flippindabird

i have an 02 Z71 with a 5.3L im looking to upgrade for more power and get a fresher engine with less milelage (has 175k now) first question is how much better are LS1 heads then the 5.3L heads? i heard that the 5.3 heads raise compression on an LS1 and flow the same... is this true?? reason im asking is i want to know if i should keep the stock heads, have them rebuilt and swap the 5.3 shortblock and the 5.7 shortblock. next how much cam is too much cam?? im going to do this as cheap as possible, this means a stock style cam, i was originally going to swap in a 98-00 LS1 cam (210ish dur and 500ish lift) because this truck is a daily driver, 4wd and i didnt want to replace the stall converter, but i have seen ppl with 4.8L use the LS6 cam(220ish dur and 525 lift) with the stock converter, im thinking maybe a z06 vette converter??? is there a difference between a truck converter and a car converter??? more info... i originally wanted a 6.0L but i found a good deal on an ls1 shortblock, really just wanna know what heads and cam would be a good compromise of power/torque and driveability in my truck, please keep in mind it weighs around 3 tons, thanks for any help

Bumpstix

bump... i have the same ?'s

babbage1109

iTrader: (11)

Ls1 bottom end with the 5.3 heads and a ls6 cam will be ideal. And get a ls6 intake you will be set.

fst_ls1

iTrader: (1)

me too...any one have any good info?

atli126

iTrader: (1)

.... im in for more info too

tommyd2006

Well if I was you I would get a motor from an 07 up truck with a 5.3 and leave it be it will be good and reliable and alot cheaper than peicing an old motor together

shorty(98TA)

X2

Im planning the samething for my lifted 04 Avalanche. You can run your stock converter but I plan on upgrading mine while I have the motor out

flippindabird

alot more money and less power. ill gain about 20 hp over my stock '02 5.3L... these engines are still relatively new and expensive. i can get an Lq9 for the same price as one of those. the point of the LS1 bottom end is to add displacement, and do it cheaply the ls6 cam as well... the whole point is bang for the buck

oh yeah, the LS6 intake doesnt give you much gain if any over the stock truck intake... the only need for it is if you need to fit it in something with less room then a truck engine bay... also you cant just change the intake you need to mod the waterpump/swap it out for a vette wp ANDshim the pulley, then get different fuel rails or mod yours, couple of other small differences between the truck and the vette/f body... alot of money and work for very little gain. if you have an fbody or vette itd be a good idea, but for the amount of money alone, its not worth it in a truck imo

shorty(98TA)

With a LS1 shortblock and LS6 intake why not just run a Fbody waterpump instead of the vette wp and modding the intake?

flippindabird

i myself already have a truck with the truck wp and such so it doesnt make sense for me... for someone with an fbody its not a big deal i guess

shorty(98TA)

mite be if that someone is asking for info on a LS1 swap into his 04 Avalanche

flippindabird

gotcha... kep your truck intake, or get the fats 90... ls6 is more money then its worth, truck intake outflows the ls1 intake the ls6 outflows the truck intake, the fast90 outflows all of them, for a few hundred more then the ls6 intake youll gain ALOT more... and after you convert to vette or fbody wp and accessories then youll be closer to the cost of the fast intake, ill get a link from "performancetrucks.net" on installing the ls6 intake on a truck for you when i get some more time...

garygnu

comp 54-408-11 cam,comp 918 springs,harden push rods.whats the casting number on the ls1 heads ?keep the truck intake.

shorty(98TA)

I did some searching in preformancetrucks forum and havent found what I was looking for yet. So I just took the oportunity to hijack this thread before they lock it for being in the wrong forum

flippindabird

ive heard all the cool kids are using trailblazer SS intakes on their trucks these days