I was on the highway last night testing my madz28 tune when i hit the gas and spun the engine up to 6200 rpms when i heard what sounded to me like i hit something in the road. well after that happened, the engine vibrated like crazy so obviously i thought i popped somethine in the engine. I drove to my house about a block away and killed it only to find that there was oil streaming off the back of the oil pan........the back of it......and the hole was poking IN instead of OUT. I put my investigational skills to the test to figure out that the counterweight came loose, poked a hole in the back of the oil pan, then LODGED itsself in the starter like hot knife through butter. i guess what im trying to ask is, is this normal for stock flexplates on mid HP motors?

 

I cracked my flexplate in about 13 places with bolt-ons and a 100 shot. Stock 5700RPM shift points..

I'm not surprised since it IS a B4C.

 

I don,t think its normal.
I just pulled my stock flexplate off and it had 160k and lots of 6250 rev limit hits on it. It was not cracked nor did it look bad in any way.

 

well this thing took a crap right at 6200 on the 2-3 shift. it cracked right where the counterweight was welded and thus sending the weight into orbit.

 

I had the flexplate crack in 3 places (hmmm, right in line with all 3 bolts ) on my LS1, and I've heard of them failing before, but I never knew LT1's had flexplate issues? You probably just got that bad 1 in a bunch?

 

lucky me..... HA

 

My flexplate held up to low 12's and 6800 rpm shifts. I just pulled it off and it looked fine. Sorry to hear about that. That's a lot of work you have to do now. That really sucks.

 

replaced it last night and it wasnt too hard..... about 2 hours total. i pulled the driveshaft off, the torque arm loose, pulled all but 2 tranny bolts then replaced those with LONG tranny bolts and slid it back enough to where i could get the replace the flexplate.