Predator 212 help

RCJ

Member
I milled .080 off , that was to much. I would try .040 or shoot for a c/r of 10. That should work with 91 octane pump gas.
 

Curflo

Member
I cut .075 off the last 2 non hemis I did but both of those were around .030 in the hole an used a .010 head gasket
 

Johndougjr

Member
On the spark plug Autolite AR 3911 is the plug I like. AR3910X is a popular plug also.
AR 3910x is the plug they sent me, is the 11 a colder plug? I have a machinist Freind kinda, taking head to him 40 off 10 head gasket, what you think
On the spark plug Autolite AR 3911 is the plug I like. AR3910X is a popular plug also.
 

Johndougjr

Member
The hemi flat top is shorter than a non hemi. You will have to do a little research to find the right combination to get a flattop in it. I milled the head on my grandsons non hemi off road kart. Did not work good, had to run high octane fuel and the piston would break after a short time. I would sand off the short turn radius in the head , put it on the kart and run it. If you need more low end put more gear in it.
I did investigate and this is what I found.Wiseco has a flattop heavy duty piston that the man called a drop in, .490 wristpin but standard length so I’m going with that and the 40 off head. When you say high octane over 92
 

RCJ

Member
Wallace racing has a bunch of calculator for engine building including a c/r calculator. A 14cc head and flat top will get around 12.8
 
Top