Considering LS7: Question on head & valve train failure

[NDAGRUV]

NOTE: I "SEARCHED" "ZO6" TO BE SURE THAT I HAD NOT TOUCHED ON THIS TOPIC HERE, AND THE SEARCH CAME BACK "NO" - SO I MADE THIS POST. THEN I FOUND ONE I POSTED ON THE ZO6 HERE EARLIER - GO FIGURE!! THIS CONCERNS THE LS7 ENGINE, ANYWAY.

I am considering a ZO6 and have heard "HORROR STORIES" regarding the failure of the valve train (mainly) resulting in some folks buying LS7 equipped Corvettes and soon after doing a head swap just to stay away from "grenading engines".

Any REAL experience on this anyone?

How about you Professional Mechanics and Corvette Specialty Shops - anything to report?

I've been researching all over (Corvette Forum, Corvette Action Center, etc.) and I must admit that I'm STILL a little concerned as there is "evidence" for both sides.

I am hoping that here locally (where we ALL enjoy LS7's) that I might find more "confidence inspiring news".

THANKS Y'ALL!!!!!!!!!!!

Also, yes Bob I DO have "sleep issues".

I'll be HAPPY to SHARE them with ya!...............................

[uncledibble]

my 2007 z06 has 84k miles on it. From all the research and service records I have (2nd owner) I cannot find any evidence that the heads have been reworked. IN addition to this it shows zero signs of any of the "issues" folks claim proceed a valve dropping. That said, I am trying to contact the PO to see if by chance he has already addressed this issue as he has a very extensive service history at Van's and it appears he fixed every little issue they ever suggested. My LS7 is bone stock aside form the manual exhaust switch I built and installed myself.

That being said, I have been working with a few of the local shops on some pricing to get my heads re-worked to eliminate any possible issue and get some peace of mind. Part of me wants to roll the dice and spend those dollars on headers, CAI and possibly a Cam while my more responsible side says bite the bullet fix the heads and go from there. With my mileage it make my decision that much more difficult as another school of thought might be to run the heck out of this higher mileage engine and when/if it goes build a new one that makes huge power and is bullet proof to my own specifications.

Good luck to you I can totally relate to your concerns.

.

[Unreal]

My heads were 3x the service limit at 18k miles. My friends were the same. A friend of mine dropped a valve with 20k miles, it cost him $8k to repair it and he found a cheap used short block to use. I sold my factory motor to a guy that dropped a valve at 11k and again at 23k. I've seen 1 drop in person, and seen the results. It isn't pretty. If it happens, pray for it to be at idle or when you are stopped. Oil and chunks of metal everywhere. I've seen 6-7 sets of heads in person from them being pulled off, and not one has looked good.

If you get a Z, just plan on the $1300-3000 to get the heads gone through. Much better piece of mind. As far as I see it valve guides/etc are going to be considered wear items and I'll pull my heads every 20k or so just to inspect and repair as needed.

Or buy a newer one, keep it bone stock until the 100k/5 year warranty is up and let GM fix it if/when it breaks. I rather buy an older one and spend the money on mods to make it more fun.

[Ted Y]

http://www.arizonacorvetteenthusiasts.net/arizonavette/forums/index.php?showtopic=21851&page=1

[Drewstein]

I just tell people that if they think they can afford a C6 Z but they can't afford $2500-$3k for heads, they can't afford a C6 Z. Just consider it part of the purchase price IMO. Trying to save that money isn't worth the risk.

[Unreal]

I just tell people that if they think they can afford a C6 Z but they can't afford $2500-$3k for heads, they can't afford a C6 Z. Just consider it part of the purchase price IMO. Trying to save that money isn't worth the risk.

Exactly, first time you have to replace the tires it will be close to that. If you can't spend $2500 on maintenance then find a different car.

[ChadC]

NDAGRUV

NDAGRUV,

I am objective reader. I too was in the same boat as you some 3+ months ago.

One issue with the internet is one person has an issue and it can be relayed many many times, seeming like there is a bigger issue than there is.

in my opinion there is a lot of misinformation on the LS7 head.

- is there a problem. YES

- how wide spread. unknown

- is it now fixed. unknown

-is Stainless Steel valves the cure. unknown

I will tell you that I spent money to have my heads swapped out with SS intake and exhaust valves ( yes, yes, I know not the Uber performance). Just last night I took the opturnity to remove a spring off of the old heads (exhaust valve) and let the valve move forward 1/2 inch, and wiggle it.

..holy... lee.....shit

im 100000% glad I did the swap. Ill make a post with pictures and FACTUAL FIRST hand data collection in the next 6 days or so.

[Steve@LPM]

It is hit and miss. Like others have said, some people have gone 75k miles with no problems, and others drop a valve under 20k miles. The options you have are to have them inspected to make sure they are within spec or just have them sent out to WCCH and get them gone through for piece of mind. We will be stocking an already updated set so that the turn around time will be 1-2 days instead of 2 weeks.

[HOXXOH]

my 2007 z06 has 84k miles on it. From all the research and service records I have (2nd owner) I cannot find any evidence that the heads have been reworked. IN addition to this it shows zero signs of any of the "issues" folks claim proceed a valve dropping. That said, I am trying to contact the PO to see if by chance he has already addressed this issue as he has a very extensive service history at Van's and it appears he fixed every little issue they ever suggested. My LS7 is bone stock aside form the manual exhaust switch I built and installed myself.

That being said, I have been working with a few of the local shops on some pricing to get my heads re-worked to eliminate any possible issue and get some peace of mind. Part of me wants to roll the dice and spend those dollars on headers, CAI and possibly a Cam while my more responsible side says bite the bullet fix the heads and go from there. With my mileage it make my decision that much more difficult as another school of thought might be to run the heck out of this higher mileage engine and when/if it goes build a new one that makes huge power and is bullet proof to my own specifications.

Good luck to you I can totally relate to your concerns.

.

You should correct that to read "build a new one that makes huge power or is bullet proof"

[Mregor]

I have all the same concerns with no answers. I don't think valves are only issues. Lots of bearing failures recently as well. It's scaring me away to other cars. If it was just the heads, I can live with that. One time fix, worry over. But with all the main bearing failures on newer models means I have to get heads done, find one still under warranty, make damn sure no mods were done to any car that would void the warranty. Too damn hard. I want C7 but was going to get Z until 3rd tear or so. now, I'm leaning to C5Z or different car altogether. I've had a vette until I sold my 2009 in Dec for 20 years straight and I may end up in a Ford or Porsche.

[Two Fangs]

OK, what I have gleaned are the following observations.

First, bearings. You do not have to worry about bearing failure as long as you ensure the oil is hot before you beat on the car. Back out of the garage and start doing burnouts and brodies, you are asking for it in any car, Z06 included.

Second, valves. It is not the hollow-stemmed voodoo valves in the exhaust that are causing these failures. The problem is with the guides. Guys that went to stainless solid valves, but did not change the valve guides because their cars had low miles, are beginning to see failures of the solid valves. The guys that went to bronze guides, be it solid or hollow stemmed exhaust valves are still driving and smiling.

If you are buying a C6 Z06 that has stock valve guides, do yourself a favor and have the heads reworked. It does cost, but the peace of mind from being able to enjoy the car and not worry about failure far outweigh the monetary expense you will incur.

[MOTV8]

/thread

[NDAGRUV]

Thank you ALL, so very much!!

While I am in tune with the issue of the valve guides (mainly) being the issue, I'm hearing OTHER items come to the fore front.

I "WAS" under the impression that Chevrolet's Corvette ZO6 was a bullet proof "step up" in the performance world, and what I'm finding is that my current LS3 powered "smile maker" is the tried & true horse that I (maybe) ought to stay on.(?)

First off, I LOVE PERFORMANCE, AS WELL AS "CANYON CARVING", that's why I began looking to the ZO6. HOWEVER, I am finding that this "head issue" does not limit itself to ANY particular year - ALL 2005 and up to 2013 models are fair game for July 4th fireworks!!

Since there IS this problem, WHY hasn't Chevy MANNED UP??????

Oh yeah, they have a "TSB", but it's about as nebulous as a politician!! (Please excuse my use of foul language!)

I have no problem with the attributes of the ZO6 I'm looking at, and I fully intend to have at least a 48k mile warranty included in the deal (as it's an "08), IF I buy it. THE PROBLEM is I don't like being "in the dark" as to "when" this aircraft is going to crash!! I would like to at least get my parachute on, ya' know?

IF I HAVE THE HEADS DONE/REPLACED SOON AFTER PURCHASE, CAN I BE SO FOOLISH AS TO BELIEVE THAT IT WILL BE A DEPENDABLE RIDE UNDER ME???? (considering it IS a motor vehicle, of course).

IF "YES", then I'm good to go - I'll just chalk it up as cost of ownership. (provided that the test drive truly impresses me).

IF "NO", then my current smile maker is MY BABY!

I guess I just don't like being put in the position of NOT KNOWING!!! I LOVE to drive and explore, and the Corvette is my chosen partner in that. Until I started my ZO6 research and found out how naive it is to be "brand loyal". I EVEN HATE SAYING THAT!!

My concept was that the ZO6 was a high performance, trustworthy "cruiser" (around town) and more than capable of anything else I asked (SANELY) of it......................................

What does the C6 Racing Team run for power - LS3 or LS7?

Thanks again for all your information & understanding - as well as sharing of personal experiences!! Through sharing we ALL grow!!!

(THIS is the best "institution" Mother ever put me in!!)

[Unreal]

Corvette racing team runs a 5.5L totally built crazy race motor. There is very little to no crossover to either street engine.

A ls3 vette is a much better cruiser than a z06. Don't forget the clutch problems and other issues z06s have compared to a base model. If you want a track car the z06 is a great starting platform. You would still need to dump 8-10k into upgrades for brakes, suspension, oiling system, heads, etc to make it a solid reliable track car.

Explain why you want a z06? More power? Well intake/tune/headers on an ls3 should bring it up into the 430-440rwhp range which is what a stock z06 does. Better handling? Add sway bars and shocks to your car and it will ride better and handle better than a stock z06. Better brakes? Stoptech, Brembo, etc all have brakes that are far superior to stock z06 brakes. Better looks? Adding a wide body kit to your current vette isn't hard at all.

[Drewstein]

Nick has a good point. If you already have a LS3, the cost of getting into a Z may be higher than just upgrading to your needs.

To answer your question, I would completely trust a Z with WCCH heads. Look how many of our members race the hell out of theirs with little issue. All cars will have maintenance over time and the Z won't be anything out of ordinary.

[Unreal]

I think a lot of people want a Z for ego stroking reasons, not performance reasons. That is fine, just say you want a Z so at car shows/meets you can tell people you have a Z. That is a perfectly valid reason to get one.

[Drewstein]

I think a lot of people want a Z for ego stroking reasons, not performance reasons. That is fine, just say you want a Z so at car shows/meets you can tell people you have a Z. That is a perfectly valid reason to get one.

No offence but most Z owners fall into that. At least the ones that frequent CF lol.

The owners that want it for its performance seem to be a smaller group for sure.

[ChadC]

I think a lot of people want a Z for ego stroking reasons, not performance reasons. That is fine, just say you want a Z so at car shows/meets you can tell people you have a Z. That is a perfectly valid reason to get one.

No offence but most Z owners fall into that. At least the ones that frequent CF lol.

The owners that want it for its performance seem to be a smaller group for sure.

I agree with Drew there are some seriously snobby Z06 owners on Corvette Forum.

I think once the c7 is out for 12 months and that crowd moves on to the next shiny "look at me thing" the "Drive-them-like-a-Raped-ape-with-AIDS-on-meth" crowd will come into bloom for the c6Z06.

[NDAGRUV]

My reason for wanting a ZO6 was/is that I believed that it was a step up (in all respects) over the other Corvettes (ZR1 excluded). I was under the impression it had more power (does till it BLOWS!), I definitely like the looks/exterior "balance" of the car, HOPED it was a "comfortable cruiser & canyon carver" (?). I also realize that the Grand Sport has several of the attributes of the ZO6, but for some strange reason I don't care for the two gills and lack of a rear brake air intake scoop. Go figure(?)

I DO NOT buy cars to please "others" (or "make up" for inadequacies), I do it just to please myself.

I've been building customs, street rods, low riders, etc., all my life - not on a professional level, just to be certain that I was enjoying "whatever" I was driving. Even won a couple First Place awards at the Grand National Roadster Show for "BEST FULL CUSTOM", two years running.

However, it is rewarding to see people slowing down on the highway, SMILING (versus being grumpy), giving you a thumbs up........ That pleases me to see others smiling and enjoying the "hot rod" that they're going by. PLUS, I enjoy driving "it" - what else can a guy ask for??? HAPPY ALL AROUND!!!!

I had assumed the ZO6 to be a Vette that gives good performance, and to tell you the truth it really bums me out that chevrolet is shooting themselves in the foot by not caring about their customer & standing behind their product. After all, they've known about this problem since 2005 (at least!)

If I had to say right now which way to go - I would probably stay with my Black & beautiful C6 LS3!! SHE'S SWEET, but then I AM prejudice!!

(How much does it cost to go "wide body??)

Muchas Gracias!

[old yeller]

I saw a certain lemans blue '06 Z-06 for sale the other day. Nitrous, roll-bar etc., etc.,................45k for it.

[Unreal]

Just don't the rears is $2-3k, with most of the expense being wheels since you need wider wheels/tires if you want to fill out the rear fenders. You could run spacers to keep the cost down. You can get prepainted RPI rear fenders for $1699.

http://rpidesigns.com/shop/item.aspx?itemid=1919

Front depends if you want fiberglass or real OEM carbon. The OEM fenders aren't cheap. Most people just do a widebody rear which looks great.

Don't get me wrong, a z06 is faster, it does handle better, it does brake better, but at a sacrifice. Added maintenance cost, added tire cost, rougher ride, noisier interior, questionable reliability, etc. Since you have a nice ls3 vette just add intake/headers/tune and you will have the power and IMO more reliability. Then add sways/shocks and you will have the handling. Then add the wide body rear if you want the looks.

[P51tj]

I saw a certain lemans blue '06 Z-06 for sale the other day. Nitrous, roll-bar etc., etc.,................45k for it.

WOW, wonder what's next???

[Unreal]

Now buying stegs car is a good deal. Everything is done, and it is ready to run. Heads done, tasteful mods, very clean car.

[ChadC]

Now buying stegs car is a good deal. Everything is done, and it is ready to run. Heads done, tasteful mods, very clean car.

yea but it smells like an asshole inside.

[theChad]