GreatWhiteHype01

Will 243 heads from the C5 Z06 mount on the 3.9" bore LS1 found in the 98-02 Camaro/Firebird? If so is there a substantial gain found in them over the 241 LS1 heads? I am looking at a set that are brand new LS6 heads (243 casting), Stage 1 ported by Livernois Motorsports. Assembled with stock LS6 valves, retainers and springs, stock chamber size. Any suggestions? Thanks. -Tom.

12secSS

iTrader: (30)

Those heads were first introduced on 2001 LS6 engines, so yeah they will work on an LS1 (3.89" bore). You should see about 10-20 hp increase with stock 243 heads over 241 heads. With ported ones, you can see as much as 25-30.

DANOZ28

iTrader: (1)

i think 98 heads have a different bolt pattern. but 99-2002 should be fine. the positive with actual vette heads is they come with light weight sodium filled valves (not sure if both exhaust & intake). however right now one of our sponsors is running a special on ls6 heads (w steel valves). i believe stock 241 heads flow about 245 cfm, stock ls6 flow about 265. and ported heads flow over 300 plus.

DANOZ28

iTrader: (1)

prt 2 i mistake i felt i made was not upgrading the ls6 standard springs to say patriot gold (good to 650 lift cams) if nothing else its added insurance.

Bad Blue WS6

iTrader: (41)

the different bolt pattern is the valve covers only.

radkon

iTrader: (2)

This may help:

LivernoisMotorsports

iTrader: (1)

The heads will bolt onto any LS1 engine, however as others have mentioned the '98 cars will require different valve covers and coil packs.

Regards,

Rick LeBlanc
Livernois Motorsports

Beaflag VonRathburg

iTrader: (176)

Finally I'm going to save that graph for future newbie questions.

TARZAN

iTrader: (12)

Yes, they'll fit, and with a tune, they should provide noticeable gains.

-Will

Chucks1911

Very helpful chart radkon. Thanks for posting it.

Jray67

The hollow stem valves only cam in a few select years. 02-04 I believe, but don't hold me to those years. The recent 243 heads have solid valves. I have a set of 243 Stage I's from Livernois and they have solid stock LS6 valves.

Jray67

Livernois is a great company with great customer service. I talk to Mike there whenever I call. He answers all my questions and he's as nice as can be. I highly suggest them. You won't be disappointed.

radkon

iTrader: (2)

You're right, the hollow stem valves are only in the LS6 Z06 package. The 243's in the GTO and later heads are solid.

I don't remember where I found that chart but its very helpful!

quiet_storm98

iTrader: (48)

stock heads dont flow that well...more like low 200's to 220 or so cfm

Thorny

iTrader: (14)

It looks like the one from GMPP's performance catalog. I believe they have the flow numbers for thier different heads on there as well. The website that I know its on isn't a sponser here, so I won't post a link,but it should be available elsewhere too.

Dokken

Thanks for sharing this info