Paulos
Active Member
- Joined
- May 7, 2018
- Messages
- 479
- Reaction score
- 210
- Points
- 43
- Location
- North Carolina
- Vehicle Year
- 1987 STX
- Make / Model
- Ranger
- Engine Type
- 2.9 V6
- Transmission
- Manual
- 2WD / 4WD
- 4WD
I just did a compression test on my 2.9 and came up with these numbers
#1- 175 psi
#2- 182 psi
#3- 182 psi
#4- 172 psi
#5- 180 psi
#6- 167 psi
I made sure that the engine was warmed up, power to the coil disconnected, throttle body wide open, and all plugs removed. I turned the engine over 9 or 10 times and checked each cylinder at least twice. It's around 60 degrees outside, a little less than 1000' elevation.
It seems high to me, and I've read that intake valve timing can increase the compression. I replaced the timing set a year ago, and though it's been running rich for a while, it doesn't seem to be running bad enough to be out a tooth.
Also, there doesn't seem to be readily available conversion charts for PSI to compression ratio. I've read that this has to do with temperature, elevation, valve timing, etc. Anybody have any experience with this kind of issue?
#1- 175 psi
#2- 182 psi
#3- 182 psi
#4- 172 psi
#5- 180 psi
#6- 167 psi
I made sure that the engine was warmed up, power to the coil disconnected, throttle body wide open, and all plugs removed. I turned the engine over 9 or 10 times and checked each cylinder at least twice. It's around 60 degrees outside, a little less than 1000' elevation.
It seems high to me, and I've read that intake valve timing can increase the compression. I replaced the timing set a year ago, and though it's been running rich for a while, it doesn't seem to be running bad enough to be out a tooth.
Also, there doesn't seem to be readily available conversion charts for PSI to compression ratio. I've read that this has to do with temperature, elevation, valve timing, etc. Anybody have any experience with this kind of issue?