Compressions Test ?'s
Thread Starter
12 Second Club
iTrader: (49)
Joined: May 2006
Posts: 966
Likes: 0
From: College Station, Texas
Compressions Test ?'s Hey guys I just have a few questions about running a compression test. I just read an article from motor age and here is how I plan on testing my compression. Let me know if this will work:
1. Run engine for 10 minutes to allow it be warm.
2. Disconnect coil pack harnesses from each side.
3. One at a time, pull the spark plugs and thread the compression gauge into the head where the plug was just removed. (Basically from what I understand, while I check the compression on one cylinder, the other 7 plugs are still threaded into the heads).
4. In order to check the compression for each cylinder, simply turn over the engine for 5 seconds or a little more.
5. Reconnect harnesses and grab a beer.
I just turned 100k on my odometer and I plan on running a leakdown test if any of my numbers on the compression test turn up dissappointing. The compression test will be me answer on whether I will run a heads and cam setup on this shortblock or simply make it a boltons car until the stock shortblock blows and then I can run my plans on a forged 346 h/c motor. Let me know because the results are important and I want to make sure I'm testing correctly. Also, any reccommendations on where I should get a compression gauge?
Thanks in advance,
Josh
1. Run engine for 10 minutes to allow it be warm.
2. Disconnect coil pack harnesses from each side.
3. One at a time, pull the spark plugs and thread the compression gauge into the head where the plug was just removed. (Basically from what I understand, while I check the compression on one cylinder, the other 7 plugs are still threaded into the heads).
4. In order to check the compression for each cylinder, simply turn over the engine for 5 seconds or a little more.
5. Reconnect harnesses and grab a beer.
I just turned 100k on my odometer and I plan on running a leakdown test if any of my numbers on the compression test turn up dissappointing. The compression test will be me answer on whether I will run a heads and cam setup on this shortblock or simply make it a boltons car until the stock shortblock blows and then I can run my plans on a forged 346 h/c motor. Let me know because the results are important and I want to make sure I'm testing correctly. Also, any reccommendations on where I should get a compression gauge?
Thanks in advance,
Josh
Your supposed to let the engine get warm
Pull out all of the spark plugs. (easier on the starter and will get a more accurate reading)
Block the throttle so it is wide open throttle.
screw your adapter in one hole at a time.
Then crank engine about 4 revolutions.
If you get low readings then put some oil in the cylinders with a straw and then re preform the test. If the number go back up then its you rings that are leaking. If not then preform a leak down test and go from their. let me know if you have any questions i have done this like 20 times, just not on a f-body, because they are a pain in the *** to get to the plugs. Just hope you don't have to do a leak down, because then you looking at getting more involved.
Pull out all of the spark plugs. (easier on the starter and will get a more accurate reading)
Block the throttle so it is wide open throttle.
screw your adapter in one hole at a time.
Then crank engine about 4 revolutions.
If you get low readings then put some oil in the cylinders with a straw and then re preform the test. If the number go back up then its you rings that are leaking. If not then preform a leak down test and go from their. let me know if you have any questions i have done this like 20 times, just not on a f-body, because they are a pain in the *** to get to the plugs. Just hope you don't have to do a leak down, because then you looking at getting more involved.
Last edited by Jditlfm; Apr 2, 2007 at 06:40 AM.
Thread Starter
12 Second Club
iTrader: (49)
Joined: May 2006
Posts: 966
Likes: 0
From: College Station, Texas
I would try leakdown right off the bat but my compressor is so shitty that it would be constantly running building air pressure and on top of that the coupler I have is kind of leaky. I wouldn't be able to hear the leak anyways basically.
Josh
Josh
