musicmankeb

I'd just like to say that after talking with many large vendors, cylinder shops, small vendors, and large companies, there are many different opinions on what the valve train problem is and solutions.

I've heard everything from:

Replacing the guides with OEM guides if the original are worn and also replacing the exhaust valves with OEM if worn. (big company/vendor)

Replacing guides with bronze guides and replacing the exhaust valves with OEM if worn (which keep in mind are softer and will wear out faster) (another big company/vendor)

Replacing the exhaust valves with solid SS valves and replacing the guides if needed with bronze (several well known vendors and cylinder shops)

Most would agree that replacing the springs is a very good idea with an aftermarket set and is pretty much required if you are going to do a head/cam package.

So I honestly have not come to a conclusion to what the real problem/fix is for the LS7 motor and or the LS9 as well but I just wanted to share my experiences. I also want to say that it is my opinion that this seems to happen to cars that are tracked and ran hard but some were not and some barely had miles on them. That's what scares me.

With that said and in my opinion once again, I really would like to see this issue addressed and solved/explained thoroughly. I'm sure everyone else would as well.

That is all!

Prime Target

Somebody shoot me please....

Bill Dearborn

Being one of the people who lost a stock engine due to the head of the exhaust valve falling off I would like to see a solution as well. I would really like to know whether the new engine (built in May of 2011) GM installed has updates that fix the problem.

However, I doubt we will ever know if the problem is resolved or the resolutions proposed by the engine builders work since they just haven't seen enough failures or attempted enough fixes to really determine what works. A large percentage of these engines were warrantied by GM so they were sent back to GM and there is no word on the cause of the failure or resolution of failure. That leaves the few seen by the engine builders who like the engines that failed are scattered across the country with no easy way to compare what they saw and what they did to fix the problem.

Bill

3 Z06ZR1

With some ls-7's hitting over 100k. Mine has over 40k without an issue.
I think oil cokeing/cooking on the Valve stems and wearing the guides and causing issues seems possible. Another reason maybe for not doing extended oil changes. Some just run them much harder than others!
I'm not having any issues!

LS9Drew

What springs would you even run on a stock cam car? Kind of odd

'06 Quicksilver Z06

Once you get past 2008 models, reports of valve issues in later year model LS7 engines diminish.

2006 production 6,272 cars.

2009 production 3,461
2010 production 518
2011 production 904
2012 production 478

Total 5,361 cars built during the 2009-2012 model year with the first of the 2009s being released in summer of 2008, some 4 years ago, and one report of valve issue in here (broken valve spring) in a stock car.

You have those who like to say that valve issues still exists in cars built beyond 2008.

But ask them to post up an example of a stock post 2008 LS7 engine failure, and they can't.

propain

Every shop I have ever been to says if the valves/springs/guides are worn just leave them alone and let the motor blow up and do a warranty replacement or hope it burns to the ground and get a new car.


Hmmmm.... So let me get this right, companies told you if the certain items in question are worn you should.... replace them?!?!?! Shocking!

Mopar Jimmy

: beatdeadhorse::beatdeadho rse::beatd eadhorse:: beatdeadhorse:

TapOut

Bwahahahhaaa! Ohh brother!! Please for the love of Jesus/Buddah/Allah/Spaghetti Monster....let this topic die!!!

Lawdogg

I plan to replace the valve guides and exhaust valves this coming winter (if motor lasts that long). That seems prudent on a car that sees track duty and is not under a warranty.

Dirty Howie

I would, but I already used it on myself


DH

GMuffley

What about the rest of us?

Dirty Howie

I'm logging my hours on this motor. But haven't decided if I will do maintenace work on the heads at some as of yet undetermined point, or if I will just run it and see if I can get past 87K and 30 track days.

Would be good data for Quick


DH

Dirty Howie

Come over and pull it out of my cold clenched fist


DH

musicmankeb

If you have no information then leave instead of being a d1ck. What I'm trying to say is it seems like there is no real solution to this problem. It's not like everyone recommends the same thing and it's because no one really knows what the problem is or they just won't tell anyone.

I'm putting information out there for people like me because I took the time to get a lot of opinions from different shops/vendors.

Also, in my opinion replacing the valve guides with bronze (softer) I don't think is a real good solution. Lets think about this, if your steel guides are being worn out and you replace them with new bronze guides which are softer how much time do you think you have till those wear out as well. Why not figure out the root cause and fix it....

'06 Quicksilver Z06

Yes 'twould, yes 'would.

Every day which goes by that we don't hear of "LS7 valve issues, is a good day.

Truth is, there were apparently some issues with the early LS7s, and there is evidence on this very forum to show that there was.

However there is NO evidence to show that there are issues with the later 2009 and up, versions of it.

And BTW, your running that new Mobil 1 oil you're using with more ZDDP than the 5w30, could also be a key factor in the evaluation of this "issue".

At any rate, a lot of you guys with engine replacements done after 2009, are still running strong, and you have not changed your driving habits.

I'm also encouraged by the guy with the 20 some odd thousand track miles, out of 30 some odd thousand total miles, over about 5 or 6 years. The only way he missed an HPDE was if they weren't having one due to rain. He was running Royal Purple before his engine finally gave up the ghost.
http://forums.corvetteforum.com/c6-z...post1580576962

Both you and Bill Dearborn are still driving just as hard as you ever did, as is Lawdogg, and you all seem to be doing fine.

Lawdogg

Root cause? How about guides that aren't long enough. At least that's what I've been told by some engine builders. According to them, the fix is longer guides and maybe getting rid of the two piece exhaust valves. I understand that Katech doesn't think the two piece valves are the problem and uses them in the engines it builds. Not sure about its opinion on guide length or guide material.

TapOut

I think the problem here is that you HAVEN'T taken time to investigate. If you do some actually searching and reading through TONS AND TONS of pages of info on the forum....you would have a better idea as to the problem.

I've said this to people like yourself a million times, and I'll say it again: Jason from Katech gave a nice long explanation of THEIR findings and what they recommend for what application you plan to run. The high level of it is that if you remain stock, you're perfectly fine. If you run a cam, you WILL have failure. If you're stock and still paranoid, then they have a recommendation for you there as well.

Remember, these are the people that originally worked with GM to develop the LSx based motors, so they know what they're talking about. Plus GM has A LOT more time, money and engineers designing this engine, and they have used certain components for a reason. Trust me, they know a lot more than a head shop that is just interested in selling their parts/services, and don't necessarily care or know much about how the entire package works together. So just slapping in some heavy SS valves might solve one issue, and cause 20 more.

All you can do is stop the speculations, look at the studies done by Katech and other shops, and choose which one feels right for you. There is no ONE answer, but there definitely are answers that are more reliable than others. What people are tired of hearing is people creating new threads everyday beating the same horse to death. Look up the facts and recommendations, and choose the one that has the most information and experience.


PS - You also have to take into consideration all the basic facts in life: Some engines will die for no reason (laws of physics and cost of mass manufacturing), Some are user error, Some are 07 needle bearing issue, and others are just plain old simple User error, and an engine living a short life due to being constantly raced. Oh and please don't use the, "Ohh I raced my Miata for years without any issues!" line. Higher HP motors will always have a higher maintenance and failure rate then lower HP motors.

LS9Drew

Richard at WCCH has plenty of experiences with heads so I wouldn't act like he just sells people crap and doesn't think anything out. Heads are what be does for a living if he did things like that why would almost every LSx shop recommend getting work done by him? Dude knows his stuff.

And SS valves have been used in LSx motors forever plenty of people run their other LS engines to 7k with them with 0 issue

Dirty Howie

All ture. But so far I only have a fraction of the total milage and track hours that I had on my first motor.

I do hope the Mobil 0w40, as well as better cooling with Finspeed oil cooler and Radiator add to this ones longevity


DH