Pistons?

[geezer101]

Your CR is going to drop to 9:1 or lower depending on the piston type. To be honest I think you're chasing your tail by not going twin cam. You'll get over some hurdles but run into others - you'll be able to get the right pistons, you will easily be able to achieve a CR of greater than 10:1 and the twin cam head will be a major improvement in HP and torque. You'll need to figure out the exhaust manifold and decide how to tackle the intake side of the engine but this is all stuff that has been done before.

[dash]

Doesn't $50 dohc junkyard head give you high compression when bolted onto a stock 2.4 block ?
Could be another route
Or just go nutz; http://forums.austarion.com/viewtopic.php?f=3&t=16193