LilJayV10

iTrader: (39)

and if you are going to have to fly cut anyway, i'd mill the heads as much as possible. You need more compression with that cam IMO anyway.

267kbird

I'm going to fly cut. I'm going to have them mill them another .20 and I'm going to .40 gasket. I'm just wondering if I need to just bring piston up to where it will hit the cutter with headgasket on or off? Or do I need to rotate motor up to TDC as I'm cutting piston? I have a set of new gm MLS gaskets. Should I use these when cutting? There bigger than .40 cosmetic im going to run. I'm just wondering how to get my reliefs in the right spot .

tug686spd

iTrader: (11)

I always just bolt the head straight to block with no gasket. Have the piston slightly below deck surface when head is put on the rotate crank until piston hits head, The grease is a good idea for catching the grindings but is a pain to clean up. I use regular old white foaming shaving cream. Cleans up real easy

Che70velle

iTrader: (6)

I use steel valve spring shins to replicate the gasket thickness. In your case, use .040 shims. They are super cheap and you can get them easily. Buy 6 or 8 of them and place them on the deck surface where headbolts are. Run the headbolts down through the center hole of the shim. That way they can’t move. All you want to do here is snug the head down. Do not tighten the headbolts, simply hand snug. I set my pistons at tdc for cutting, and it has always worked well. I check with clay after first piston to make sure I’m cutting deep enough, but not too deep. Too deep and your throwing compression away and weakening the piston crown. Radial clearance is as important as depth, so when checking with clay, measure your radial clearance also. The cutters are made slightly oversize, for radial clearance numbers to be correct, but check anyway.

267kbird

OK thank you.

LilJayV10

iTrader: (39)

When you check PTV use a headgasket that you are going to use.

Don't check PTV at max lift, that isn't where you are going to run into issues. At max lift the piston is way down the cylinder. The more aggressive the lobe and lift, the valve is "chasing" the piston so to speak. So the faster you open the valve at a higher rate, you are going to have PTV issues when the piston is closer to the cylinder head. BTDC and ATDC.

Everyone does it different and I'm not saying my way is the right way or the best way.

Decide what head gasket you are going to use. Slap it on there, snug the head down, check PTV.

I check it 15 degrees BTDC, in 5 degree increments to 15 degrees ATDC.

Bring the cylinder up to TDC, tape the cylinder up. Install the cutter in the head and cut whatever you need.

64post

iTrader: (5)

Use a degree wheel and soft test springs to find the exact location in degrees where the piston is the closest to the valve and that is in overlap (one valve opening, one closing) usually 10* before to 10*after, the test spring allows you push down on the valve beyond what the rocker has moved the valve. Or you can use clay method. Either way fly cutting Hypereutectic pistons is a wrisky move, they’re brittle and not well if at all reinforced where you’ll be cutting the reliefs. Go forged.

267kbird

So I got my heads back with 2.02 and 1.57 valves I have the cutters. For that size. Has anyone used a old junk ls head to do it? Even with the stock xmaller valves on the old head? I'm assuming my cutters would stick out a little ?

267kbird

Well in the process of flying cut head on and off million times I scratched my head by the dowel holes. Anybody think it is something to worry about? Also one from the water jacket to the side.

LilJayV10

iTrader: (39)

It's fine, one it's not that bad and two there isn't anything over there that does any sealing.

267kbird

By the dowels? Or by the water jacket your saying?