wildn347

iTrader: (19)

i keep seeing ppl say they have 5.3 heads on there ls1 does it bolt right up without any modification if so does it get a decent amount of power?

bryan04h

iTrader: (2)

https://ls1tech.com/forums/showthrea...&highlight=5.3

there is a lil info on them, it will bump up your compression, but at the same time you are going down in size with your valves...eh, it is just a bit better flow..if you are looking for cheap heads then cool..but i would recommend aftermarket heads

wildn347

iTrader: (19)

so they can go on with no modification at all?

wildn347

iTrader: (19)

and if you switch over to 5.3 heads would you also have to switch headers or would ls1 headers work like to get as much info on this as possible

RE AND CHERYL

iTrader: (31)

The only difference in the 5.3 heads are the valves are small and the combustion chanber is slightly smaller yielding about 4/10 of a point bump in compression. If they aren't ported, don't bother installing them.

Re'

green28

iTrader: (8)

Just totally curious and might sound stupid, but what about putting stock ls1 heads on a 5.3 motor? Any significant gains or loses. I've always wondered if it worked both ways.

bryan04h

iTrader: (2)

the answer is yes they are interchangeable heads..but they will lower the compression ratio where as 5.3 heads on a ls1 rise..

1994Z28Lt1

iTrader: (1)

stock ls1 heads on a 5.3 will lower the power because of the decreased compression and because of the slightly lower flow in stock form but im sure they might be great heads to have fully ported on a forced induction iron block 5.3

adillhoff

They're all right. I bought 5.3L heads because they fit well for a mild cam and my mild college budget. If I could do it again I probably wouldn't buy them. Definitely get them ported. I got a nice job on mine with bigger valves and they put out enough power to make me happy.

2000_SS

iTrader: (24)

i picked up a set of PRC stage 2.5 5.3L heads from a member on here. brand new paid $800. TSP sells them, supposedly a badass bang-for-your-buck. i'm deadnuts in the middle of the install right now, so i can't verify that. but even for the ~$1300 price tag, they're well worth it. they advertise 315cfm @ .600" lift and will bump compression to ~10.75:1....not too shabby.

SweeTbone

iTrader: (8)

Definitely get them ported. I have the PRC Stage 2.5s, and it's a top notch piece for being on a budget of sorts. #s in sig.

bryan04h

iTrader: (2)

i've seen quite a few ppl put up big numbers with prc stage 2.5's there is nothing wrong with those heads by any means!!