My compression sucks!
 

Did a compression test yesterday.

20 140 30 20

That's what my cylinders showed on the compression tester. What could be the problem? Piston rings? Timing belt not set correctly to TDC? I'm getting frustrated, I just wanna get another motor instead of having to pay so much just to have piston rings replaced...

Re: My compression sucks!
 

your motor is fubared. Most likely rings.

Re: My compression sucks!
 

was the throttle held open? I dunno even if it was man that way way to low. Nows a good time to rebuild or drop another one in.

Re: My compression sucks!
 

i got a friend who did his with the throttle shut and again at WOT

he got the same numbers. any clue as to why

its a stock gsr compression was something like 140 155 160 155

this thing ------- rips still, even when his compression should be close to 200

Re: My compression sucks!
 

if your at tdc and all the valves are closed it shouldn't matter if the throttle body is open or not right? wouldn't you still get the same numbers?

Re: My compression sucks!
 

no

Re: My compression sucks!
 

why not?

Re: My compression sucks!
 

because ur creating vaccuum and the pressure is reduced

Re: My compression sucks!
 

Thank you guys for all of the advice. My friend and I took the motor apart, and yes, the rings were FUBAR. So, more downtime.

:(

More to come...

Re: My compression sucks!
 

i bet that thing is fast as ---- with compression like that ;)

Re: My compression sucks!
 

UPDATE:

New frickin' Piston Rings, Ported Intake/Exhaust Ports, and Polished Cylinder walls. Block looks new, put head back on. Started like a Monster...

;D

Re: My compression sucks!
 

"polished Cylinder Walls"??????????/

I hope you're mistaken

Re: My compression sucks!
 

do you mean honed?

Re: My compression sucks!
 

Yeah, honed out the glaze. Still working on the lingo...

Re: My compression sucks!
 

For referance my D16Z6.........

throttle closed, 115-120 psi
throttle open, 175-180 psi

Re: My compression sucks!
 

Took it for a test drive today after a 45-minute minute break-in period. Man, it ------' hauls-ass! I can the sweet sound of a tire screech every time I shift into the next gear. It's ------' beautiful. Thanks again for the advice and help, y'all.

Re: My compression sucks!
 

same for a d15b vtec
maybe 5 psi more

Re: My compression sucks!
 

man, my z6 made 210psi across the board, i think it has circus freak™ brand rings.

Re: My compression sucks!
 

no, you probably just have alot of carbon build up ;D

Re: My compression sucks!
 

bingo