Head Gasket Question

Alan Warman · 11-28-2007, 12:38 AM

How much crush should a head gasket have.I am using a Fel-Pro head gasket for my Oldsmobile.The book says it should be .040 but when I measured it I come up with .045.So I thought when I torqued the head down to spec it would be .040.But it wasn't, it was .045. So I checked the bolt length, and thread engagement.I chased all the threads with a bottoming tap and reassembled and checked again, the same thing .045.So what am I doing wrong.

Jeff Lee · 11-28-2007, 01:47 AM

Your probably not doing anything wrong. You just have a head gasket that crushes to .045
So you either have a .005" cusion and you go to sleep knowing teardown will be a breaze or you find another brand of gasket. Often times it takes finding a set of OEM gaskets.
Don't forget, your deck height can be adjusted to the gasket thickness (as it deviates from NHRA specs).

11-28-2007, 12:38 AM	#1
Alan Warman Member Join Date: May 2002 Location: San Angelo Tx Posts: 231 Likes: 0 Liked 0 Times in 0 Posts	Head Gasket Question How much crush should a head gasket have.I am using a Fel-Pro head gasket for my Oldsmobile.The book says it should be .040 but when I measured it I come up with .045.So I thought when I torqued the head down to spec it would be .040.But it wasn't, it was .045. So I checked the bolt length, and thread engagement.I chased all the threads with a bottoming tap and reassembled and checked again, the same thing .045.So what am I doing wrong. __________________ Alan Warman STK 4107

11-28-2007, 01:47 AM	#2
Jeff Lee VIP Member Join Date: Jul 2007 Location: Anthem, Arizona Posts: 2,766 Likes: 0 Liked 3 Times in 3 Posts	Re: Head Gasket Question Your probably not doing anything wrong. You just have a head gasket that crushes to .045 So you either have a .005" cusion and you go to sleep knowing teardown will be a breaze or you find another brand of gasket. Often times it takes finding a set of OEM gaskets. Don't forget, your deck height can be adjusted to the gasket thickness (as it deviates from NHRA specs). __________________ Jeff Lee 7494 D/S '70 AMX