Compression Test Results

[slogti]

Finally got around to doing a compression check on my car at 51k miles the motor has 170 psi across the board. I am pleased with this but I have seen some others have a constant 190 or so. Is there a sort of minimum psi that I should be looking for I know all the cylinders have to be within 40 psi variance but shouldn't the motor not go lower than like 100?

 

[PowerDemon]

I thought you shouldn’t be below 120PSI.

 

[Twist1]

Numbers mean nothing. Gauges don't read the same. Cars aren't the same.

What you want to see is the cylinders within 5 of each other and it's fine

 

[donefor]

From the documentation.

 

[billbadass]

only thing that matters is no single cylinder is far off from the other ones.

and tbh I've had cars with pretty big differences between cylinders that we sprayed with nitrous and abused for years and made good power on the dyno anyway without issue so at this point i'd need to see one cylinder REALLY far off from the other ones to care enough to go and do something about it.

 

[JerseyDrew77]

Numbers mean nothing. Gauges don't read the same. Cars aren't the same.

What you want to see is the cylinders within 5 of each other and it's fine

Yep, what Twist said. My car is 122 across all 4 cylinders.

 

[Jacobmk7]

Mines 185 on all cylinders

 

[ErBall]

145 across 4. I was worried when i first found this, but that was roughly 40k miles ago, and i recently checked it and it's still the same. Car runs great, but doesn't like timing, i've assumed this was related.

 

[donefor]

140 across, nevertheless sounds like a box of rocks when cold