z0sicktanner

Yes you sure did get hell for it. thats why I said you was a stand up honest vendor. I had your back though not that it helped much. glad your back bro

z0sicktanner

97Black

Les

Just a quick update. I picked up the car this morning. Rich and his crew only needed it for about 2 work days, and that includes sending the heads out to a specialty shop where they assemble them and mate the valves to the seats. It was ready yesterday morning but I couldn't travel until today. I feel sorry for the folks who have their car hung up, sometimes for many weeks, at a dealership for the same work or less. The process for giving the car to them and getting it back was streamlined and seamless. If not for talking to Rich for a few minutes today, I would have been driving away in 5-10 minutes max, including the return of the rental car. By the way, his Z06 was on a lift getting prepped for his autocross season- sweeeet ride! I saw some aftermarket suspension bits, which will be joined by more soon, and some tires that probably shouldn't be used on the street.

I won't throw out any numbers here because Rich gave me only a ballpark idea. He didn't have the final paperwork with him (my paperwork just had a bunch of zeros on it), but I'll just say that the GMPP extended warranty has paid for itself by a ton. In addition to the heads, I did have the oil pan gasket replaced under warranty too. The car actually made it all the way home without dropping a valve or developing a noisy valve train. Just lucky I guess. It runs great and hopefully it will do so for a very long time.

Rich, thanks again to you and your crew. We're lucky to have you guys here in NorCal.

jedblanks

A valve may not break because it is .0050, but mine at about that clearance sure looked like someone was at them with a cutting torch near the base of the guide. And you could feel the wear on the valve.


On the plus side, I have a nice arrangement for next valentines day

Les

Jed, those pics didn't work for me but I would like to see them. FYI, Rich said that the shop that they use mics the valves at top, center, and bottom in relation to the guide- they are actually marked while within the guide to make sure they measure the right spots. In all the LS7s they've replaced heads on, they have found only 1 valve that was out of spec- by .0002 IIRC. Piecing together a couple of conversations, it sounds to me like the valves are harder than the guides and therefore they don't tend to take the hit as much. I wish I could have a few minutes with the guy at that shop to pick his brain.

2k Cobra

Glad things worked out for you Les!

What a shop.

z0sicktanner

let me get this right, he says they have only found one valve out of spec? his car dropped a valve toasted the block and your guides were toast? just don't sound right. I mean you No disrespect Les but I'm sure you can understand my point

Les

Thanks John.
I take no offense to what you said. I don't have all the answers by any stretch, nor have I ever claimed to. I can only try to put out things as I hear them. It's up to you, and anybody else who's interested, to decide what they believe. Your vids opened my eyes and, in fact, I think I stood up for you once when the chit started to fly.

I can say this- I made a living for almost 30 years figuring out who was lying and who was telling the truth. I got pretty good at it. I've seen or heard nothing from Rich that would cause me the least bit of concern about anything he's said. I'm doing the best I can to relay whatever I think might help others here. Anybody who has the proof of what the problem is- please stop holding back and put it out here for all of us. So far that hasn't happened. Rich doesn't claim to know what the source of the problem is and I believe him. I also have a hard time picturing why he would tell me my valves are good when they aren't. If he was motivated by money, he'd be able to make more of it by adding the cost of new valves to the warranty claim. Then there's the problem of hurting his reputation and that of Abel Chevrolet by putting out a product (work) that could come back to haunt him if the parts fail. That just doesn't make sense to me.

z0sicktanner

Les all I can tell you for sure is they have been using the same guides from 97-13 on all ls based heads and they never had an issue with the ss valves what changed? in 02 they used the sodium filled hollow valve in the ls6 that engine didn't have the problem. all of a sudden the ls7 is wearing guides and dropping valves. it's from heat Les please ppl got understand this. I know what I'm looking at I've been doing this for a long time. why did Rich put ss valves in his car? or better yet use used valves in his car? I'm not saying he isn't trying to help he is, and the only dealer I know of thats ever even heard of it before. You should be fine though because the valve shouldn't break with in spec guides. only one has been posted. I would check them again at 15k again Les Please take No offence not trying to upset anyone.

Mopar Jimmy

Les,

Great news, and man you are lucky to have the services of Richie Rich and his dealership (Abel Chevrolet) at your services.

Best of luck with your fixed heads.

I think maybe part of the confusion with Z06tanner's statement is the difference between a valve being out of spec. and the valve guides (which is 2 different things, right?) I don't know, just taking a wild shot in dark regarding what the confusion might be here, but sure wish Abel Chevrolet was in driving distance from me (for future warrany work as I have 2.5 years left on my GMPP on my 2006 Z).

z0sicktanner

I took it as wear on the valve from cooked oil.

1981turbota

Congratulations!! It's a nice feeling isn't it?

NotAnExpert

Corvette noob here

Is there a test to know if my engine is running in harmony? I am a perfectionist and would like to knowIif the internals are slightly off. What is the official name of a test that tests cylinder by cylinder to tell you if compression, lift, or other internal functions are out of place

For reference I have a 2002 base model.

Thanks for the post. It helped to get me to think about engine internal performance.

Mark2009

I measured eight used valves and didn't find any "out of spec" as far as diameter goes. Of course many of them showed galling on the lower portion of the stem which made them worthless, but the diameter was okay. The heads those valves came out of had lower guide wear in the double digits.

I will say that I wouldn't reuse an LS7 exhaust valve based on micrometer measurements alone... I'd want some high magnification examination of the stem for galling.

As someone else noted, the guides are wearing out, not the valve stems (other than being abused), so maybe we have a terminology misunderstanding.

The photo jedblanks posted (below) didn't look all that bad to me, compared to some I've seen... the guides were clearly not worn badly enough to let soot get up inside the guide, which probably leads to the galling (soot or coked oil or whatever).

'06 Quicksilver Z06

I know that you have one set of valves which came from out of a set of heads which had lower guide wear into the triple digits in half of the exhaust guides.

But to your part in red above, interesting, and I wonder if any such examination is being done before those who are reusing these exhaust valves in new heads, decide to use them.

track junkie

I agree. I inspected my replaced 6000 mile Ls7 exhaust valves with my stereo microscope and noticed galling damage.
My dealer Corvette service specialist thought they were fine initially and could be reused, I couldn't see the galling either without the microsope, with the microsope the damage looked like flaking chrome plating.
I went with new exhaust valves on my rebuilt cylinder heads.

Mark2009

There are two:

1. Compression test. A pressure gauge is connected to each cylinder's spark plug hole in turn and the engine is cranked over a few times. This will give a general indication of the condition of the rings and cylinder walls.

2. Leak down test. Again a pressure gauge is connected to each cylinder's spark plug hole, but this time air pressure is fed in externally and the engine is not cranked over. How much air leaks out determines condition of rings and wall as well as valves (sealing).

Pretty much any shop should be able to do both tests.

Neither will determine camshaft condition (lift) or guide wear (unless perhaps you have a leaky valve). Note that I am not an expert or professional mechanic so details could be lacking or overlooked, and there may be other tests available (fuel pressure, for one).

A chassis dyno test can tell you a lot as long as the dyno operator is monitoring live data (knock retard, timing, air fuel ratio, etc).

Also the science of 'reading' spark plugs is almost an art; experienced pros can tell you a lot about an engine just by looking at the plugs.

'06 Quicksilver Z06

Wow. Just think those valves could very easily have ended up in your new set of heads.

MTIRC6Z

I found it most interesting that Rich said the reason he ended up with ss valves in his heads was due to a misunderstanding, he did NOT want them and will be replacing them shortly...speaks volumes to me, but then that's only because I have a great deal of respect for Rich.

Cheers, Paul.