what would the advantage be of having 72cc heads over 64cc heads. i know that the compression ratio will change but i am building a engine and could buy different pistons. will one give me more power than the other or does it not really matter? Thanks

------------------
Twells

1992 R.S. 25th Anniversary
* Borla
* Open Element
* Hypertech Chip
* Smog pump delete

Thats all for now!!

 

There isnt one, especially if the smaller chamber is designed to promote swirl. All the 70+ cc heads I have seen have nothing to promote swirl.

 

anyone else? ttt

------------------
Twells

1992 R.S. 25th Anniversary
* Borla
* Open Element
* Hypertech Chip
* Smog pump delete

Thats all for now!!

 

anyone else? ttt

also, is there a better flowing aftermarket head than the fastburn heads, for about the same price?THanks

------------------
Twells

1992 R.S. 25th Anniversary
* Borla
* Open Element
* Hypertech Chip
* Smog pump delete

Thats all for now!!

 

If your not going with a blower...... get a 64 cc head!!! I have a set of canfield alluminum 65 cc heads, best heads ever made!!!! i say get a pair..... 200 cc intake, 2.05/1.60 valves

Cody

------------------
Wieand blown 87 camaro

 

Combustion chamber size is only one part of head design. 305 heads are about 58cc but you wouldn't want them on anything larger than a 305 since the intake runners can't flow enough air to feed a larger engine.

As long as you use flat top pistons, you can use 64 or 76cc heads to get the compression ratio you want. A higher compression ratio will require at least 92 octane to keep detonation down since you'll probably be over 9:1 compression with 64cc heads. If the block is zero decked then the ratio could go even higher.

Buy pistons that will give around 9:1 to 9.5:1 with a larger chamber head such as 76cc. The larger chambers will unshroud the valves better than small chamber heads. You'll still need premium gas but will make more power.

If you decide on aluminum heads then you could go in the 10-10.5:1 range for compression. It all depends on your complete engine setup if you'll get detonation or not.

------------------
Follow my racing progress on Stephen's racing page
and check out the race car

87 IROC-Z SuperPro ET Bracket Race Car
461 naturally aspirated Big Block

Best ET on a time slip: 11.242 altitude corrected to 10.89
Best MPH on a time slip: 121.52 altitude corrected to 125.89
Altitude corrected rear wheel HP: 497.9
Best 60 foot: 1.546

Racing at 3500 feet elevation but most race days it's over 5000 feet density altitude!
Member of the Calgary Drag Racing Association

87 IROC bracket car, 91 454SS daily driver, 95 Homebuilt Harley