How well do 383s do under boost?

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Jul 29, 2010 | 04:51 PM

IWGF

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From: Aztec, NM

How well do 383s do under boost?

Good? Bad? Reasons?

And if any of you guys are running a boosted 383, what are the specs on your motor and FI setup?

Reason I'm asking is because I'm planning on doing a 347 w/ a 76mm Truck Mani kit and one of my friends asked 'why don't you just do a 383?' so now I'm asking because I don't know why you wouldn't do a 383 right?

Thanks guys

Jul 29, 2010 | 04:59 PM

RCC

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From: Willis Texas

Thats a really open question. As its really the parts and assembly of a motor that makes it boost friendly rather than the cubic inch. But to answer your question about 383ci motors and boost, LMR finished this rear mount C5 with a 383 recently and this car makes stupid power, the car made 1200rwhp with a single GT47-88.

Heres the thread about it

https://ls1tech.com/forums/texas-mem...-1200rwhp.html

Jul 29, 2010 | 05:01 PM

MIGHTYMOUSE

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From: Virginia

383 would require you buying a crank.

considering you would be on 4 bolt heads i dont think it would be getting you much more than being able to say its a 383.

also raising cubes does not raise how much hp a turbo can make...tq yes.

Jul 29, 2010 | 05:42 PM

IWGF

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From: Aztec, NM

Quote:

Originally Posted by MIGHTYMOUSE

I know I'd have to buy a crank.

So the difference between a 347 and a 383 is fairly minor when we're talking FI then?

My original plan was for a 347 w/ about 9.5:1 and a small custom grind boost cam w/ a Precision 76mm on a truck manifold style kit.

Sounds pretty solid I think. Opinions?

Jul 29, 2010 | 05:44 PM

castine917

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From: middleville,mi.

a fellow in a local club was running a 383 in his 69Z @8.99. still street driven too. good luck finding any online info on his car though. can find him on ------------------------- tell him chad castine said to ask. he might be willing to share some info then or maybe he will just beat me up.

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Jul 29, 2010 | 10:43 PM

TurboS10

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From: Waxahachie, Tx

I'm doing the iron 347 with ported dart heads and a mid 220 cam w/ twin 61mm.

Jul 30, 2010 | 02:20 AM

venom ws7

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From: EARTH

IMO if you went with 383 then go with bigger turbo....
And yes if the 383 was built right it will handle a lot of boost like RCC already posted.

If I had to choose I'd keep the 347 or go 400+ci.
I'm planning to keep my 347ci 8:5 compression (I'm rising the boost a little though 8:8)
and going with something between 80-85mm turbo (depends on what I can fit on the damn Vette)