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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
Guys, I'm sorry if this is a repeat of 1000 other posts but using the search feature I can't find what I'm looking for. I currently own a C5Z and intend to buy a C6Z in the near future. Everywhere I turn i hear about this heads issue, valve train issue, blown motors. I hear people say "I'm only going to buy a z06 that has its heads done already". I'm a noob here and I can't determine A) What's going on and B) is it fixed now? Something I read said that 2011+ it was completely gone and everything was fixed. Can any of you guys give me some color on this or point me in the direction where I could find it. If I'm looking for a used C6Z is there a specifc year or years I should look for or avoid?
Every LS7 has the potential for premature guide wear....so all C6Z's, 427 verts, Camaro Z/28's. GM addressed absolutely nothing....its all on the owners.
I too read about valve issues and decided to completely dismiss a C6Z as an option. Instead, I shopped nationwide for 9mos seeking a low-mileage V2 sedan w/ manual trans to absolutely no avail.
Eventually decided to reconsider and bite the bullet on a great C6Z opportunity that came my way. Fast forward to now - after having done the heads (plus other stuff) - I laugh when thinking about my earlier reservations. It is a total straightforward process and moderate expense, with plenty of capable shops around. #justdoit
I've had one for many years now. If I'm you, I don't want one that has had the heads done already. I'd rather have them done myself so I can get it exactly the way I want it and know the peeps that did the work.
Don't be afraid. It's well worth it just for the driving experience.
Everywhere I turn i hear about this heads issue, valve train issue, blown motors. I hear people say "I'm only going to buy a z06 that has its heads done already". I'm a noob here and I can't determine A) What's going on and B) is it fixed now? Something I read said that 2011+ it was completely gone and everything was fixed. Can any of you guys give me some color on this or point me in the direction where I could find it. If I'm looking for a used C6Z is there a specifc year or years I should look for or avoid?
Everywhere?
a) It's about valve guide(s) prematurely wearing (allegedly due to bad geometry) eventually breaking valve.
Cylinder inhales ventilating block. Game over.
While ALL LS7s are at issue, not ALL LS7s failed due to valve failure. Some did. Some didn't.
b) Some bought an extended warranty after B2B expired, effectively indemnifying against a catastrophic failure ('new' LS7 =beaucoup $) w/ warranty paying to replace LS7.
Providing, LS7 is left STOCK. No tune. No cam. No headers.
Others cut to the chase way sooner, had their heads rebuilt; and, once AM warranties run out others (like me) do likewise & put issue behind them.
Z06 ownership has to be experienced to put all the noise into perspective.
Driven a C6 Z06, yet?
If not, drive one.
Gain a better understanding why present owners love these cars, what makes them special.
Also why they willingly take proper preventative maintenance measures, like rebuilding heads.
BTW rebuilt heads are a stupid cheap investment for the joy of driving one of these gems.
I just bought an 07. Called AHP and have new heads on order. It's my plan to do this in my garage. Im nervous as all get out that im going to set the whole thing on fire without even trying but even knowing there was an issue i still test drove one and I had to have it afterwards.
One blown motor couldn't keep me away from owning another C6Z . Luckily, my first motor was under warranty, and this time around, I got the (majority out-of-spec) guides replaced, and will continue to enjoy the hell out of this awesome piece of automotive machinery .
AHP = American Heritage Performance seems to be one of the preferred, most reliable go-to places to get the heads fixed. Without question, just go for it.
i've had one for many years now. If i'm you, i don't want one that has had the heads done already. I'd rather have them done myself so i can get it exactly the way i want it and know the peeps that did the work.
Don't be afraid. It's well worth it just for the driving experience.
[QUO TE=BigKitty;1599218088]I have a 2008 Z06 with 2000 miles on the car and not sure if I should have this done.Is it best to buy the AHP heads or have the stock ones done?[/QUOTE]
Fixing the heads is easy, these cars are way to fun to pass on not getting one. There may be some bearing issues (pics below), who knows, everything can fail sooner or later. Heads are a problem, get them fixed, rather easy and you dont need to spend thousands and thousands to do it.
Even after you fix the heads sometimes that still doesnt help much, see above.
All LS7 engines (Z06, Z28 or crate) have the potential to have the head problem. It is luck of the draw whether any particular set were machined incorrectly by the GM supplier who made them. On my engine, 15 valve guides and seats were within spec at 32,000 miles, one was so far out the valve rattled around in the guide more like a pushrod.
04-10-2019, 01:00 PM
c6z heads
. Luckily, my first motor was under warranty, and this time around, I got the (majority out-of-spec) guides replaced, and will continue to enjoy the hell out of this awesome piece of automotive machinery 
.
