compression on ej20g

woody.t · Post by **woody.t** » Mon Oct 24, 2011 12:13 am

what would be expected values for an ej20g on doing a compression... i think i remember being told ~150psi?

H-top · Post by **H-top** » Mon Oct 24, 2011 3:57 am

150 to 165 is good for a turbo.
That is consistant with 8.5:1 CR

the number is less important, you
should look for all the cylinders being
the same or within 5Psi

steptoe · Post by **steptoe** » Mon Oct 24, 2011 7:19 am

operating temp is also a consideration for comparison

RSR 555 · Post by **RSR 555** » Mon Oct 24, 2011 5:36 pm

Sounds about right but check the WSM and it will tell you the cold and hot readings.

Like H-Top has mentioned.. as long as the are withing cooee of each other then you'll be fine.

woody.t · Post by **woody.t** » Sun Oct 30, 2011 2:05 pm

can you do a compression test while the engine is out of the car.. like twist it over by hand or does it give lower readings..? with my reasoning i thought you'd be able to but the results i got on a wet and dry i really hope they're not an accurate depiction of the compression on the engine...

Post by **TOONGA** » Sun Oct 30, 2011 2:30 pm

If you can connect the engine to a gearbox and install the starter motor then crank the starter motor you will get accurate readings.

turning the motor by hand or with a ratchet won't give you a compression reading it will give you a reverse of the leak down process.

TOONGA

woody.t · Post by **woody.t** » Sun Oct 30, 2011 3:43 pm

thats what i wanted to hear

ahah