The Ford Barn

Ken Henry · 08-12-2021, 09:18 AM

I had a set of EAB heads milled 0.015 - 0.020" to clean up the gasket surfaces and then painstaking relieved the dome areas to get a minimum clearance of 0.040" with the pistons. The combustion chamber volumes cylinders 1-8 are

68
70
69.5
67
66
69
70
68

How close should these be to each other?? I will have to grind a little out of the valve area on #5 since the clearance is borderline: 0.307/0.315 without a head gasket installed and my cam lift should be about 0.350. Others seem OK at 0.330-0.380 (without the gasket).

Here's my jig for measuring the piston clearance. For valve clearance, I installed the heads, valves and guides and measure how much I could move the valves up and down between the head and the seat, with a dial indicator on the valve stem tip.

93FE453B-D999-45C0-9447-774440828BC3 by kenhenry_06268, on Flickr

38F8D6AC-7705-4287-A7F1-267781AE84BB by kenhenry_06268, on Flickr

08-12-2021, 09:18 AM	#1
Ken Henry Senior Member Join Date: Jul 2010 Location: Rochester, NY Posts: 266	Combustion chamber volumes I had a set of EAB heads milled 0.015 - 0.020" to clean up the gasket surfaces and then painstaking relieved the dome areas to get a minimum clearance of 0.040" with the pistons. The combustion chamber volumes cylinders 1-8 are 68 70 69.5 67 66 69 70 68 How close should these be to each other?? I will have to grind a little out of the valve area on #5 since the clearance is borderline: 0.307/0.315 without a head gasket installed and my cam lift should be about 0.350. Others seem OK at 0.330-0.380 (without the gasket). Here's my jig for measuring the piston clearance. For valve clearance, I installed the heads, valves and guides and measure how much I could move the valves up and down between the head and the seat, with a dial indicator on the valve stem tip. 93FE453B-D999-45C0-9447-774440828BC3 by kenhenry_06268, on Flickr 38F8D6AC-7705-4287-A7F1-267781AE84BB by kenhenry_06268, on Flickr