general23cmp

iTrader: (1)

I am building a 427 LS3 stroker with aftermarket flat top pistons with valve reliefs. I plan on checking my piston/valve clearance upon building, but it would be nice to have an idea of the general limitations that I could expect. How much lift is generally too much? I know it depends on duration, but I would like a general answer. If you really need duration numbers, lets say a maximum of 245 for intake and 260 for exhaust at 0.050".

AM I pushing my luck at 0.650", 0.700", etc. of valve lift?

general23cmp

iTrader: (1)

C'mon guys....how about some success stories?

For example, I used XXXXX cam with L92's and flat tops with 4cc valve reliefs with no problems.

STEEPSS

iTrader: (30)

It's not just about lift, you know. It has to do with the valve events. I had to flycut my pistons, and I'm only running a 228/230 .588/.592 on a 112. 62cc chambers. Stock pistons. I checked mine, and I only had .016 on the intake side. Went ahead and opened it up to .080 (recommended).

I would contact one of the sponsors. TSP for example. Very knowledgeable.

SweetS10V8

iTrader: (4)

Lift has nothing to do with it. Do you know where your piston is at max lift??? It has to do with valve event timing and how aggresive the lobes are.

My heads were milled .030" and I didnt flycut. I also have OEM flat tops without valve reliefs. My story really doesnt match well with yours because your pistons will give you a lot of PTV.

I tried a 223/231 .610/.617 113 Comp LSR cam and had .040" intake PTV

I ended up with a 219/235 .607/.621 113 Comp LSR cam with .075" intake PTV.

Are your heads ported??

I would keep the cam around 238/248ish. Run .675" lift if you want, just make sure you have a good valvetrain and it helps if your heads still flow good air above .600 lift.