I got compression test results for my stock H22a1: 180,180,180,175psi.
What is the acceptable variation for this type of engine? The manual spec is 185psi, which makes me question whether my engine still has 'good' compression. Does anybody else have some reslults?

Its a 96SRV w/ 150,000Km (93,000miles) and 10:1 compression (stock).

 

Damn, that's still great. You expect a little wear on the rings. As long as the #'s are all still within 10% of eachother, you're fine.

I think Honda318dx was down in the lower hundreds before he decided to replace his. LOL What was it Corey, like... 112's? hahaha

 

yeah your right on with those numbers - no worries..
And for those of you with Si Preludes.. you will run lower numbers than the VTECs.

 

what does it usually mean when the numbers are off?? mine are..
1 150
2 threads eaten so couldnt test
3 180
4 180

 

I got more insight into compression testing:
There is some variation between compression gauge readings. Usually they are a good reference, but not exact. A lot of things can change your static compression reading such as Cranking RPM, Throttle closed or not, If there is fuel Still being sprayed into the cylinders during the test (this is most common), etc. The best diagnosis is to do a "Cylinder leakage test" also Known as a "leak down" this will give you better peice of mind about what is really going on with the car. You use high pressure air to do this.

Therefore, there will always be variation due to reading error, my results are good enough for me, and the car still pushes me back into my seat.

 

How exactly do you do a compression test? BTW, what mods have you done MechEng?

 

sagaprelude: did you try a wet compression test?

 

SagaPrelude your numbers look off...
Cylinder1 does not seem too good.

I did one the other day as well.
My concerned with one of my cylinders but it isn't too too off
cyinder 1:208. 2:215, 3:195, 4:213

 

Basically: you use an air pressure gauge that screws into the spark plug threads. You crank the engine and measure the pressure reading in psi (pounds per square inch) or kPa (kilo pascals). 14.7psi = 101.3kPa = 1 atmosphere. If you don't have the money to do a ring and valve job don't even bother.

I just got the car, so no mods yet except for a killer alarm. In the summer I might install an underdrive accesory pulley kit. I only want to do the ps but the kit comes with the Alternator too... stupid. I also might install the AEM intake if it doesn't hurt low end torque too much, or I will take out my intake resonator.

 

1-112
2-100
3-90
4-100 with a bad leak down

my car is in the shop as we speak

 

Ouch that does not sound good.

My prelude @ 8.8:1 hits 150-155.