LS7 Valve Issue - Fact or Folklore ?

[Manny@Dasilva]

For those that still think the LS7 valve issue isn't real , just look at these LS7 heads that came off of a 2010 Z06 with under 20,000k.

Every valve loose . We could actually hear the exhaust fluttering when it came in .



Dasilva Motorsports is your LS7 Cylinder specialist , we have replaced many of these heads on our exchange program .

Our replacement reworked heads consist of the following :
Hot tanked and cleaned
New bronze guides
SS Exhaust valves
Brain Tooley Double Spring kit
New GM Gaskets & Bolts
Fresh fluids ( Oil & Filter + Coolant )
Professionally installed

All for $2599.00 + GST
Port & Polish Extra
ARP studs or head bolts also an option.

Call today for apportionment .

 

[Riley P]

I've read up on this. Pretty scary stuff. Hey Manny, if I can't swing a C7 and have to "settle" for a C6Z, what would be the cost difference between getting the heads reworked or just buying aftermarket heads? Or, if there are too many variables to say, would it be worth upgrading to aftermarket heads? I can't believe gm let the improper machining of these heads go on so long.

 

[dankhts]

Manny is this problem evident only on certain year LS7 engines, or all years?

 

[Keith Tedford]

I've read several stories of the two piece valves breaking. That usually takes out a cylinder wall and messes up a head as well. Changing out the valves seems to be a good move too. A good rev limiter might be a good investment for the stick shift guys who THINK they know how to shift. It's not like GM has never built an engine before. Our old L72 427 Chevelle went close to 200k miles and saw a lot of 6500+ rpm shifts along the way. The odd missed shift too. So, what's the problem now? This is 44 years later and things are supposed to be getting better. Compared to the old days, these are race engines and do need the very best parts if they are to stay together long term. New ideas are not always better I guess. If you need to replace heads, there are some pretty nice CNC ported pieces available.

 

[Manny@Dasilva]

It seems to be very random as to which years have this problem . We have seen it on 06 through to 2013 cars .

A set of after market heads adds another $2000 to the cost , and you can get around $1000 for your LS7 heads , so its really only $1000 or so to go to the aftermarket heads .

 

[Somebuddy]

Would GM not cover this if the car was still on warranty? Wow having to do this kind of work on a vehicle with so few klm seems absurd.

 

[vettefan]

Would GM not cover this if the car was still on warranty? Wow having to do this kind of work on a vehicle with so few klm seems absurd.

Yep, covered under powertrain warranty.

 

[abeltrame]

Thats crazy. Paul sent me a pic of it. Very close call for sure.

 

[Keith Tedford]

What are they using for valve guide material? I dare say that oil soaked hardwood would last longer than that. Is this happening to any other LS engines? I hope not, although it would be a great opportunity to upgrade the engine.

 

[VelocityYellowRules!]

Gentlemen,

I had heard of this issue and it did make me nervous on getting an LS7.

Makes me oh so glad that Manny took a dekko at mine when the engine was exposed. Nothing says piece of mind like the Dasilva seal of approval!

Cheers,

Garry

 

[FordPrefect]

 

[VelocityYellowRules!]

Gee Manny finally hiring that extra staff to help out around the place??

Sort of looks like me about a year ago now that I think about it!

 

[Manny@Dasilva]

Gentlemen,

I had heard of this issue and it did make me nervous on getting an LS7.

Makes me oh so glad that Manny took a dekko at mine when the engine was exposed. Nothing says piece of mind like the Dasilva seal of approval!

Cheers,

Garry

Thanks Garry , really appreciate the kind words from a friend so far away

 

[Manny@Dasilva]

Waynner your the best buddy ....Love your sense of humoor

 

[Manny@Dasilva]

What are they using for valve guide material? I dare say that oil soaked hardwood would last longer than that. Is this happening to any other LS engines? I hope not, although it would be a great opportunity to upgrade the engine.

This issue is only on the LS7's , no need to worry Ted .

 

[Keith Tedford]

I'm glad to hear that Manny. What are the guides made of that they would wear out so fast? There are quite a few guide materials available today. That's pretty bad. It's beyond bad. Here is some valve and guide info I found.
Valve and Guide Material, Selection Update: Engine Builder

 

[buckhorn76]

i have heard that the cylinder head supplier had improperly machined the guides on some heads.

 

[Manny@Dasilva]

i have heard that the cylinder head supplier had improperly machined the guides on some heads.

This correct , its not the material the guides were made from but rather the machining process that was out of spec.

 

[Keith Tedford]

Now, that makes sense.

 

[Riley P]

Still pretty amazing that something out of spec could not be corrected over 7 years!!! If I do get a Z06, this upgrade will just have to factor into the cost....along with a cam, headers......and maybe a supercharger.