Stone0fFire

im planning on getting a 224 cam or so,
and want to know which heads to get with it.
i heard if i raise the CR from 10.25 to 10.75,
the car will have more power and pass smog more easily.

all i know is i should get hand-worked ls6 heads, right?
but 5.3L? 5.7L?
what can i get away with using 91 oct?
how will this affect my gas mileage?

Linear Velocity

iTrader: (1)

Heads and compression will not affect smog. The LSA on your cam and your header/exhaust setup will. If you get a 224/224 cam you will need to get 114-116 lsa for it to pass smog in CA. Unmilled 5.3 heads will give you a 10.8 to 11:1 compression ratio depending on what kind of head gasket you use. Either will be fine running 91 octane (My Stage 1 5.7 heads are milled .030 and will give me an 11:1 CR) Gas mileage will be mildy affected, but more so if you have a lead foot If you want to stay 100% smog legal in Cali you will need to stay with shortie headers and cats. If you get long tubes with cats you can pass the sniffer, but will fail the visual. Orf course soome shops will overlook the visual for a fee As far as heads, if you're looking for a stage 2 port job 5.3's would be the cheapest and flow pretty well. LS6 heads would flow better but I don't think they are worth the extra $1,000 for the 15rwhp or so. I would call Ricahrd at West Coast Cylinder Heads, they are a sponsor on this board and are local (Reseda) they do great work and have great prices. Good luck. ~Tony

M6HuggerSS

well im in CA (san diego) and just orderd my H/C combo.....this is what i chose...

well i finally did it... layed down the green backs for a decent head and cam combo from GEN 3 PERFORMANCE!

i should have it installed within 2 months so ill keep you all updated...

i havent recived my itemized list but im pretty sure on most of it...

-5 axis fully CNC'd and hand polished stage 2 5.7 heads
-FERRA 2.02/1.60 valves
-COMP 26918 springs
-Titainium retainers
-new seats and seals...
-flow numbers to come
-milled to a 10.8:1 CR

-MANLEY hardend pushrods

-COMP 222/224 .566/.568 114

-GM bolt and gasket set

-and maybe an LS6 intake???

i cant wait! im so stoked... then a fuul tune when its all done!
im hoping for 400rwhp! well see?

like others will tell you....the 5.3 will be the cheaper head...10.8:1 CR (you dont want any higher than that) and they flow well! 5.7 can be milled to get the same CR...around same priced and flow around the same...but have a bigger CC. and LS6 will be big$$ and will out flow them all but with a small CA cam you may not take full advantage of them.....thats why im just getting a good set of stage 2 5.7.....milled!
and polished heads look way nicer than just a CNC head! and you can even do that yourself! have fun let me know what you decide on!

Stone0fFire

good point,
it is a relatively small cam,
224/224.. 114.. i forget the lift.
anyway,
why do you say i would want no higher than 10.8:1 CR?

and if you can mill 5.7 heads to give the CR of 5.3,
what would then be the difference?
the flow rate from the valves?

what should i do if later on i decide to run a 150 shot?
i am more concerned with a low low ET than with a couple ponies on paper.


thanks for all the replies

M6HuggerSS

for what i can remember? the 5.3 has a smaller CC. so with no milling you get a bigger CR! that means you can run a cam with more lift with PVC problems! where as if you mill a 5.7 head to get a 10.8:1 CR your loosing some PVC and you cant run a ton of lift!

but for my baby cam thats not an issue. as far as CR goes i heard that 11:1 is to much for CA gas and the traffic and the summers....i was told that an increase to 10.8:1 will make good power and keep the motor safe!

Linear Velocity

iTrader: (1)

I had 11.5:1 CR with my heads/cam need had a problem running 91 octane in CA, even in the summer. He'll be fine with an 11:1 CR.

M6HuggerSS

im sure there are people that have had no problems... but for me id rather be safe than sorry! but its up to the owner!

Stone0fFire

wow, 11.5:1!!!
11:1 sounds fine, then.
but..
what if i plan to run a 150 shot on 91oct?
what CR would you guys go with?

Stone0fFire

224/224 114lsa cam,
150 shot maybe later on..

which CR for 91 oct?
11:1 okay?

i plan to get at least the cam soon

Phate

iTrader: (2)

I have a set of ported '98 5.7 heads that were originally ARE Stage II and then re-ported by Richard at WCCH for sale.

They have had the notch in the head welded up so that they can be run with the MLS or Cometic gastkest, 2.05/1.6 valves, the springs/locks/retainers only have about 300 miles on them since Richard went through them.

These were the heads were on my car for about 300 miles and then I had TH-400 trouble and a little too much blow-by and ended up pulling the motor and trans together. Since I had already purchased another long block these have been sitting.

PM me if you are interested, I'm going to let them go for a very reasonable price.

Thanks,

Scott