Cranking compression reading

Lonnie Cox · 06-23-2013, 04:34 PM

76 camaro I/SA 350 40 over, cp pistons, Bullet cam, any idea what cranking compression we should have. Just would like to know.cam is in at 98
Thank You

GTX JOHN · 06-23-2013, 05:38 PM

MY 9.5 to one Mopar Small Blocks run approximately 160 lbs.

Lew Silverman · 06-23-2013, 05:48 PM

Lonnie,

The numbers may not tell you very much when you are looking for a "high" value. The compression test is a good way to tell if any one (or a number of) cylinders is having a mechanical problem. What you look for is a pattern where each of the cylinders is within 5 to 10 psi of the others.

It has been my experience that a "leak-down test" is a much better gauge of engine health and efficiency when done properly. The kit is not that expensive and only requires an air-compressor capable of 100 psi of pressure. Done on a regular basis, it is a much more accurate diagnostic tool.

Lew

06-23-2013, 04:34 PM	#1
Lonnie Cox Junior Member Join Date: May 2010 Posts: 88 Likes: 0 Liked 0 Times in 0 Posts	Cranking compression reading 76 camaro I/SA 350 40 over, cp pistons, Bullet cam, any idea what cranking compression we should have. Just would like to know.cam is in at 98 Thank You

06-23-2013, 05:38 PM	#2
GTX JOHN VIP Member Join Date: Jun 2009 Location: Boulder City, Nevada 89005 Posts: 2,733 Likes: 2,799 Liked 2,482 Times in 697 Posts	Re: Cranking compression reading MY 9.5 to one Mopar Small Blocks run approximately 160 lbs.

06-23-2013, 05:48 PM	#3
Lew Silverman VIP Member Join Date: Mar 2010 Location: Newport News, VA Posts: 1,435 Likes: 371 Liked 129 Times in 59 Posts	Re: Cranking compression reading Lonnie, The numbers may not tell you very much when you are looking for a "high" value. The compression test is a good way to tell if any one (or a number of) cylinders is having a mechanical problem. What you look for is a pattern where each of the cylinders is within 5 to 10 psi of the others. It has been my experience that a "leak-down test" is a much better gauge of engine health and efficiency when done properly. The kit is not that expensive and only requires an air-compressor capable of 100 psi of pressure. Done on a regular basis, it is a much more accurate diagnostic tool. Lew __________________ Lew Silverman #2070 "The Wagon Master" N/SA