Sorry to hear this Jeff.
If you were closer I'd say you could stop by and pick up my original 99 SSEi shortblock, which I just popped the heads off of and found to have excellent cylinder walls. Pistons look great too. I have to load it up and bring it back into town here and put on a engine stand and rotate it to check the rod and main bearings.
Heck, if you want to pay shipping I could strap it on a pallet of a smaller version and slip it on a Greyhound for the cost of shipping.

a little too much compression maybe? The heat that #4 get is a little more than the other 5 so maybe that raised the pressure just a tad. just a theory, I could be talking out my *** :?

For OEM H/G maybe... I was at 190 at idle with my GenV setup and never had any issues.

No way he'* even close to that..


Boost stacking issue (boost creep) issue???

Also I think you answered you own question:
Thats more than enough KR to pop a piston if your at a certain level. Which sounds like you may be....I popped pistons at 2-3*KR...With the GenV (IDD 2006)

How much boost are you running???

Are you using a ported L67 LIM??? Non equal flow in the LIM??? We know the L67 LIM sucks anyways, and if ported incorrectly the problem can be 10times worse..

He'* running 13psi, but I'll agree that is more than enough. I have one of a handful of popped pistons from last year. That didn't take much either. I was also running about 13psi, but ran into a little unexpected issue.

Not a MAP issue for sure... what are the MAF readings???? Getting close to 11500???

So what happens if you exceed 11,500 Hz :?:

Only 13 psi :?:

Only 2-3 Kr :?:

OEM headgasket with GenV :?:

You guys are getting me scared now. :?
How come mine hasn't popped yet :?:

PSI is just what the engine couldn't get into the cylinder that cycle. The question is, how much air was actually moving? Also, what would the dynamic compression ratio figure out to be? I think 11,500hz is where the MAF pegs... could be 100% wrong on that though.

I was just using mine as an example... please ignore
And I ran .052 MLS with the GenV.


at 11500 the MAF has no reference value in the PCM. under 14.7lbs of boost the MAP is supossed to pick up the reading.

16psi, the MAP has run out... 10,500 on the LS1 MAF.

the stock hg is supposed to be the fail-safe. it was thie first time, not so lucky this time. I just rememebred I reused the #4 plug after the first hg pop. I wonder is it was cracked. That might just have been it. No way to know except to rule everything else out.

Guys, KR is the pcm retarding spark to a safe level where knock subsides... A little KR is fine. When you exceed max KR and it'* still knocking, that'* a problem... I was only at 5*KR with a max 10 available.

Um...no its not! It tells you to GET OFF THE GAS....NOW!!

I don't know all the specifics of your build, but I will assume that your pushing the limits. And when you get to that level KR is bad at any point.

I have been cruising at 1-3* KR.. then boom same thing that happened to you. Been there done that.

You can say a little is fine...but you'll have a lot more of these threads.

A max of 10* of KR available???? WTF does that mean? I had 8 at one point, and lost 4 pistons....... I had 7* available before the PCM should have shut me down.

I will agree that with anyone that a twin charge setup is a PITA to tune....and you have to throw out the low HP rules (a few degrees of KR is fine). You tune to be PERFECT! No options....well one option, and we see the pics of option 2.


I'm sorry if I'm coming of like a dick...but I popped 5 motors and 14 pistons in 2006....all I needed was someone like me to tell me what I'm telling you.