Raising compression in sohc ej25, mill heads?

[asimmons04]

would continue in last thread, but yeah. maybe i will catch some eyes with this one.

03 Baja, SOHC EJ25.

Ok, gaskets are leaking oil and coolant (outside). So, if I have to go pulling the heads, I was thinking I would get the heads milled a little and gain some compression. I have no issue running higher octane fuel, I'm going for a little more power. I'm running a CAI with cone style filter, and better exhaust from cat back. I had some questions though. Bottom end is very tight, truck runs great. 160k miles of good synthetic oil always changed at 3-5k miles.

How far can I have it safely milled to wind up at about 10-11.1 compression?

Will this interfere with bolting on the intake?

How much to they usually charge ya'll at machine shops just to mill these heads?

Plan to run FelPro's replacement MLS gaskets, if that helps. Thanks guys.

I have a money limit or I'd just throw in HC pistons and rings, cams, etc.