Wondering what the maximum compression could be and still get away with 93 octane pump gas? I haven't ordered my heads yet.....and as you all know....the combustion chamber of a head plays a key role in your engines compression...... Thanks

 

yea, i know im not answering your question, but for me to feel like i know what im talking about, ill give my 2cents. ive heard of like 11.5 w/93octane, but not anymore than that. what is your application?

 

stock lower end...mini ram, Canfield 195s (trying to figure out what cc to order) 1 3/4 Hooker LT, cam in the 224° range.... I need the comp. to keep the cam happy......but want to avoid turbo blue if possible.

 

To get away with 11 to 1 on pump gas you will need a cam that reduces cylinder pressure at low speeds. These cams normally have very tight lobe separation angles (around 110 or lower) and that is something that ecm loop motors don't like. You will be sending fuel into the exhaust and the o2 sensor will not allow the motor to go into closed loop.

Shoot for a cranking compression around 200 psi. I know that's kind of hard to design for but...

With a cam of 224 I would keep compression very close to 10 to 1

[This message has been edited by jcb999 (edited November 09, 2000).]