Thread: Cracked pistons in SR20VE

^This.

I lost my first high comp motor due to bad injectors. Happened without any sign at all. The car ran like a raped ape until it popped. I went through and checked wiring and got a fresh set of injectors. New motor held up great till this day. I would say get a clean set of injectors or send your injectors out to get freshened up.

That Calum bin didn't work out for my car at all, it was freaking slow so I got a wideband and got 16.5 AFR up top, retuned to flat 13.0 AFR... I am gonna never trust in any other bin without getting AFR readings

Thats weird, it really doesnt even look like detonation damage and there is a lot of carbon buildup too. Usually lean conditions your pistons will turn white. Almost looks like it was something that got sucked in and hit. Maybe throttle body screws?

Another reason I say that is the top ring looks perfectly fine, usually with detonation that hard especially, the top rings will crack and break.

Who knows, you could have had an injectors or fuel pump give out and cause it but again, not the typical detonation damage ive seen.

How would a stock exhaust cause cracked pistons?

It could cause backpressure issues and heat the pistons up quick enough to cause problems but like I said usually when that happens youll get piston discoloration quick

I agree with Ashton on this look at the head for cylinder 3 &4 looks like maybe a screw was in there if you look good youll see the marks around the valves.

ive seen a bunch of toasted pistons i have never seen the top crack, always the ring glands that go, ive seen the top melt but not crack.

stratton.

How would a screw get into both # 3&4 cylinders. Maybe one of them but not both. He would know if he lost both TB screws.

Not only lose both screws but he would have to be in lift for them to fall into the cylinders lol. It would be a cool story if that is what happened.

You don't see a lot of 80k motors that died slowly from detonation do you? This could be intermittent bad detonation or pinging from many miles back. The piston finally gave way after your friend got on it really hard a few times.

I do agree though the stock exhaust could be a big problem if he was beating on it but the motor was probably compromised already. Sr20s just don't give up for no reason. Even VEs are fairly robust and run forever under normal conditions.