Respectable Compression Rating?

[iknowyoulike]

Hey guys i would like to know what the majority of you guys got as far as testing the compression of your KA motors? How do i know what's okay and what's bad? I tested my motor and i got 140/130/125/130 is that good or bad? my motor currently has about 150k on it and im hoping to go turbo it if all goes well. Any opinion/advice is my result still worthy of supporting boost? or should i just go for a rebuilt first? thanks guys.

[ftrs13]

sorry to be the bearer of bad news, but that engine is toast.
and I mean this in the nicest way ... I hope you screwed up something fierce when testing that.

most guys look for around 180

[skatanic28]

was this with the engine warm? if so, those do seem pretty low. usually want to be over 160 with #'s pretty close between all the cylinders. try adding a bit of oil to each plug hole and see if the numbers rise.

[Titan]

Numbers aren't always the best way to judge. Who knows, the gauge may be off.

More importantly is how close the numbers are to each other.

I tested mine 2 days ago. 151 across the board with 0.5 psi max difference. And I'm 3 weeks away from turboing mine.

The FSM says it should not exceed 14 psi difference along the cylinders, so that's what would have me worried most about your motor.

[ftrs13]

well, I just went across my engine the other day and had 145-152 across the board, 7 psi difference, max to min. I am turbod and trying to solve the mystery behind my complete lack of power. I suspect that it is the motor itself.

btw this is a KAE so the compression numbers should be slightly lower than the KADE because of lower compression.

[iknowyoulike]

okay guys so i figured out why the numbers were so low. IT WAS CAUSE I DID IT WRONG DUH!!! Anyways did a retest and heres the results:165/165/165/165 please tell me this is good thanks.

[Steeles]

thats fine again the important thing is consistany between the cylinders. engine isnt toast

[skatanic28]

did you not heat up the motor and keep it at WOT the first time?
good to see the new numbers though.

[iknowyoulike]

okay heres how NOT to do the test!! i removed all the plugs and i took the reading on the device every time it pulsated three times. based on thee four stroke of a internal combustion motor. that's wat i was told to do. also the motor was warmed up when i did it. But it wasn't at wide open throttle.

Here's how to do it for anyone that is considering doing one.
-First step is to take the car out for a cruise to warm up the motor if it isn't already warmed up.
-remove the 10V fuse that goes into the fuel pump.Crank the motor a couple times to depressurize the system.
-remove all the Wires and plugs.
-Insert the compression tester and have a buddy crank the motor at WOT
-To take the reading wait till the needle can't/won't rise anymore and thats the reading for the particular cylinder..
-repeat for remaining cylinders and pray for the best.....

This is how i did it..i was told it was the right way and i'm sticking to it hope this helps anyone in need of a test. Also thanks to everyone for their help.:wiggle: