run the car around the track a few laps. When they came back in there would be an area where the extension was burned. That was where they cut the extension off. Don’t know if it worked but that was the story.
Was debunked, it don't work
yeah that's an old bike racers trick, still works, too.
@@davidleggett137 wonder I'm going to have to cut all my primaries off cause paint disappeared on all 8 all the way down
I learned this trick as well and yes it absolutely works. White Chalk was used not paint.
it does work, and yes, it was paint not chalk. Flowmaster designed some amazing "collectors" that replaced the collector on a basic set of 4-into-1 generic headers and made them a Tri Y setup while adding length before the crossover pipe. but this video shows that just disconnecting the headers at the strip isn't getting the most power out of the engine.
thank you guys.... amazing!!
I'm shocked the Speedmaster even bolted up. We built a stroked Cleveland and at the time all we could get was the Speedmaster heads and intake. I swear, the guy designing the intake never once spoke to the guy designing the heads. It was disappointing, we would have been better off with factory iron heads.
speedmaster doesnt design or make the heads or the intake they are both chinese products they rebrand. the speedmaster heads used to be the procomp castings.
B Roll shot with Steve at the controls, and the dyno controller turned off had me laugh out loud.
Tighten up that lobe separation angle to 106 and see what happens...
Great show
I LOVE THIS $HIT!!!! 😊👍YOU GUYS ROCK✊️
Missed you guys at the Carlisle Chrysler Nationals. 😢 but Dodge thrill rides were there so all good. Lol
I HAVE MAD RESPECT FOR YOU AND STEVE DULCICH..... WHERE HAVE YOU BOTH BEEN ALL MY LIFE? I so long for the hot rod comrade
Clean up that flash and port match and it should improve. Idk if it would be enough to take top spot but it should make some gains.
My thoughts exactly, we would love to see the difference.
Junk
Needs a single plane. There wont be much casting flash on an AFR casting, but the head would flow more with a pocket port and agressive valve job over port matching
@@PackMane1419the test is to evaluate the intake manifold not the heads flow so cleaning up the casting flash and gasket matching of the ports on the manifold should help
with the power production on a budget . I'm interested in the results of such a test ! 🇺🇸🇵🇷🦊👍
@@ferdinandcuevas8457 agree with you. people forget that hot rodding isn't just bolting on parts like a mechanic. Intake manifolds are cast for a variety of engine requirements and should be tailored like a jacket to fit. if you know how to do that...then the cheap chinesum stuff shines so long as it's not porous.
I would like to see you test different types of root blower’s like stage 1,2,3,4,street , completion, street, hi helix. Teflon striped
you guys rock
ADD a Accusump - Oil Accumulator. Chnage LSA to 108
The og funnel Web was designed for a Cleveland with 4v heads and high rpm.
Just for fun I would of liked then to try a tunnel ram manifold and I've always been curious about those inglese weber set up's
Be interested in seeing what a bigger set of heads would do on that.
Big Block guy here. My 521 with factory cast iron heads all N/A went 750Hp and 9 seconds in the 1/4 mile. New build is a 545 Kassie aluminum heads with a Howards .800 lift roller cam. This one is in my Ranger truck build.
Wow y go aluminum, are 496 on pump gas with BBC 2 brodix heads made 780hp with port work, but on 93 octane
Yeah and it averages 5 miles per gallon 😂
😐
@@mariocooldude9092I'm sure as he was building it he was thinking of mpg.
Knucklehead
@@hughmongous5089 right because when I hear the number “521” in reference to displacement I think of economy cars 😂
Was hoping to see dual-plane versus super Victor on the 410
Curious what a real funnel web would do and not a cheap knock off. I’ve been eyeing them, and I wonder about the torker also, wish that one would have been tested. Most of us don’t have a 363 cubic inch 8.2” ford with cnc 225 heads lol. I wish I did!
thats like running 225cc on a 355 chevy. A little WAY huge for a street machine making the same power. However it works good on these engines because it is a way huge bore. And is an oversquare engine.
Thanks
What would happen if you ported the funnel web?
Love to see same episode with a chevy
I LOVE ENGINE MASTERS!!! I ALWAYS LEARN SOMETHING NEW!!!! I LOVE MY HOT ROD FAMILY!!!
Can you test older style intakes like the edelbrock torker II?
Why on earth the mismatched 113 degree LSA on the carbureted 363? Who specs this stuff?🥴
Would the funnel-web benefit from some clean-up and porting enough to be worth it, though?
That’s exactly what I was thinking. It’d be a good test for how much polishing and porting actually could improve it
Why would you bother doing all of that when you could just buy the better product
@@Lifeof728 it’s the cheapest one and working a die grinder is just time. Poor people gotta speed too.
well, that's the joke. Most people pay more for an aftermarket part to bolt on in place of the OEM part and call themselves a hot rodder (more like a mechanic, who just scans your car and keeps replacing parts until you stop showing up to complain about the problem). Old fashioned hot rodders would buy a crusty OEM part off a junkyard musclecar and then machine it, massage it, weld it into the design they need.
buy cheap, work it over in your garage, and keep up with the big spenders :)
@@H3110NU but its an intake plenum. You could grind all you want. If the design is bad, it will still under perform.
i didn't know about collector extensions 😎
I found that I could tune the collector length by shortening the collectors an inch at a time until I get the maximum power starting with an 18" extension and working My way down . 🇺🇸🇵🇷🦊👍
find an original funnelweb and match it to the intake. we run one works well for us. we spin lil higher tho dunno if make power up there but spins up nicely.
i am wanting to put a 351W in a 2nd gen camaro for my momma, because the deck hieght is 9.5" from the factory, unlike the SBC. . . Then again, may need to get an aftermarket block for the bore size anyway. Going to 4.165" bore size. and 3.8" stroke, 10.5:1 compression a 236*/ 238* cam @ O.O5O" lift respectively and a custom runner dual plane, and custom Tri Y headers and custom effective exhaust system with big truck size flowmaster 50 series mufflers. This exhaust system incorporates a special system before the mufflers.
I'd say the Super Victor and the Trick Flow are pretty much a tie with only 3 lbs difference in torque and 4 horsepower (approx). I guess it just depends on if the 3 extra lbs of torque matters to you or the 4 extra horsepower. Both would be hard to feel and see the difference at a race track. The difference at that point becomes the driver.
this is true, but if you match that slight hp difference with another one someplace else and the 10 hp with a pulley swap and a windage tray and so on...then it adds up.
You can hear the funnel bog when he lit it off...
I'd love to get my hands on the funnel web and match and clean it up
Id take a Windsor over a Cleaveland. I built a '79 360 nothing fancy just for better low end torque. Bored only .020 with stock cast dished pistons. A set of J heads with mopar performance springs for the mopar performance 268/272 cam. Holley 600 vac seconds, Accel 8mm wire and their super coil and stock rebuilt distributor. 2" exhaust to glass packs and stock manifolds to n sides. Be happy if it hits 300hp and at least 300 torque. Oh degreed cam 4degrees BTDC so cam comes to life earlier.
I would love to see a ford fe build with something like a torqstorm supercharger vs blower type set up. You don’t see this very often even tho they are popular motors
I would love it if the guys on Engine masters would build my 427 FE and then they could dyno for an episode. I have new, ready to build: BBM 427 Block, Forged stroker kit to 482 cubes, Edelbrock Proflow 4 Fuel Injection top end kit, Roller Rocker set, TFS Powerport 175 Cylinder heads, Hyd Roller camshaft. Just need someone to put it together, might as well make an Engine Masters episode of it. Yes David Freiburger, it would be great for the Ford FE enthusiasts see a street build like this. And I can't find anyone to build this for me that doesn't have a 2 year waiting list. Yes I know, shameless plug to get my engine built. LOL
watch richard holdener. He is a master and has done it all.
I would like to see the break-in procedure for a LS3/575
Any thoughts of it coming back to the rest of the world on MT?
I would go with D. Trick Flow Spec.
Cool that shop is down the street from here.....in yuma.....why dident u guys fix it ur self
How did we get from a 351 to a 302.
The 351 needs a open plenum intake and a 850 dp.
It's to bad they didn't do the funnel web after porting and cleaning up the casting that would be cool to know too
I would like to see what you guys can do with toyota 4.0 05 to 15. Motor. Port and polsh. Urd super charger. Or turbo, water methanal injection
So it’s essentially stroked, cammed and has a good set of heads?
Go with tighter lobe separation angle .
Play with a Holden 304 next.
Thank you.
Have you ever tested the Typhoon Dual Plane intake? I'm running one on my little 302.
th-cam.com/video/ihN-15Kn1BM/w-d-xo.htmlfeature=shared
I wish you had also done the funnel web after using 30mins with a diegrinder to hand port it.. I mean, that might have made a huge differance, and then at a half the cost?
Still would be behind by a good margin. 30 min portwork wont do much
What if you compared a BBC hydraulic flat tappet to a hydraulic retro roller cam with similar specs
I think with some light porting or heavy it depends on how bad a day that Chinese worker was having also a gasket match might not hurt I get this was an out of the box deal though so id be spending money on something that wouldperform without the extra manpower tho
熟练的人可以很快把它做得更好🇨🇳
That 410w has aluminum heads on it. Said static was 9.7:1 ..... Bump that static two points with forged slugs and you'd be easily over 500hp on pump gas.
Im part of the small family owned foundry in Australia that manufacturers the Parker manifolds. It's disappointing to see the support for a Chinese clone.
What happened to the first engine?? Video just switches from episode 120 to 110 halfway though...
Speed master with two hrs of Dremel tooling BEATS THEM ALL!!.ITS MADE FOR THAT..OUT OF BOX IS BAD..
And i believe we got "GACKED" In the dictionary now we did it man!
Port all the nasty casting flash off that Parker and I bet it does as good as all the others
Rescued the Disgustang 4/17/17
Can u do the Cla45 Benz engine
You HAVE to knock the flash off the intakes like you would in real life.
And either port match the intake or put a victor Jr on it
Port match that Funnel Web and clean up the flashing! I want to see what it can do.
Put same work in all intakes hr wise then run
Its nice to see a vid longer than 8 min. Maybe there learning again.
Funnelwebs have never been great. I know several who tried them and were disapointed. For a Clevo they may be ok as apart from a CHI intake there is little else around.The CHI will be better though!.
The Trickflow surprised though, better mid range.
It was a little weird when Steve started to say something about the original rpm air gap manifold not meant for higher rpms and they cut it short to fiedburger talking. 🤔
I don't know, after seeing the holley hi-ram 351w intake test on another channel. I would have to say efi may be the best chose. Even though die-hard ford fans are going to get mad.
I can't get mad either way none of these intakes fit under the hood of my 79 LTD Landau with it's 351 Windsor 😢
Ref the first clip (Ep 120) In another episode, you learned the double pumper made more HP than a vacuum secondary. If you're trying to eke out that last few HP, why not run the double pumper?
I'm very curious of why that Chinese manifold is the rage, in saying that anybody that's into racing would be port matching and cleaning up the deficiencies? On all of these manifolds? Just saying? Just a thought? Hey maybe there's something behind it? Just throwing that out there?
Idk if I would run Chyna without atleast Cleaning that edge up
When did engine masters come back to TH-cam?
can you do 400m build
Is it just me or did they just go to a totally different engine from the Windsor when starting out trying different intakes?
No, it’s not you. He clearly presented the other engine prior to performing the intake comparison.
THE DYNO DOES NOT LIE!!!! JUST THE FACTS AND ONLY THE FACTS !!!!
No Dave I don't have that much HP in my street car.Mine is abit lower. You see my 302 is bone stock ... Yup so true. But I'm not going too blow up my numbers matching motor and transmission. It tends too go with my survivor car my low mileage 5.0 GT .
Just a car brother run it and enjoy it, don't b scared it not chocolate, u will b dead by time it's worth big money
live a little, stroke that sucker to 347, at least.
@@alltherpm it's already worth big money!!! And I'm not scared too run it. It took me 10 years too buy it not because of lack of cash. I bought it from a 75 year old grandma friend of mine. She just wasn't ready too sell! Soi had too bide my time and be patient. Ford only made a tad over 28,000 of the 1982 2 door GT hatchbacks. Now there is not many left as nice as mine! so now why would I beat it , pound on it! There's no need too ! I enjoy it just the way it is . Mine is a survivor car NO RUST LOW MILES NEVER BEEN IN AN ACCIDENT! MINOR DOOR DINGS . 98% BONE STOCK UNIT I'm the 2 ND owner.
If you aren't making more horsepower than you are torque it means you have an airflow restriction. Probably either the camshaft headers or intake. Then again 195cc AFR heads would be terrific for a 302/331 but a 400+ cubic inch engine they are not flowing enough air.
totally agree what other info you got to help us beginners
Absolutely on the 410ci Windsor in the beginning of the video. Some AFR 220 heads,.675-.725 lift,108 lobe,250-260 @ .050 cam,bump the compression to 10.5:1-11:1 and a Edelbrock Super Victor... Easy over 600 hp on an engine dyno.
@@NCSTANGGUY exactly the motor I was referring to. It made good power but typically that kind of flat Dyno result between torque and horsepower shows there is a bottleneck somewhere. The factory 289/302 heads are a 165 cc intake port. I don't think the 195 cc AFRs are flowing enough.
also agree, even a skilled porter would help those 195cfm--there's dyno videos around here (richard holdener, etc) where cfm alone doesn't make power, it's the design of the port.
How can we get low rpm torque and hp
Woooow😵😵😵😵
Spend the $125 bucks and machine the AFR heads from the out of the box 58cc to 57-56cc and Wilson taperd spacer call it 500hp and done.
Ford - mercury made a 410 cubic inch engine. Have you ever dealt with it or have any history on it? I’m very curious about that.
RPM, the replacement for displacement.
how about a tunnel ram
As much as I recognize what a good engine the Windsor is , I,ve also heard of the blocks cracking apart when producing 450 plus HP .
The low decks will crack after 500 bhp, unless you can find one that bores past .040 over. But they were designed for economy cars and 221 cid, with the Y blocks for truck use. you can modify one to take way more power than that, and the tall deck Windsor will go 600hp on average.
th-cam.com/video/c71ClII1NsQ/w-d-xo.html
@@albertgaspar627 Tall deck being the 351 ?
@@barrycuda3769 assuming you mean the 351 Windsor, yes. There was the Cleveland and Modified (the 400M was the Midland, then it was destroked hence the Modified moniker) in that displacement as well, but i'll suspect you were referring to the Windsor :)
year of casting is important, Ford like most of Detroit cut down on nickel content in blocks from the late 1970's to the early 1980's. Some people will push the Windsor blocks a lot more (one right off the bat is the Neomustang channel here on youtube) and truck engines use better internals than the passenger cars, but that's a ballpark figure.
@@albertgaspar627 Yes, I did mean 351 Windsor, I watched the Steve Vizard video that you provided a link to, it's interesting that the cracking issues seem to be due to vibration, and that you can install aftermarket vibration dampening devices (girdles). I wonder if Chev and mopar small blocks have had any cracking issues? I'ts also interesting that the 289 powered GT 40's could complete the 24 hours of Le Mans with no issues, I know they didn't exceed 450 HP , but running hard for that long is impressive, but I imagine they had specially cast blocks? On the subject of Cleveland's I think in my part of the world ( New Zealand) we (Australia and NZ)had far more of them than in America, the most famous example being the GTHO Falcon , which has become insanely valuable. Maybe the Cleveland 351 is a better choice for getting big horsepower out of, despite being heavier , that means stronger???
@@barrycuda3769 Ford originally designed the 221 cid Windsor for economy cars (the Falcon) while saving the Y block for passenger cars and trucks with the FE/FT big blocks for heavy duty useage. However, Ford had wanted to make a corvette competitor in 1955 but the Y block was too heavy (so the Thunderbird got built on the family car chassis, the Fairlane). someone realized the 221 could be a sports car engine in 260 cid and handle midsized passenger cars, so the Y block went away and the 260 showed up in Sunbeam Alpines to make the Tiger.
Chevy, on the other hand, made its small block right from the beginning to power trucks and passenger cars, so they made it a bit heavier duty in comparison. Still, the Ford 289 had the impact you mentioned. It was designed to carry midwest americans at 70 mph for hours to their destination (compared to some european sports cars that got one around town, etc), but it was ultimately a good design. the cylinder heads ran smaller ports and valve sizes to build more torque at lower RPMs compared to the chevy, and the exhaust ports were sadly given short shrift as Ford designed cars with shock towers that took up space.
Mopar built its LA small block in 1967 off their A engines from the 1950's (LA stands for Light A) that spawned the first generation of Hemis. so their lifter bores have a bad cant for wedge engines, but otherwise you can guess the strength built in naturally. by the late 1970's, however, they were bankrupt so quality suffered. but the rest of the industry was getting hammered by imports, so they all put less nickel into their cast iron, and some engines were in fact lightened up in the main webs to generate more fuel economy.
You are spot on about the Clevelands. We got them "late to the party" and so there was less development--we only have two head designs to choose from, and engine builders will try to get australian heads. in drag racing, some teams would actually cut the exposed exhaust port off an american cleveland head and weld on a square pipe to lose the "dogleg" bend.
(on a side note, Ford did develop a version of the Cleveland with a taller deck height for use in pickup trucks and full sized cars like the Lincoln to theoretically get rid of big block engines. they were the 400Midland and later a destroked version, the 351Modified. it's a shame no one bothers to modify these engines, there's a fair bit of potential in each one even though the rear of the block only has a bolt pattern for heavy duty transmissions).
considering the taxes, shipping and exchange rates, if i lived in your part of the globe I would go with a cleveland. unless you needed a roller cam setup and your windsors offer that right from the factory--that's what we have here, and it's worth buying a windsor engine from a junkyard and getting the entire roller cam setup for free. plus that model got EFI from the factory, which also saves eventual costs if one wants that and isn't getting too crazy with the engine build. plus our ford explorer SUVs came with the best OEM windsor heads on them stock--the GT40P heads once offered over-the-parts-counter. so you grab a set of those on the way out the door, and you have yourself a decent street engine to put together for a hot rod.
Turn the pistons around.
The 1970 Chevy LS-6 454 was rated at 450hp/500 lb. ft torque, and no one complained.
Progress marches on.
@@glengabruch4664 It is interesting that some people modified the cars and I was one of them but others leave them stock. They are safer, faster and more fun modified but the original cars are truly special and worth the most. The untouched LS-6 cars.
Port and test the funnel web
Mythbusters for engines!!!!
No mopar small block?
You could double the hp with rotary valves instead of conventional valves
Why did you send it out to get rebuilt since you have the knowledge?
either time limit or....most of the parts you see in these videos and on PowerNation TV come free from the manufacturer in return for free ad time.
E4TE block
Can you run 6 inch rods in a 350 block with stock 350 Crank
Of course you just need pistons with the piston pin height designed for 6” rods.
@@stevewalters6853 thanks for sharing this with me love the videos
@@stevewalters6853 so do you think 6 inch rods in a 350 bored,over .40 is a good idea
@@Catheysoutdoors2949 According to dyno operators no different power from 5.7 to 6” but might make for a lighter rotating assembly with the lighter piston used with 6”. For a street car I’d just stick with the 5.7.
Yep. Just has a shorter compression height (the pin is closer to the piston top).
USA#1!!!!
My understanding is a square engine should be about even in HP and torque. Did I miss something?
Surprised they didn't use a dual-plane intake. On a different episode comparing single-plane with a dual-plane, the dual-plane performed better on a street engine.
You said it on a "Street" engine the dual plane is great. On this engine going to 7,600Rpm, the dual plane would get smashed in high end hp, as this setup is geared for racing. Sure the dual plane would have the most tq. down low, but anyone that knows anything about racing, would use a 5,500 to 6,000Rpm high speed TQ. converter on this setup, shift @ 7,500 to 8,000Rpm, and never look back!
Idk about anyone else but I’d love to see these guys build an extremely high compression engine maybe like a 406 Chevy. My neighbor had one that he ran off aviation fuel that had a very high compression ratio. I want to say it was like 18:1 compression but it could be a little lower than that.
probably 14:1 to 15:1. 18:1 is diesel territory.
edit: somehow my later response got lost or deleted, so i'll just add it here: in the late 1970's Bruce Crower had a mileage cam idea, you used 14:1 or so compression pistons and one of his cams that closed the intake valve really late, like almost near TDC. it bled off compression into the intake manifold on purpose, but at higher rpms it had less effect and you got higher compression for fuel economy and power. but what you really got was a soggy power curve at cruising RPM and domed pistons that blocked much airflow into the engine at higher engine speeds. so it was a lose-lose situation.
@@albertgaspar627 yeah diesels have to have that high for igniting their fuel but in theory couldn’t you make a normal engine have such a high compression?
In theory, but you need fuel that is knock resistant enough. Even Avgas wouldn't be able to handle 18:1. Maybe if you were running on methanol and using other tricks to prevent knock it could work.
RE. super high compression on gasoline. Need to understand static vs dynamic compression. Running compression is reduced by factors that inhibit volumetric efficiency. A example is a 2bbl limited engine class, can't fill cylinder at higher RPM. Cam timing is adjusted to lower compression at lower speed.
@jeffhill3681 yeah you can look at the inlet valve closing event timing to get a sense of this. Later IVC moves the power band higher in the rev range and reduces the effective compression ratio at low revs, while raising it at high revs.
A particularly extreme case is found on the Toyota Prius engine, which always closes its inlet valve way too late. Net effect is to reduce the geometric 14:1 or so compression ratio to something normal 91 RON fuel can handle. But the expansion ratio on the power stroke remains 14:1, so the engine extracts more of the energy from the hot gases than a regular Otto cycle. Of course this means the volumetric efficiency and thus power is rather low, but it's a hybrid so the electric motor compensates for that.
The other side of the coin is diesels, where making the IVC happen too late makes the engine impossible to start because the dynamic compression is too low at cranking speed.
Those port corners are dead air space anyway.
Look up wetted diameter.
Why not run rpm you actually use on the street below 3k?
if, and when, (as always in america) you got an auto trans there. With a 7500 winding smallblock, you kindof need a 3000 stall turbine. If you mash the throttle, the turbine lets the engine always go to 3000rpm, and start pulling power from there.
Manual guys, like I, are a different story