Im doing my H22 buildup with Type S pistions, 0.02 mill, thin head gasket and flat valves, which I calculated would bring compression to approx 12.1:1.

The highest octane pump gas that we have is 94, should I hold back to lower compression just to be safe?

 

94 octane will be fine for normal driving. Just tune on the conservative side (Slightly rich with non agressive timing).

 

I think with a good tune, you'll be safe.

 

Tune it and you should be fine.

 

Hey, I'm local to you and my Compression ratio is 12.6:1

I run 94 all day long and its ok, just don't rag on it if you're running straight up 94, a lil race gas always help

 

I have 12:1 and I use 93, no problem. It's all in the tuning. You'll be fine on 93 octane, the AEM EMS is capable of the level of tuning needed to pull it off. I have an Uberdata tuning system myself.

 

12.6-1 on pump 93 and it's fine, little race gas once in a while, just get it tuned..


407-707 POWERLINE

 

I'm doing a similar build to yours with Jun cams and valvetrain, but with 91 octane gas. A number of people in SC are running higher than 12:1 compression on 91 octane pump gas. So you should be fine...for that matter me too!

 

I am running 12.25:1 on 91 oct. I am at 5000' elevation though...

Pirate

 

from 2300-3500 R's, part throttle, which is all that is really done at these R's, seems to be the most difficult to deal with the H22

 

more then fine...i run 12.7:1 on chevron 91....