4.8L Crank + 6.2L Block = 659 HP (Dyno Tested!)

Рет қаралды 7,265

2 жыл бұрын

CE Performance Crate Engines combined the 400 SBC and 327 SBC type bore and stroke combination, after what was learned with our 354 cu.in. SBC (327 crank in a 400 block), and created an engine, a 349 cu.in. LS with a 6.2L block, bored to 4.125", and a 4.8L 3.267" stroke crankshaft, that produced 1.889 horsepower per cubic inch - an awesome accomplishment!
This build included:
- GM 6.2L aluminum block bored to 4.125"
- GM (stock) 4.8L 3.267" stroke crankshaft
- Eagle 6.3" H-beam connecting rods
- AFR LS3 260cc rectangular port cylinder heads
- Edelbrock Super Victor LS3 intake manifold
- Solid roller cam
- 12:1 compression ratio, runs on pump gas
Previous 349 LS videos:
The 349 LS road tested in a 1971 Chevy Nova: • LS 6.2L Block + 4.2L C...
Two engines: • 468 LSX, 349 LS Discus...
327 Crank in a 400 Block ("The 350 that Chevy should have built") playlist:
• “The 350 that Chevy sh...
A huge thank you to Kyle and Jim of Richmond Engines!

Пікірлер: 45

@andyharman3022 Жыл бұрын

When you get down to fundamentals of engine performance, it's bore size that determines power potential. When you destroke, you get the power back by revving higher. Then the limit becomes how much money you're willing to spend on an 8000+rpm valvetrain. But i love destroke engine builds. Next thing I'd like to see is a 302 LS with 4.125 bore and 2.825 stroke.

@ceperformance Жыл бұрын

Yes, absolutely. Thanks for commenting!

@sepg5084 2 жыл бұрын

Would it have more power if you used a 6.2 liter crank, keeping the compression the same?

@ceperformance 2 жыл бұрын

Thanks for the question. A few things would have be different such as rod length, compression height (meaning wrist pin positioning) to name a couple. The total horsepower would not be higher in my estimation, especially the HP per cubic inch I believe would be way way lower. However, the long stroke would definitely make more torque, and all of it at a much lower rpm. Different engine combinations are fun to explore and this one has been quite special. Thanks again for commenting!

@joeyjojojr.shabadoo915 Жыл бұрын

More people need to see this video. THIS LSx bottom end combination is my 2nd favorite, after the 387cu (same bore, substitute a 3.622" crankshaft). As you said below, the HP per cube probably would change as much as an earlier TQ curve with the 387, but I would venture to say that with proper LS7 heads and more camshaft, the 387 would easily make an additional 150HP overall with a much sexier TQ curve down low.

@ceperformance Жыл бұрын

Thank you for commenting! Have you built a 387 before? It would be interesting to see the differences on the Dyno, for sure.

@joeyjojojr.shabadoo915 Жыл бұрын

@@ceperformance I haven't built either the 4.125" bore/short stroke 350 or 387 before as an LSx block or sleeves were out of my budget and I never had the courage to have an LS3 block taken much past 4.080". I am however a big fan of the cheap 4.8L Iron and my next build will be taking the iron 4.8/5.3 block out to 3.905/over bored LS1/6 with the 3.268 crankshaft. Like you, I am a fan of off-the-shelf parts and I love the interchange (ie. 3.622" stroke 6.125" rod = 3.268" stroke 6.3" Rod = same Pin/Comp height). The smaller cube 313 will also be small enough to simply run ported factory 862 heads, without needing to spend too much on aftermarket, other than valvetrain. I just love seeing more stuff done in Canada. I am sure there are more Canadian builders out there that don't have time for KZfaq though.

@ceperformance Жыл бұрын

Don’t sweat it on an LS3 bored 4.125. They do start life out at 4.065 as I’m sure you know. There’s plenty of iron left and a bunch of aluminum beyond that too! I hope your future builds yield big power :) Thanks again for commenting.

@joeyjojojr.shabadoo915 Жыл бұрын

@@ceperformance I guess that makes sense for an NA build, as I have even seen buddies dare to bore their 6.0L iron blocks out to 4.065" as the 'Poor Man Iron LS3' and as long as they keep them away from positive manifold pressure inducing items...lol... they seem to live quite well. The 313 I made reference to above is simply something I haven't seen anyone do and an LS1/6 over-bore 4.8L is interesting, as I also said, it's cylinder head requirements are well within it's own stock castings with a bit of massaging. While I don't see 500+ HP in it's future, with enough cam, valvetrain and 8000RPM, it might knock on the 450HP door at least, judging from what I have seen with just an NA 4.8L built properly and now that Summit sell 6.257" H-Beams with ARP hardware, I can even use someone's LS1/6 throw-away/upgrade-leftover stock pistons if I want to do it REALLY cheap.

@ceperformance Жыл бұрын

@JoeyJoJoJr.Shabadoo Well I totally agree with, “give it a try”. If someone isn’t willing to try different things then we’re not learning much. I’m interested in building different combinations with off the shelf parts, sometimes on a budget but sometimes not. I’m interested in the Summit rods you mentioned. Would you have a link or part number?

@tuckerc3802 6 ай бұрын

Dumb question but does the shorter stroke make it harder on the crank and bearings because its spinning faster and less rotating mass and dwell or is it better ..??

@ceperformance 6 ай бұрын

Hey, thanks for the question. Remember that the crankshaft isn’t spinning faster ‘because’ it has a shorter stroke. RPM is RPM no matter the stroke, rod length or piston height. The long rods are an advantage in the piston life department being there’s slightly less side load on the skirts. The advantage of the shorter stroke with the longer rod over a longer stroke with a shorter rod is about geometry and piston speed (acceleration, deceleration & dwell…). To really get a great explanation I would suggest watching this video on the Driving 4 Answers channel. Dude is brilliant :) Cheers. kzfaq.info/get/bejne/ecWJgdFkv9GunYk.htmlsi=NOP0BhAQIG3vwRmN

@cartermackenzie1135 Жыл бұрын

What cam specs did yall use? I'm trying to learn how to pick the right cam for this application.

@ceperformance Жыл бұрын

Thank you for asking. The specs I think might be in the video description, or the video posted after this one. I’ll check.

@ceperformance Жыл бұрын

4.8L Crank + 6.2L Block = 1.889 HP Per Cubic Inch 349 LS (extended cut) kzfaq.info/get/bejne/qtp1psiTys7Iopc.html

@ashleighsmith6755 Жыл бұрын

Nice numbers Is this built for Drag racing? Thinking of doing similar with Higgins cnc 862 Heads. Is this with 6.2 Rods Cheers

@ceperformance Жыл бұрын

Mine is a street engine. Runs beautifully on 94 Chevron gas. We used 6.3” rods. Thanks for commenting :)

@ceperformance Жыл бұрын

Here's a link to us taking a Sunday drive: kzfaq.info/get/bejne/gNh3dqSFksu6mnk.html

@ashleighsmith6755 Жыл бұрын

Cool Yer I’m looking at doing a high compression NA higher mid range TQ. Track/circuit car only use.

@ceperformance Жыл бұрын

@@ashleighsmith6755 You're welcome to contact us via email, ceperformance@hotmail.com for further inquiry! Best regards.

@gtgodbear6320 Жыл бұрын

I Like Short Stroke Motors. I would like to see a 4.0L LS/LT design short block. Same bellhousing. Beefed-up Billet design just with a shorter deck. Custom short Stroke crank & beefy pushrods. You can use LS/LT heads, cam, intakes, headers. 35+lb of boost and 8,500+RPM's might be plausible with that little engine. It would be great in a small car like a AE86 or Miata.

@ceperformance Жыл бұрын

Sounds like fun! Thanks for commenting :)

@machwind3266 2 жыл бұрын

12 to 1 on pump gas. Do you have a specific grind on cam to accomplish that? I dont know much, Im old. I suppose you can vary the timing during the rpm band, too. The electronics available these days were not available during my day. Its interesting to see todays engines produce the power they do and the ease at which they are tuned. But, it requires thousands of dollars of supporting electronics to tune the motor on the fly!

@ceperformance 2 жыл бұрын

Hey, thanks for commenting :) On these modern engines, higher compression is achievable with pump gas because they are not as prone to detonation. Flat top pistons, small combustion chambers because of lower valve angles and of coarse aluminum heads, are all beneficial. You’re right that cam specifications also have a lot to do with successfully reaching your pump gas goals. This particular build does have a custom cam with a lobe separation of 114 degrees, .714” valve lift with 256/268 degrees of duration @ .050 lift. The amount of timing is also a good point. I think we finished at about 34 total.

@rs3672 Жыл бұрын

@@ceperformance Question on this engine and cam - the specs you listed above give a +34 overlap, but at idle the engine seems pretty smooth? Maybe due to the video quality or because its on an engine stand, but I would have expected a crap ton of chop at idle. I have a Porsche 996 with an LS3 dropped in and I'm looking for something that has a different power profile than the GMPP hotcam crate engine I have.

@ceperformance Жыл бұрын

Thanks again for commenting. I am very happy with the idle quality of this 349. The trick is wide lobe separation (as far as a performance grind is concerned) with 113LSA. The factory hot cams I think are quite tight. I find that the popular BTR cams are that way as well and I really don’t like it. Sure it makes a bit more top end power but I think it’s giving up too much down low. Always a balance :)

@mohanperformance.enginerd.1308 2 жыл бұрын

I would like to see The next one be a std deck block. 4.200" bore 3.620" stroke. Local flowed LS7 head T&d's or jessel with.... .8" int lift & ti valves. 13 to 1 compression. On pump gas. "Large dia" IR 8 stack. Holley efi. 😊

@ceperformance 2 жыл бұрын

That sounds like a beast! Are you thinking of a LSX block or something else? Any predictions on the power? Thanks for commenting!

@mohanperformance.enginerd.1308 2 жыл бұрын

@@ceperformance Sure. LSX iron block will work fine for that. Power ofcourse will mostly depend on induction choices. 13 to 1 is getting daring. But I believe with the right touches and parts. It is very doable on pump gas. My thought is to chase the other side of 2.0 per inch.

@ceperformance 2 жыл бұрын

I’m very interested too :) We should talk!

@Lagrange1186 Жыл бұрын

Makes me wonder what can be done with a 383 5.3 build. Always love a wolf in sheeps clothing builds. Nice job

@ceperformance Жыл бұрын

Thank you for commenting! Most people don’t understand why we’d make a big bore engine smaller displacement and not as big as possible. Myself, I think this combo is quite impressive as a street car, pump gas engine. It’s very fun in the stick car we jammed it in :)

@ceperformance Жыл бұрын

Check out our 383 LS videos: kzfaq.info/get/bejne/q6eYgMKfqLPViIU.html and kzfaq.info/get/bejne/bd15i7mA3bK4aGQ.html

@kennethalbert4653 Жыл бұрын

Impressive ! I love the big bore - short stroke combos. I'm old so I still prefer the small blocks even tho I recognize the superiority of the LS. Cathedral heads or LS3 ? or LS7 🙂

@ceperformance Жыл бұрын

LS3 AFR Heads :)