JamesRS

I was perusing some articles about our beloved LS7 and came across some conflicting statements that peaked my curiosity. I was under the impression that our LS7's had forged cranks and rods, but that our pistons were hypereutectic, or otherwise called cast. However today I found a few articles that state that our LS7's have forged pistons in them. Would you please clear this up for me. I'm not making any changes or doing anything that will require one over the other, but I would like to know which type we actually do have. Here are links to the articles that I was referring to.

Corvsport article

LS1 Tech article

Yet here on our forum we have an article that states that our LS7 pistons are hypereutectic aluminum.

Corvette Forum article

Would you all help clear this up for me, I'm most curious because of these conflicting statements.

-James

92rsz

Ls7 pistons are hypereutectic. Pretty sure the only ls engine that has factory forged pistons is the ls9

Trojan man

Depends on the ls7. The vettes are all hyper, but GM went and changed to forged pistons for the z28 Camaros. I don’t know what the create engines use, but they’re possibly forged as well

grinder11

Interesting stuff! Learned something new today. I thought all LS7s had hypereutectic pistons!

92rsz

No ls7 came with forged pistons. Some magazine articles wrongly stated it did. The reason was emissions/the pistons they used were satisfactory for the power output. The tighter piston to wall clearance with the hypereutectic pistons helped gm pass testing more easily. Only thing that changed for the z28 was the exhaust manifolds

grinder11

Accuracy in the media, including car magazines, is critical. Some people learn how to do things the wrong way if magazines are their sole, or primary source of how-to education. I've also read that LS7s came with piston oil squirters, which they did NOT!! MY LS7 did, because I paid around $400 to have the block specially machined for them. It uses Holley carb jets for the squirters. I was told the factory squirters would not clear the 4" stroke crank, hence no squirters.

Trojan man

I stand corrected, I dig around but couldn’t find any official source that mentioned the z28 getting a different piston, only several major car reviews at the time.

449er

LS7's have hypereutectic pistons

92rsz

I wish they would've done forged it might have made a few dropped valve engines fixable instead of shattering the pistons and liners and trashing the block

JamesRS

Thanks for clearing this up for me guys, it was just a curiosity, but the correct information is always best for possible future upgrades.

-James