MTIRC6Z

AGREED!

What I find truly sad is that the hype on this forum caused the OP to get rid of a good car which he obviously liked enough that he is still interested in owning something very similar.

I suspect the solution to his problem is to buy whatever he really wants, ensure it has a warranty and then STOP reading forum (or at least the engine failure threads) and instead just drive/enjoy the car.

Cheers, Paul.

Unreal

I don't agree that ignoring a problem is a good fix. Be educated on it, and do what makes you feel good. If driving a warrantied car is that, do that. If doing nothing and excepting a chance it could happen makes you happy, do that. If getting the heads works makes you sleep better, do that. Basically it is a choice for the car owner to make, but sticking your head in the ground and saying there is no problem is a bit silly in my opinion. Buy one, enjoy it, but be aware it could be an issue.

I haven't met a single owner that regrets getting the heads worked on. Everyone I've met and talked too was very happy they did it because of the excessive wear when the heads were removed. I'll keep recommend getting the heads checked for wear and getting new guides for now.

sshu

I wouldn't be worried about the valve or bearing issue since you are buying new and have a 5 year powertrain warranty. I would not do any mods on the car. GM supposedly corrected the issue by 2012 but nobody really knows. Since you are already have a C6 I would go for something different like a C7 vert or wait a year and get a C7 Z06

'06 Quicksilver Z06

You make some good points.

The engine failure reports made on this forum, undoubtedly include a few people who were guilty of doing exactly what you describe above in bold.

BigVette427

So what's the bottom line on an LS7 in a 2013 427 Vert?

First, I get a standard five year, 100k mile powertrain warranty that I would likely extend at purchase to at least 7 years, if not 10 years. (No way near 100k miles on this car for me in five years, maybe 10, but I doubt that as well.) I figure by that time with more and more examples, the problem should be readily identified and resolved.

So is the problem really sodium filled exhaust valves and/or powered metal guides? The LS9 and the LT1 both use them as well, so what gives? (And it doesn't sound like an inherent flaw of the design of the LS7 head.)
http://www.hotrod.com/feature_storie...e/viewall.html

At worst case while under warranty, the engine would grenade and be replaced (least desirable outcome.) Hopefully IF I did have an issue, it would become apparent enough (noise, oil on plugs, etc.) to have the heads replaced (under warranty) before that happened.

At which point I would entertain someone who knows what they are doing with LS7 heads (perhaps not GM,) rebuild with bronze valve guides and or solid stainless steel exhaust valves. A Corvette specialty shop in CA in this forum just posted special pricing for forum members on a complete rebuild of your LS7 heads, clean and re-surface, and install with the aforementioned parts for between $932 and $1,100, depending upon what specific parts you wanted to go with.

For a guy (or gal) who isn't really looking to "track" their ride, isn't that about as good (peace of mind) as one could hope to get? Surely by five, seven, or ten years (when my powertrain warranty expired on my '13 427,) the problem should be well documented, especially with all these new C7 LT1's and their similar valves and valve guides, right?

Bottom line for me, I love the looks of the wide-body C6 2013 427 convertible and it's round brake lights with 13.5" wide P335/25ZR20 Michelin PS2 ZP's in the rear! 7.0L dry sump motor, ZR1 spoiler, dual mode exhaust, magnetic ride control, carbon fiber fenders and raised hood with 427 emblems.

I've never really even been a big convertible guy, but throw that all in for the same price of a low-optioned 2LZ Z06 and I'm like well, how could I not?

adamgl

I agree, but I'd like the original cause of the wear to be found.

jedblanks

I'll See that and raise you "I'll never buy another chevrolet as long as I live"

The sticker on my 2007 was $75,000 and was likely bought at over MSRP. The stickers on the newer ones is higher. Had chevy handled this better, I would have a brand new chevy truck in my garage instead of a Nissan.

forg0tmypen

Link to claims? Theres been rumors. But nothing concrete. I have a 2013 LS7 in my Z06. It only has 5,000 miles, I will be getting the wiggle test done soon and posting the results.

Unreal

I agree too, but for now, until we get to that point I'll check them every 20k. So far my PRC heads are working great.

I have a forged LSX 1000+rwhp car. I'm going to be running SS or inconel valves no matter what because of the HP and heat. So far my setup has been fine.

LFZ

Contact your buddy Chad...he's down there in Florida near you IIRC.

forg0tmypen

I just spoke with his wife a few hours ago, he's going to call me back later today she said. Really want to get the wiggle test done with early miles as a baseline of sorts. He will pull the heads if excessive wear is found (doubtful at 5,000)

LFZ

Let us know what you find out...even at 5k miles, getting that info would be very beneificial.

forg0tmypen

If he does pull the heads I'm going to put it back to stock, it has a katech 116 and their springs/retainers in it.

Crossofiron

Some real rude folks on this forum.

Your question is legitimate .

The C7 has some real advantages over the C6 for sure.

Looks are subjective.

A base C7 will not out run a newer Z06/Z07.

You really cannot go wrong either way.

Both very good cars and loads of fun!

Crossofiron

How much are you paying for this test?

BigVette427

The LS9 in the ZR1 uses similar sodium filled exhaust valves with powered metal guides, as do all the new C7 LT1's, right? I've never heard of this issue with the LS3, and what about the LSA in the ZL1 and CTS-V? Have LSA's been dropping valves? All I can find info on the LSA valves are in reference to the intake valves.

The gatekeepers of the heads’ combustion chambers are large-diameter, 2.16-inch (55 mm) intake valves and 1.59-inch (40.4 mm) exhaust valves. The intake valves are made of steel and feature thick heads.http://media.gm.com/media/us/en/gm/n.../0208_lsa.html

Mark2009

Mark2009

If you don't do that test with a dial indicator then you stand a good chance of wasting your time and your money, or just winding up confused. FWIW . . . .

Mark2009

Sodium filled hollow stem exhaust valves are used in the LS6, LS7, LS9, and (C7) LT1. Not to mention other non-GM vehicles (2012+ Ford Boss 302 DOCH Laguna Seca, for one, and the 2013 Viper for another). All the GM vehicles use PM guides (unsure on the non-GM).

According to documents at GM Powertrain (.com) the LSA uses sodium valves from 2011 onwards. Prior to that is uncertain (earlier docs make no specific mention).

The LS3 used empty hollow intake valves and solid exhaust valves. The LS6 also used empty hollow intake valves.

TulsaVette

http://forums.corvetteforum.com/c6-z...nd-belief.html