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Discussion Starter #1
so yeah the title speaks for its self... we got the car all built up... she is about ready to go to the body shop and we test run her... she ran great she was boosting pretty high... over 20psi... cuz we topped out the boost gauge half way through third gear... and we did it three quarters of the way through second gear. so i am guessing a good 25psi

then we noticed all of a sudden it started running really rich. so we slowed down... and then i noticed the dip stick had shot out of the tube... that was the first sign of blow by... we ran some tests and i washed the cylinder walls cuz it got so rich... fouled out all the plugs.. we ran a compression check...we are lossing massive compression in the 2nd 3rd and 4th cylinder... and cylinder number 1 has non what so ever... its believed that we a blew a hole in it.

we are ripping into the motor today and tomorrow to get for sure answers and then we will either rebuild it with new pistons and possibly bore it out or order a new motor...
 

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Not to be a ****, but that's why you don't run a 2.6 pulley. Maybe someday people will actually pay attention. The 2.6 overspins the supercharger by ALOT and you are putting way to much air into the cylinders and the fuel system just can't hold up because at that point not only are the injectors cooling the cylinders with the extra fuel but they are also starving them as well. Then the ring lands go.
 

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Discussion Starter #3
yep and you where right.... had i caught it statrting to get rich and shut it down and re-tune it we might have been able to save it and take the ections need to prevent that but it was to late... i was running her pretty good when it happened..

but now we can just rebuild it to hold the power.
 

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yep and you where right.... had i caught it statrting to get rich and shut it down and re-tune it we might have been able to save it and take the ections need to prevent that but it was to late... i was running her pretty good when it happened..

but now we can just rebuild it to hold the power.
Yeah that's the good side to blowing a motor you get to build another motor that is stronger and better.
 

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Woot! I just blew my motor too! but mine's because I hut a rock, killed my oil pan, and kept driving. Cool huh?

Na seriously though man that sucks!
 

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damn i guess you live and you learn
 

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Discussion Starter #8
well we pulled the cylinders last night... 1 is melted and the rest are cracked.... and there are chunks of pistons and rings in the crank case.
 

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Wow, bummer. Good luck with rebuild...
 

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Discussion Starter #10
so yeah, next step get my diamond forged pistons... called them up said they will hook me up with a set with rings and all for $450! now we need them sent out here asap so i can finish the build and then paint it before the first weekend in april! my deadline, big cobalt meet in chicago
 

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smaller pulley= more air= more heat Thats what killed your engine my friend
 

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Discussion Starter #12
... yeah we do know that...

and its smaller pulley= paster compression of air= heating of air when compressed

and also it went to rich the quickly leaned out... and the pistons are not forged and can only handle so much hp and boost... we were well past 20 psi when it blew by....
 

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looks like its time for a gmpp race block...
 

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Woot! I just blew my motor too! but mine's because I hut a rock, killed my oil pan, and kept driving. Cool huh?

Na seriously though man that sucks!
I've been there...I bottomed out on my g/f's road and I kept driving but it all leaked out on the ground and I saw that b4 I started the car up. I did that when it only had around 1000miles on it.
 

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Discussion Starter #17
basically the only weak point of the 2.0 LSJ ecotec is the pistons... the crank and rods are forged... if you can replace the pistons with forged one your motor will be capable of much more power.
 

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that sucks man but live and learn...then buy a ss/tc lol jk man Hope the motor works out.
 

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Discussion Starter #19
y by the SS TC... its got the smae internals as the LSJ for the most part... the part number on the pistons are different but they are still not forged and they still hold the same power as the other ones... i would still have to drop new pistons in before hitting the HP i am now. 350 will be the max crank power of those pistons too....
 

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Very nice i would love to see pics of the new ones you get and pics of the process of the build
 
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