Slash8915

iTrader: (21)

So I'm looking at getting into a C6Z in about a month. I'm looking at an '08 or '09. But over on the corvette forum, there's a lot of talk about the LS7 self-destructing by blowing an exhaust valve. In a lot of cases, the cars were bone stock. This REALLY worries me. If you mention it, they get kind of pissy and won't really answer anything.

Can anyone on here shed some light on the subject? Just how common is this? Are certain years more likely to have problems?

neutron82

iTrader: (26)

are they dropping valves or what?... i know earlier c5's had a problem with breaking valve springs and sometimes the valve would drop and there goes the motor... not sure if the same thing is happening on the c6 though

DKM DWN

Interesting.... where did everyone go?

UTzo6

I think it's more of a hit or miss thing. I haven't had any issues.

zamora7

iTrader: (4)

Ive read about that issue as well. As a mater of fact i know a guy who had one before and self destructed the same way as well.

Ls1ChevyII1963

iTrader: (7)

Seen it many times on the ls7s while I was working at the dealership it's a spring issue at high rpms the valves would float and release the lash cap allowing the rocker to chew through the retainers. Or a few times it was just a broken spring allowing the valve to drop.

First thing I'm doing when I buy mine is installing a good set of dual springs.

D-Rod

Unfortunatly it is a problem. I heard all the talk for a while but didnt worry about it to much. While I was getting tuned by Formatto he highly suggested I get my heads checked out. Now I started thinking about it more and more and more LS7's were popping. Then I noticed I started using oil and had a puff of smoke on startup. I decided to do something about it and it saved my motor.
I could literally move the valve around in the guide mine were so bad. It only happened on my exhaust valves mainly. What I and many others think is the sodium filled guides are transferring to much heat up into the guide. I bought a set of heads that had SS valves and bronze guides. That is supposed to be the fix. I do not believe this is a "the sky is falling" type of problem. It def seems there is a problem and it has been noted by Katech, WCCH, Formatto, as well as other well know guru's in the GM world.

I just bought a supercharged Z06 and am going to have the heads send away very soon. I will update this thread with the condition of my current guides.

BTW- If you get a Z06, it is worth the investment to do a H/C anyways. You will get approx 100rwhp from a H/C package and it makes the car alot more fun to drive. My old car has a vararam, ported LS7 intake, slight port on the heads, TSP cam (242/250 .650" 144lsa), and Kooks headers and it went 10.14 for me in full weight.

Would I be afraid to buy a Z06? Hell no, I just bought another one knowing the problems. Would I leave the stock valves/guides in it? No way.

D-Rod

I forgot part of your question.......there have been more failures on '08's and prior. I think there have only been a couple '09's that have dropped valves. That doesnt mean '09's will not have the problem because you have to factor in that the car is newer and people dont have as many miles on them yet. I hope it is fixed but GM has not announced that there were any changes in the valvetrains.

Take my posts for what its worth. Alot of people still do not think there is a problem. I have been following it for a while and I disagree. That engine is to expensive not to make a small investment to protect it IMO.