Originally Posted by ZL-1

Looks like it might have been run hard on the track as allanlaw mentioned (brake pads and rotors shot at 5300 miles, rotor got so hot that it fried the boot on the tie rod end). Wonder how the boot on the left tie rod looks?

Originally Posted by ZL-1

Thats a subject that I've never been able to get all the answers on. A while ago I saw a GM service bulletin that said its the same engine, just the code was changed. At the Bash in April of 05 I copied down the VIN # of half a dozen or so Z06's; naturally they were all Y codes. A very reliable source told me that the workers at the PBC in Wixom had to put in a lot of overtime in June 05, changing pistons in LS7's they had already built. This would coincide with the last minute delay in startup of customer order production (the first orders, first scheduled with June build dates, were delayed into July). If indeed there was a piston design change, obviously all the regular production cars got the later design and all had an E code. But by June there were over 100 "captured fleet" Z06's running all over the country with Y codes. If indeed there was a piston design change, I seriously doubt they would have pulled engines from built cars to change pistons. And some sources say the LS7 was originally to have forged pistons. Could this have been the change, or just a change in the cast piston design? (The GM parts book doesn't show different pistons for Y or E, but that doesn't mean much).
Has anybody else heard anything on this subject?

( the source stated that all LS7's built prior to 6/15/05 were torn down due to major changes to the pistons, but I'm unable to find out if that includes the engines that were already in cars; I doubt it, which makes me wonder if those are the Y code cars).