Jake_305

About too pull the trigger on the stage 1 porting of my 243 heads, kooks longtubes and a 228R on a 114. Just wondering how much to mill off the heads. The car is a 2005 ctsv peak hp is not the goal a good daily driver is. The stock chambers are 64cc i believe. Would it hurt to do 63cc?

wannafbody

iTrader: (2)

What's the point? I'd leave them stock 64cc.

00pooterSS

iTrader: (40)

I would definitely mill them if you're considering it, but only milling to drop 1 cc is a waste of time and money.

I'd go down to 58 cc if possible without valve clearance issues, or at least down to 60 cc

Ask the cam manufacturer to be sure but a 228 cam should have plenty of clearance even with milled heads. And as always measure and make sure once you get it together. You could do the cam and measure and see exactly how far you can mill, then mill.

G Atsma

I'd be surprised if all chambers were within a cc. But yeah milling for a cc? A cleanup skim will take more than that.

qweedqwag

Put them on, that cam is amazing, Loved it in my LS1 bird.

Utinator

I'm running a similar cam (224/228-114) with .600 lift. I milled my 317 heads .030, and don't have any clearance issues. The .030 made the chambers 6cc smaller. With 243 heads (about 65cc), I would mill them about .015-.020. That should put the chambers at 62-60cc. For an LS1, that would put the compression around 10.8-11.0. What engine are you working with?

Utinator

Just to give you an idea of what it will sound like:

Before:

After:

G Atsma

That's a nice sounding idle! Still "muscular" without being too lopey.

BullyDawg

iTrader: (1)

I'm running that exact cam with the same LSA. I have PRC 2.5 243 heads milled .020 and running a .040 Cometic Gasket

Sales3@Texas-Speed

iTrader: (2)

If we're doing the head porting, then going with the stage 1 porting process (stock valves) we can mill up to .035 off. If you choose to go with the 2.5 process (larger stainless valves) we can mill up to .030 off and still keep safe PTV clearance. Be aware that this is what WE can mill off. The reason I say that is because when we do our valve job we sink the valves a little to give us extra clearance.

Lonnie