rebuilding

[u/crimsonfuhren]

2014 STI in Ontario Canada

Second owner

mods are COBB DOWNPIPE - CATTED W/ GESI CONVERTER, INVIDIA Q300 STAINLESS STEEL EXHAUST, COBB SF INTAKE with box, AEM 340LPH, open source tune on a dyno with dyno sheet in pictures

Currently rebuilding my own EJ257 from ringland failure that caused me to deal with uncle Rodney.
I pulled out what I thought was a factory size piston but it was a 99.75mm piston out of a 100mm bore and my ring gap from the old ring was at 0.30mm.

Pressure test from 2 years ago were at 150 psi with only with cylinder at 145 psi.

A general question on how cooked am I? Ideas? General humor and some degeneracy is welcomed granted something helpful is said afterwards.

And has anyone ever come across this act of blasphemy when rebuilding before since my tuner did say it looks like my block was apart before.

[u/Equana]

A tuned turbo Subaru with a bad engine?? Say it isn't so. Add boost, get boosty results.

So one bore is 100mm, what is the standard size and what are the other 3? What else, if anything is bent. Clearly it needs a rebuild and dare I say it...stronger, more expensive parts. And definitely a wider ring gap.

Can't answer how cooked you are, I don't know how many bundles of $100 bills you have.

[u/crimsonfuhren → u/Equana]

Should have been a bit more clear. The previous owner had it apparently over bored to 100mm based on the quick measurement I took on all 4 cylinders but they put in 99.75mm pistons instead again don't ask me why but they used piston rings that were meant for a 100mm bore.
These are my findings on the parts I have removed I'm going to take proper cylinder measurements tomorrow for out of roundness.

Just never thought that someone would mix and match different size parts like that but it did survive 100,000 KMs of me wailing on it plus cooling issues from old cooling hoses with a small hole which would only open up when it got hot enough which I had to chase for 4 months last year.