I was wondering if anyone has put AP1 pistons into a AP2 motor. The AP1s have alittle more dome then the AP2s and I was just wondering if its been done before and or even possible? thanks

 

The USDM AP1 pistons will increase your CR to about 12:1. The JDM AP1 pistons will increase it to more like 12.5:1.

You will need an EMS and a good tune but it can and has been done.

 

so they cant be just installed with a vafc tune?

 

It's not the AFR that would need adjusting, which is what the VAFC does. It is the timing.

 

so could an emanage ultimate do it then because that can change the timing?

 

Yes it could

and Vmanage could manage VTC

 

Thanks for the reply's. Is it worth the time to do the swap?

 

likely not.

it would be a lot easier to throw one of the thinner headgaskets on for similar gains.

Also, bumping up the compression really isn't going to gain a lot of power. You're looking at a complete engine rebuild to gain maybe 10hp at the most if you're lucky. There are way better ways to spend your money.

 

HG is only worth about 0.3 points of compression.