hey do we have ne out there for our car?? i blew my engine and im looking to build it stronger and want to put them in to run more boost safely

or are there oversized pistons out there for our cars cause idk if i did ne scaring the the cylinder walls i might have to bore out and used oversized ones and would that work on the stock head??
for a good price
thanks

 

Check Wiseco Pistons.

Take your engine apart and make sure you don't need to re-sleeve the engine if the scrathes in the cylinder walls aren't scratched deep enough where you would have to re-sleeve them again.

Are you staying with the M62?

Did you find out why your engine "blew"?

 

Wiseco makes 8.9 and 10.1 comp pistons. But they are for the 2.2 so you would also need 2.2 rods. Diamond makes 9.5-10-10.5 for stock rods. I believe both make .5mm overbore as well.

 

Also using a Cometic L61 head gasket on an LSJ should drop compression by about half a point.

 

Why is that?

 

It's thicker

 

I know I am

 

hahaha

 

yeah im not sure yet, i know im goin to need number 2 cylinder piston no matter what, thinkin the tune was too lean and the spark spark plug came apart and wrecked the piston, heads off and the#2 top is chipped and theres all oil in the exhaust port, the car ran after it blew so i know its not seized but ill have to rotate the crank and see if im screwed.....

 

I'm just going to ask just to make sure but did you have a Wideband Gauge or anything gauges at all? What "tune" were you running? Did you have any aftercooler upgrades? What plugs were you running?

 

im under my buddys name who im helpin rebuild the car, he says he got a knock off kid who claimed to know what he was doin but we obviously we know what the outcome was, he has no wideband or anythin, sounds like he was tryin to save money in all the wrong places, umm i found a sleeve online for 107, r these motors sleeved where ya can replace a bad cylinder like in this situation? "looks" like they r...... we're goin to prob fix the block and put some lower comp pistons in since i have to replace the one anyway... and build the head while its off

 

Darton Sleeves makes sleeves for the ECOTEC engines (both L61 & LSJ since they are the same bore).

Lowering the compression would make him lose power rather than gain power if he's staying at the same boost pressure. This is why people are opting to raise the compression. It just depends on what he's trying to do ultimately.

AND!

Tell him to get a freakin Wideband, an Interceptor Gauge and a Cobra Heat Exchanger. After that, he should be set.

 

If the Darton kit is too much, you can get the stock sleeves from GM too. Part #88984129. GMPartsDirect.com has them pretty cheap, or from your local dealer. From what I read, new sleeves from GM come all set to go. No need to hone. Just put them in, cut them to match the block deck and your good to go. I believe GM has a tool to remove/replace the sleeves. Another tool the cut them too.

If the block is coming out and going to a machine shop, you might just want to have them overbore it. Could be cheaper, would be a bit unique too. But that depends on how deep the scratches are I guess.

 

What he said.

 

mahle makes an 8.5:1 which is holding up good from the boost levels we're pushing. but they've only got 6 dyno pulls on them, we'll see if they stick together after a couple of track runs once they open.

 

thanks for the feedback guys, i always thought since your runnin boost that ya want lower compression.... he does have the stage2 GM kit but i dont know what or if that raises comp to......i have a 02 ZX2 with a head that i milled .060 and raised the compession to 10.4/1 but thats N/A though, GMpartsdirect also has 10.5/1 piston set which is a possibility also....so the outcome here is to resleeve the #2 cylinder if i have to and R+R the piston cause its chipped..... in doin so im (we're) possibly takin the route where i resleeve the block and put all new either lower/higher comp. pistons in......

wut do u guys think of twincharging this beast??

 

Would definitely do low comp pistons then. Either do the Mahle pistons, or get the Wiseco ones with a L61 head gasket. With that you can also get stronger 2.2 rods such as Eagles.

 

don't waste your money, just do a straight turbo swap unless the sole purpose of your car is to run around and say "i have a turbo and a supercharger"

 

Side note on the Mahle Pistons. Apparently they don't fit any of the motors as is. So if you really want them, and can still find them... You will probably need to go to a machine shop to get them custom fitted.

https://www.cobaltss.net/forums/show...7&postcount=75

 

That's not a good way to lower compression. It can actually cause more knock doing it that way.

 

It accomplishes the same as changing pistons. Total volume at top dead center is either reduced or enlarged. Head gaskets have nothing to do with knock.

 

Are you familiar with quench height?

EDIT: This is typical for a lot of people that come to this site. I try to inform people of things they're not familiar with. Whether or not any of you believe me is up to you. If you'd like me to elaborate I will. I'll be glad to. But I'm not going to continue trying to explain things if nobody wants to learn.

Why would I say such a thing if it weren't true? Just because you've never heard of it doesn't mean it isn't true. Gasket thickness plays a huge roll in the combustion cycle. If you'd like me to explain, I will. If not, then look it up. Do research on it, learn the facts, then come back and say it has nothing to do with knock again. Then I'll call you a bold face liar.

Until then, you're just uneducated and it would be unfair for me to call you a liar.

 

Not saying that you're lying or anything but evidentally (according to you), he is incorrect. Either correct him or move on. Don't take it personally or anything like you are showing to be. You just made 2 big paragraphs complaining when you could have just explained to him why he is incorrect in a polite manner.

 

We are talking about Ecotec motors FYI, head gasket thickness has no bearing on detonation, because Ecotecs don't have a quench area.

Tell me where you see a quench area in this photo. This is WSFrazier's head we pulled off last week, an LSJ.

Before you flame and call people liars, please learn to at least be somewhat correct.

 

p0nwt3d!