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Piston Ring Gremlins.....

On a more serious note, stress is normally what does it, you stress metal and it becomes brittle and fractures. the stress can be caused by excessive temps or pressures differences....well thats what i been told neway :P

^^ agreed, age plays a part aswell.

If the motor is a bit tired, dont run lots of boost into it, just causes more issues

Motors can also ingest crap like comp/turbine wheels which generally doesnt help things either

What a dumb question.

Rings are made from metal, and metal can never be alive. So you can never kill a ring if it was never alive in the first place.

Do you mean break, wear out, fail to seal, or what exactly ?

If you ask a proper question, you will quite likely get a proper answer.

What a dumb question.

Rings are made from metal, and metal can never be alive. So you can never kill a ring if it was never alive in the first place.

Do you mean break, wear out, fail to seal, or what exactly ?

If you ask a proper question, you will quite likely get a proper answer.

wear out/fail to seal

Wear out....

High mileage, bore piston and ring scoring from lack of air cleaner or contaminated oil.

Failing to seal....

Not run in properly, excessive ring to piston groove side clearance, rings gummed up in piston grooves due to sludge and varnish from crap mineral oil, excessive piston rock caused by use of unsuitable forged pistons.

Broken rings....

Ring gap too small, detonation.

Edited by Warpspeed
^^ agreed, age plays a part aswell.

If the motor is a bit tired, dont run lots of boost into it, just causes more issues

Definitely... my old rb20 was fine at 10-12psi for 12 months or so.. dry as a nun's __ ... Soon as I screwed in 16psi (with tune) it was showing a heap of blowby, and poor idling after only a couple of months after that.

Nothing surer to kill an old engine's rings than boost.

im not too sure about my stock bottem end when i get close to the 260kw mark, ive raced my car flat out and drive it very hard on the street and not 1 bit of blow by in my catch can. Its on roughly 11 - 12 psi everyday. its also done 108,000kz and using motul 300v chrono.

Edited by LTHLRB

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