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Moto

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Another thought - how much much did they mill off of the head you took off? The head thickness (face to cam cover surface) should be ~108mm (4.25"). If it is much less than that, it would bring the valves down as well.

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Thanks guys, yer'all quite the awesome group.

Regarding the flat top pistons kissing the valves, the new head I'm running, it has a Schnider Cam 460 lift 270 duration. The head was installed on an F54 block, and ran with stock valve timing. Tomorrow (if there is no rain) I'm going to install the head and check the valve to piston clearance. Now for what might be a dumb question.

When the piston is at TDC on the exhaust stroke, is/should the exhaust valve be all the way opened, or already started closing? The reason I asked is I set the cam so that one of the exhaust valves was "all the way" opened, then put the same piston at TDC, then set my old gasket into place. I placed the head down on top of the block and the valve was just barely touching the piston. Now if at TDC (exhaust stroke) if the valve has already begun to close, my guess is it would not hit.

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Thanks guys, yer'all quite the awesome group.

Regarding the flat top pistons kissing the valves, the new head I'm running, it has a Schnider Cam 460 lift 270 duration. The head was installed on an F54 block, and ran with stock valve timing. Tomorrow (if there is no rain) I'm going to install the head and check the valve to piston clearance. Now for what might be a dumb question.

When the piston is at TDC on the exhaust stroke, is/should the exhaust valve be all the way opened, or already started closing? The reason I asked is I set the cam so that one of the exhaust valves was "all the way" opened, then put the same piston at TDC, then set my old gasket into place. I placed the head down on top of the block and the valve was just barely touching the piston. Now if at TDC (exhaust stroke) if the valve has already begun to close, my guess is it would not hit.

You set the exhaust valve all the way open at TDC and your engine ran? That's the obvious reason behind the valve-to-piston contact. TDC is the overlap period of the intake opening and exhaust closing, and neither should be completely open at that point. Your cam timing is way off and you need to set it according to the cam card provided.

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Thanks guys, yer'all quite the awesome group.

Regarding the flat top pistons kissing the valves, the new head I'm running, it has a Schnider Cam 460 lift 270 duration. The head was installed on an F54 block, and ran with stock valve timing. Tomorrow (if there is no rain) I'm going to install the head and check the valve to piston clearance. Now for what might be a dumb question.

When the piston is at TDC on the exhaust stroke, is/should the exhaust valve be all the way opened, or already started closing? The reason I asked is I set the cam so that one of the exhaust valves was "all the way" opened, then put the same piston at TDC, then set my old gasket into place. I placed the head down on top of the block and the valve was just barely touching the piston. Now if at TDC (exhaust stroke) if the valve has already begun to close, my guess is it would not hit.

The valve should be closing and the intake should be opening. I'd need more cam specs to know how much close and open the valves would be. Jeff would be able to help you out more since he has had a similar setup. Do you see signs on the head it was milled you really since you have it off need to check this, because it will be key in fixing the problem.

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You set the exhaust valve all the way open at TDC and your engine ran? That's the obvious reason behind the valve-to-piston contact. TDC is the overlap period of the intake opening and exhaust closing, and neither should be completely open at that point. Your cam timing is way off and you need to set it according to the cam card provided.

No I did not install it that way. I just set the head on top of the block to get a basic idea of how close the valves were to the pistons. It's pouring down rain here in So Cal, so I'll install the new head with correct valve timing when the rain let's up.

On a negative note after crasling around under the car it's about ready to break in half due to the amount of body rot. The floor pans and rails are are crumbling away. Any sugestions on who makes the best replacements?

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