someone told me that my stock lt1 alum head wont get me to the 8:5:1 after my forged engine build i was told i would need to go to a larger CC head since the lt1 stock 58cc wouldnt be enough to get me to my desired comp ratio my question is the only head that looks as if it will do anything and change up drastically would be AFR's 210's with a 66cc head would this get me to the desired 8:5:1 ratio with the correct dish piston. i noticed that they are $2500 for a pair is there any other alternative as far as other heads with larger CC's how about getting a older style SBC head and converting it who does this as i had heard of it before.


any help would be great.

 

Doubt your stock one is 58 - They are usually 53-54 only way to know for sure is to check it. Match everything together.

Find one of the online compression calculators to figure out what cc you need for your goal.
http://www.csgnetwork.com/compcalc.html

Mine
4.030 bore
3.5 stroke
.039 gasket @ 4.125 gasket bore
.005 in the hole - jsut barely
-24cc piston
managed to get stock heads opened up to 59.5cc - took quite a bit of work

So that puts me @ 8.86. Which I think is fine unless you need insane amounts of boost. But start going low on compression and 5psi will feel like a turd. I am running 10psi right now and not real happy yet.

Trickflow has some lt1 castings that dont really flow much better out of the box but are like 72cc I think.

Any head can be modified to an extent though.

 

I'm not 100% sure on this but the stock iron LT1 head has 64cc (can anyone verify this?). If you don't mind some extra weight, those are cheap.

 

would love to a link of the trick flows which have 72CC chambers cause i cannot find anything higher then a 66cc head made by AFR which are way to costly...

as far as the iron heads i think that is where i pulled the 58cc number from the iron heads but i could be wrong as i have seen them debated between 54-58cc's i have like 3 sets of these for sure dont mind the weight just want to drop CR.

 

I know the aluminum heads are 54.5 with spark plug, and the impala's compression ratio is the same but with a smaller head gasket so the heads must be around 58-60cc.

 

trickflow. I dont know if there 72cc's but with some work you ll get your motor at 8.5.1.. AFR's are nice but you can get trickflows for cheaper and i think the only afr's that perform better are the 220cc+ models.
Check out AI and LE, they both have sets of those heads flowing 300cfm's at 650. But your not going to get away from that 2500 dollar price. That is going to chase down all heads that perform at that level. Bite the bullet.

 

The trickflows are 62, I have them. You can work them to get a bigger cc chamber, I left mine alone until the time when I send them to AI.

 

so is anyone postive what CC the iron heads are? it would be nice insurance for the fact that they won't heat up and warp like our heads. weight really isn't a issue since i have deleted AIR,HAVC,EGR,PS,ABS,cruise control,front sway bar,crash bar. but then added a huge FMIC

can iron heads be ported?

 

Cast iron heads can be ported, but it is a bitch to do so. Consequently more expensive.

Rich

 

Rich are the CC's bigger on the iron heads?

 

I am not sure. I never measured any, but I have been told they are 64cc.

Rich

 

what would you do,port a set of stock heads. or spend alittle for the iron heads since they are cheap and run them? i just sold a set of stock heads with hardware unported for a good price. thought about maybe going trickflow? sorry for the thread jumping......

 

Well I'm a little biased, but I would say go trickflow. They have more potential based on the thicker deck, larger cc chamber, and ability to be ported more. If you ever need to lower the cr even more, they can be opened up. AI is making killer power with these on stroker motors, should be awesome when ported on a boosted motor. I'm not expecting to be impressed with them since I'm running them out of the box, but when I get money down the road to port them, it will definitely be worth it.

 

I figure TF's should out perform stock no matter what,since like you said more meat on them..

 

Yea they will be a better head, but out of the box they only flow like 240 or 250, not great by any means, but definitely better than stock. A stock ported head will make a good deal more power than an out of the box trickflow, but when the TF is ported