Crunchy_NuT

ok new to this site hope you boys dont bite too much

as a couple of you might know - im awaiting the arrival of a HT prem (if there's ever a christmas in july, im the little kid packing himself waiting for santa...lol)

so far the ideas are applenty but i keep coming back to a 383 - which is where my problems lie (already i will upset people by sayin no to a LS1/2 transplant - already got one of them in another car)

i've been told that a 400 sbc de-stroked to a 383 is the best option to go, my questions are aplenty, do these rev hard? can these be done with low compression (in case of future forcing pathway)? heating probs still the same? reliable? better to just stay as a standard 400? technically it should have more torque than a stroked 350, but is it really worth the hassle?

really i want some people to give pro's and cons on the choice i'm deciding on...hopefully someone out there has the exact setup and can share some knowledge

cheers all and thanks in advance

greenhj

a 350 crank in a 400 makes for a 377, which would be a good revver with good torque.

3554me

i have a mate with a destroked 400 but it's a 377 and it fly's mate , u cant go wrong with the big cubes.

struggler

A 383 is a 350 stroked with a 400 crank. The 377 is a destroked 400 using a 350 crank.

The 383 will make more torque below peak power, the 377 will make more power after peak power. The difference really isn't much, about 2 or 3% either way but the 377 will hang in there longer after the peak where a 383 will drop right off.

My engine is a 377.

JMHO

BossHoggett

Yea its possible, its not popular to my knowledge today. Most Pro stock or sprint car engines making 10-12,000 RPMs were 302 chev cranks or turned down 327 crankshafts in the 70s, I had the same fascination years ago too. The bore to stroke relationship coupled with the custom conrods of preposterous Lengths and a low compression engine.....is arse about face and a waste of money.

Crunchy_NuT

sorry guys - i stand corrected

struggler - your line about where a 383 will drop right off has just convinced me which way i should be heading - i've had enough of lag, ls1's boggy bum has got to me


obviously these can be boosted like any other motor - how about cam selecting? run with much the same selctions for a 383?

im an old school engine newby you could say

gas 84k

Dependiing on what heads you choose and valve angle there is less valve shroud with a 400 why would you want to destoke a 400?With the right combo they make 650 under 6500 with over 500 ftlb at 4500 on.With pump fuel.

allports

2nd that. Our little flat tappet combo Torana on BP98ulp made 510 on moroso on the weekend still too fat turns to 6800 ran 10.1 @ 132 with 3.7 gears no trans brake. Its got an old 2975 vic jnr and a set of racer pro alloys.

__________________
If you plant a cucumber, you get a cucumber!
Two things are infinate,the universe & human stupidity, and Im not sure about the universe.
Albert Einstein
Without deviation from the norm, progress is not possible. Frank Zappa

gas 84k

That thing would be making the big dollar boys stand up and take notice!

allports

Nah out at wsid most of the guys run gas gas gas gas gas gas gas gas gas gas and just to make sure they gas it.

__________________
If you plant a cucumber, you get a cucumber!
Two things are infinate,the universe & human stupidity, and Im not sure about the universe.
Albert Einstein
Without deviation from the norm, progress is not possible. Frank Zappa

gas 84k

How do they race with all the lafter

Crunchy_NuT

thats once all the brains are fried - get immune

Crunchy_NuT

thats impressive

struggler

Well I agree with the valve unshrouding, thats one reason why I went to the larger bore.

I was running a 350 but the bore was a bit worn. I had to bore and hone and buy new pistons anyway and I had the 400 block in stock so I got pistons for the bigger bore that weighed similar to my 350 slugs and bored the 400 block. A set of spacer bearings and I was away with 20 odd extra cubes. If I wanted to build a 400 I would have needed an external balance balancer and flexplate and a balance as a minimum. Hell I'm glad I built a 377, a 400 would have been too fast, the 377 is too fast as it is !!!

At the end of the day if I wanted to go as fast as possible and had the money I would have built a 400. I didn't so I built what I could afford.

Allports : Good work with the Torana, did you used to race a hatchback LX at ECR back in the day ?

ONN20

Was sort of Torana is it Allports? What does it weigh?