Pulled out piston #4 today..."its Jaw dropping"(with pics)

[ItalianJoe1]

Mine did the same, it was 210-210-210-140 when I tested, and the side of the piston had the same symptom. I also had some of the material below the oil ring come off, it was down in the oil pan. Not much, but still something.

To be fair though, I drove the car for probably 4 months after I popped the piston, so I don't know if that happened at the same time or not.

[cobaltguy889]

yea like whats funny is the day that i was driving to get some tuning, I walked a bolted early 90s 5.0 mustang that was talking shit at the stoplight. then we ran a compression test after we found that we were getting misfire. First thing i thought was wtf, i put like a bus length on a mustang this morning. and even after the compression test the car still moved pretty good.

[ralliartist]

if only GM didn't plague is with weak ass pistons.

ah well, I don't have that problem anymore.

[cobaltguy889]

yep me neither lol...and i'm being extra cautious and getting my rods cryo treated next week. i know it doesn't make a HUGE difference, but any help is something.

As crazy hard as people think it is to do this, it really isn't that hard on these cars.

[cgrammer]

Oh shiznit

[Johnboy12358]

Son of a bitch dude! Did you have AFR or EGT gauges? Did you ever notice anything funky there from that bad tune you mentioned?

[cobaltguy889]

Not really. When we went to tune and were noticing a misfire on hptuners, it had kind of a problem holding a solid afr.

[BCobaltSS]

sorry to hear man . With all these stories lately I'm afraid to run a compression test

[cobaltguy889]

its better to know right away rather than be worried and put it off till things get worse.

[thought]

Yeah GM's pistons can handle GM parts and tune just fine. Don't blame them. Have a look on NASIOC if you think it's a GM-only thing to put pistons that can only handle stock power.

Am I correct in the fact that our stock fuel system causes lean conditions in #4? So proper fuelling would solve the root cause, right? Tuners please chime in, so I know if I should buy pistons or just return style system lol!

[cobaltguy889]

the pistons are the weakest part in our cars. but then again, BCP is hitting 400+ hp on a stock mtor with a turbo. Its all about tuning, cooling mods, and yes, keeping up with fuel. But usually bigger injectors will be enough fuel wise, unless your shooting for huge numbers. Oh, and yes, #4 is always the first to lean out...

[ebristol]

Originally Posted by thought

Am I correct in the fact that our stock fuel system causes lean conditions in #4? So proper fuelling would solve the root cause, right? Tuners please chime in, so I know if I should buy pistons or just return style system lol!

I don't think the problem has been determined 100%. Some people think that since the #4 cylinder is the last in the fuel rail it get less fuel then the others and that is why it fails.

Some people think that the way the SC is mounted and the way the Intake Manifold is designed that more air flows into the #4 cylinder.

I don't think anyone knows for sure.

Ottp just added the new Siemens 80# fuel injectors btw...

Originally Posted by cobaltguy889

the pistons are the weakest part in our cars.

Weird huh?

I like your new sig!

[cobaltguy889]

lol TY Most of the parts I have bought have been off the forum for the turbo and the rebuild, so i figured i'd give thanks! lol

[shadowfaxss]

Are you going with different pistons?

[cobaltguy889]

yea, i already have diamond racing forged pistons that i bought through OTTP

[krazycobalt]

Your lucky my friend. Very very lucky

[blackbolt89]

"granny shiftin not double clutchin' like you should, now me and the mad scientist have to tear apart the block and replace the piston rings you fried"

i'm really surprised no one quoted that before me. lol

but really! think of this as a good thing! now you can get all new pistons!!

[cobaltguy889]

i don't want no fast and furious in my thread lol...