should i rebuild this??

[PieEyedPiper]

I tested my engine's compression and I got the following results:

In order of left to right, facing the front of the car.
cyl 1 : 180psi
cyl 2 : 181psi
cyl 3 : 150psi wet: 240psi
cyl 4 : 148psi wet: 221psi

I guess this means I have bad rings?

What should I do in a situation like this, can I keep going and continue to mod my car? do I need a rebuild or engine swap?

Thanks.

 

[chris4g63t]

service limit is around 120psi

 

[xveganxcowboyx]

Isn't a large variation almost as bad as across the board low compression? I thought 20 or 25 psi difference was supposed to be too much.

My thoughts would be that it doesn't seem like it needs it immediately, but it might be something worth tackeling in the near future.

Maybe someone can comment on how long failing rings hold up under different levels of boost.

 

[92awddsm]

Before you begin to tear it down, I would run some seafoam or morpar combustion chamber cleaner through it. Afterwards, drive it a couple of days and recheck compression. I have seen where carbon has built up in the ring lands of the pistons and gave false compression readings. If this is the case, Your compression will come back up in the 2 low cylinders.

 

[PieEyedPiper]

alrighty, thanks.

Yeah I'll do a good seafoaming and report back.

btw, I think i read that a dif of 13psi between cylanders was bad news .

 

[BlandAnalogy]

how much air are you losing? and where are you losing it from? you can always use a stethescope to listen in on where air is escaping. if it holds pressure your compression should be great. check both intake and exhasut sides for leakage and the lower end which would be leaking past your piston rings. from my understanding you shouldnt be losing anymore than 30 psi's at max. you might wanna check specifications on your application....