Ferocity02

iTrader: (60)

I am looking at getting some heads and have found a pretty good deal on some Stage III ported and polished LS6 heads. They have 2.080 intake and 1.60 exhaust with Crane dual valve springs and a 72cc chamber.

I am thinking that these heads are too big for my puni cam. The fact that the chambers are 72cc is bad enough. Can a head this big actually hurt performance. I think its more for a blower application than a N/A one. Thanks.

jrp

iTrader: (16)

you'll need to mill them .030 just to get them back to stock compression. what are the port volumes on the heads and what bore are they setup for?

Ferocity02

iTrader: (60)

They are stock bore and I don't know what the port volume is

slow trap

iTrader: (22)

i've been wondering about power also.i'm sure bottom end will suffer but was wanting to see a comparison between s2 and s3 heads with a small cam and larger cam also.with that big of a intake valve p/v clearance may be an issue with a healthy cam.

ForceFed HP

are they true LS6 heads? casting 243? cause a true LS6 heads with a 72cc chamber is probably not setup for stock bore and a 2.08 valve in a stock bore is shrouded like mad.

Ferocity02

iTrader: (60)

I think they are true LS6 heads, they came of a Z06 I believe...

So the notion that I am getting is that stage III heads are more for a big bore or stroker motor, or FI? Is this right?

dug

iTrader: (10)

Youre gonna want a cam with more lift when running ported heads.

goober35

iTrader: (1)

If the are PP head they are 317 6.0 heads. I have never seen a 72cc ture 243 ls6 head. I have a 66CC chamber ls6 243 head and that is about as big as i have seen. I would think those heads are flared out for a bigger bore than a 3.898 or what ever stock is. I think that 2.08 intake is going to hurt your volosity so you will be down on some power with that and the 72cc chambers are not going to help eather. I would look for a2.02 intake at the biggest with a N/A 5.7 unless you want to runs a monster cam.

ForceFed HP

while there is not real standard for stages on cylinder heads(what one shop calls a stage 1 some call a stage 2) the head you are refering to sounds like what I would call a stage 3 and for us a stage 3 is suited towards 4" bores or larger.