March 20, 201114 yr comment_349984 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. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-349984 Share on other sites More sharing options...
March 20, 201114 yr comment_349985 Dang, you beat me again, Jeff. :lick: Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-349985 Share on other sites More sharing options...
March 20, 201114 yr comment_349987 Dang, you beat me again, Jeff. :lick: That's twice in a few days. You need quicker fingers. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-349987 Share on other sites More sharing options...
March 20, 201114 yr comment_349990 That's twice in a few days. You need quicker fingers. I'm depressed now. I think I'll go hop in the Z and go for some ice cream! Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-349990 Share on other sites More sharing options...
March 20, 201114 yr comment_349991 Now you're playing dirty. You KNOW my Z is still hibernating. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-349991 Share on other sites More sharing options...
March 20, 201114 yr comment_349993 Now you're playing dirty. You KNOW my Z is still hibernating. Yes, I do. :bandit: Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-349993 Share on other sites More sharing options...
March 20, 201114 yr Author comment_350002 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. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-350002 Share on other sites More sharing options...
March 20, 201114 yr comment_350014 I had a setup very much identical to that on my current '78 and did not hit. Either the timing is off a few teeth, or the head has been milled. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-350014 Share on other sites More sharing options...
March 20, 201114 yr comment_350018 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. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-350018 Share on other sites More sharing options...
March 20, 201114 yr comment_350019 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. Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-350019 Share on other sites More sharing options...
March 20, 201114 yr Author comment_350079 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? Link to comment https://www.classiczcars.com/forums/topic/38956-its-always-what-you-least-expect/?&page=2#findComment-350079 Share on other sites More sharing options...
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