Compression question
Thread Starter
Melting Slicks
Joined: May 2003
Posts: 2,387
Likes: 2
From: Meriden CT
Compression question
Hello all,
I was installing my new MSD ignition yesterday at my friends gas station. We pulled out the plug in cylinder 1 and put a compression gauge on. At TDC we read about 170psi. How does this convert to a normal compression reading (ie. 10.5:1) what unit is the normal reading in. Say I have 10 to 1 compression, what does that mean? Thanks for the help. Just curious.
Joe
I was installing my new MSD ignition yesterday at my friends gas station. We pulled out the plug in cylinder 1 and put a compression gauge on. At TDC we read about 170psi. How does this convert to a normal compression reading (ie. 10.5:1) what unit is the normal reading in. Say I have 10 to 1 compression, what does that mean? Thanks for the help. Just curious.
Joe
Safety Car
Joined: Aug 2001
Posts: 3,892
Likes: 13
From: Pettis Performance 565 with two stages of Nitrous Supply nitrous 1.082, 4.61 at 155, 7.17 at 192
Re: Compression question (JoeRags)
That is cranking compression and is not a direct indication of compression. You can not say due to the fact it is 170 cranking compression it is __ static compression. Cam timing, head flow, etc, etc play into cranking compression as well as actual static compression. The most you can say about a 170 psi cranking compression is that it should run fine on pump gas. When you get around 190 -200 psi the motor sometimes will need better fuel.
