Mangled03gmc

iTrader: (95)

Does the truck 496's come with aluminum heads or steel, also what is the comp ration on them, thanks for any help. John

nightrunner

iTrader: (4)

i know they are cast-iron heads and the only aftermarket heads i know of are the raylar aluminum heads and the reason i heard they are so expensive is because they made their own casting

comp. ratio is 9.1:1

Mangled03gmc

iTrader: (95)

Yah i am not up to spec on the 96's too too much, I am looking for a pair of engines for my boat, found a set on a offshore site, The seller sayd they are merc marine engines, I know that marine engines come with steel cranks, this guy is saying they have cast cranks, so that makes me think they are just from gm,also raylar makes good chit for the 96's.. Is the cranks in the truck 96's engines forged or cast?? thanks JOHN

nightrunner

iTrader: (4)

i got the stock info from the chverolet site fyi

i found the raylar stuff when i was lookin at the trucks for my dad (got a dmax instead)

not sure on the crank but 95% positive it is NOT forged does any stock motor from gm (excluding ls7) have a forged crank stock

probably cast

i think the pistons are that hypereutitic (sp?) very fragile from what i hear with nitrous and FI

Mangled03gmc

iTrader: (95)

Thanks, i am almost 100% positive that the gm marine engines(merc) come with steel cranks. Raylar is big in to marine hop up kits, for the 96's, also has kits that get over 530hp out of them, with no blower or spray..

ANYBODY ELESE John

dirt track racer 81

iTrader: (45)

had a 2003 8.1 on th dyno the other day and made 188 rwhp on a mustang dyno

nightrunner

iTrader: (4)

damn that allison must really rob the power

gm rates them at 330hp i think stock

dirt track racer 81

iTrader: (45)

but it also made once i got done tuning it it was at 220 to the rear and 278 tq

nightrunner

iTrader: (4)

wow thats a pretty big jump with just tuning