How much power will a 4.8 hold?
Jul 25, 2003 | 06:29 PM
#1
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From: St.Louis
How much power will a 4.8 hold?
Just wondering how much power a 4.8 will hold up to before it breaks. Does anyone know where I can get the full specs of the 4.8? What kind on internals are in them, forged? I have a freind with a 4.8 and I am building a custom turbo setup for it and Im just wanting to know how hard I can push it. Thanks for any info!!!
Jul 25, 2003 | 06:32 PM
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From: Azle/Saginaw, Tx
Re: How much power will a 4.8 hold?
texasterminator is the only person i know of that's blown one up on prolonged supercharging. FAST4.8 blew one up(i have it now) but that was a dry nitrous shot blow up. i'm thinking of building a forged heads/cam/nitrous 4.8 for a different project not a truck.
Jul 25, 2003 | 06:53 PM
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Re: How much power will a 4.8 hold?
No forged internals. I think the pistons are cast 
and the rods are powdered metal(pretty strong).
As far as power capacity, the crank and rods should be fine for quite a bit 500+??. I don't know if anyone has destroyed a 4.8 from just power output, more than likely tuning was more a factor. The pistons will take quite a bit as long as they don't see any detonation.
and the rods are powdered metal(pretty strong).As far as power capacity, the crank and rods should be fine for quite a bit 500+??. I don't know if anyone has destroyed a 4.8 from just power output, more than likely tuning was more a factor. The pistons will take quite a bit as long as they don't see any detonation.
Jul 25, 2003 | 06:57 PM
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From: Deep in the seedy underworld of Koonerville
Re: How much power will a 4.8 hold?
Here is a site with a little info on the 4.8L.
Basically just the bore and stroke.
http://www.gm.com/automotive/gmpower...ehicle/lr4.htm
Basically just the bore and stroke.
http://www.gm.com/automotive/gmpower...ehicle/lr4.htm
Jul 25, 2003 | 08:11 PM
#7
Re: How much power will a 4.8 hold?
Ther was a guy that did a heads and cam with prochargert hat was in the 370 range and it died on the pistons I believe. Texas Terminator maybe?
Mine blew up at about 350hp due to a lean n2o shot.
Mine blew up at about 350hp due to a lean n2o shot.
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Jul 25, 2003 | 08:23 PM
#8
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From: St.Louis
Re: How much power will a 4.8 hold?
Yea,
Im fairly good with tuning if I got a good system to work with. I plan on using an intercooler and Alky/Water injection on it to keep from burning up the pistons.
I think that I could get 425 RWHP no problem.
Also,
Are the fuel systems on the trucks like an LS1? With the in-tank regulator?
Im fairly good with tuning if I got a good system to work with. I plan on using an intercooler and Alky/Water injection on it to keep from burning up the pistons.
I think that I could get 425 RWHP no problem.
Also,
Are the fuel systems on the trucks like an LS1? With the in-tank regulator?
Jul 25, 2003 | 08:27 PM
#9
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Re: How much power will a 4.8 hold?
The fuel systems are not the same. The regulator is on the side of the drivers side fuel rail and is manifold referenced. Evidently it doesn't raise pressure 1:1 under boost but, does raise it some. I think parish8 said it was like .5psi fuel/1psi boost. Fuel pressure at idle is like 50psi and rises to 59psi at 0 manifold vacuum.
We actually have a nicer fuel system than the Fbodys except for the crappy little injectors GM stuck us with.
An intercooler and water/alky will be AWESOME.
We actually have a nicer fuel system than the Fbodys except for the crappy little injectors GM stuck us with.
An intercooler and water/alky will be AWESOME.
