Intake Valve to Piston clearance

[Trev]

Hi guys

350 Chev
Flat Top KB pistons
Trick flow twisted wedge heads
Hyd Cam

We took 40 thou of the heads to boost compression up to 12:1
Checked the Valve to piston clearance and ist down to about 50 thou

Any of you guys ever ran this close without problems

I would like to run this close as the intake valve position on the TF / TW heads puts the fly cut right out at the edge of the piston and im not sure if that would be ok.

Any thoughts

Trev

[CNC BLOCKS]

We have been down to .040 on the intake valve with no problems.

[highVE]

I have also ran as close as .050" int before w/no problems, so long as you keep the rev limiter correct and don't go to valve float. or you could (worse case) retard the cams int centerline 1 or2 degrees, that will give you more intake pv cl., however it will tighten up your exh. so be carefull

[Adger Smith]

That material you are using for pistons seems to grow more than others when heated. I would rethink you clearance. I have run as tight as .040, but with other piston brands that are made of different alloys.

[Wolfplace]

.050 on the intake is not an issue even with valve float. You ain't gonna float the valve opening it & it is no where near the piston closing.
As for flycutting those I wouldn't, they are prone to cracking especially at the intake notch because the rings are so high.
I personally wouldn't be using that piston in a 12.0 engine anyway. They are very intolerant of detonation,,
Also, while on the subject of those pistons, in my opinion you do not want to use the 6" rod stroker ones that have that cute little pin that keeps the lower oil rail from turning.
I personally know of four engines in which one or more of those have come out which will tend to ruin your day.
Notice on their new forged piston they went to a support rail like everyone else,,

[crazycuda]

guys correct me if im wrong but I always thought you needed to run more clearance on the exhaust valve then the intake. Also if you only have .040 valve clearance with 0 lash then add the lash to the .040 (say .020 lash) then you really have .060 clearance.