Compression Test
Thread Starter
Member
Joined: Aug 2003
Posts: 344
Likes: 3
From: Panama City, Fl
Car: '89 Formula, '97 Z28, '88 Formula 350
Engine: 305 TBI(LO3)
Transmission: TH700R4(MD8)
Compression Test
My car hasn't run in about two years now. It had a cracked flywheel, bad fuel pump and smoked real bad(only when you set idling, like at a long red light). Going down the road it didnt smoke even when you stomped it to the floor. Well over the past month I've put a new torque converter, flywheel and valve seals( the umbrella seals & O-rings.
Today I did a compresion. The motor was cold(shoulden't it be warm?), the throttle was wide open and all the plugs were out. It didn't look good to me. #1~100, #2~85, #3~50, #4~90, #5~60, #6~105, #7~130 and #8~45. The shop manuel calls for 100-150psi. Do ya think it would've made any difference if it was warm? Is this real bad? Please give me some insight on this. Thanks, Bobby
Today I did a compresion. The motor was cold(shoulden't it be warm?), the throttle was wide open and all the plugs were out. It didn't look good to me. #1~100, #2~85, #3~50, #4~90, #5~60, #6~105, #7~130 and #8~45. The shop manuel calls for 100-150psi. Do ya think it would've made any difference if it was warm? Is this real bad? Please give me some insight on this. Thanks, Bobby
Senior Member
Joined: Jan 2002
Posts: 812
Likes: 0
From: Red Deer, Canada
Car: 89 Shortbox
Engine: 350 Vortec
Transmission: 700r4
You need oil in your rings and on your walls to get a seal. Do a test after the motor has ran. I try to do it on warm motors (not hot).
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