I really do not know how many CHE valve guide/Solid SS valve setups we have done, but its been a lot, not including my own personal c6 z... we have not had one valvetrain instability issue or RPMing issue... My own personal (well my close friend bought it) c6 z runs a .661 lift cam with an aggressive Ramp rate on lobe, with the appropiate setup dual spring. It revs to 7400 rpm clean, has 20+ tracks days on it, and while making 640 rwhp! There is a lot of naysayers on here with he said/ she said data, and frankly unless you do this for a leaving and have seen things with your own two eyes, please stop trying to disprove things with pure speculation. The solid ss valve method may seem crude, but the results speak for themselves. This method flatout keeps these motors alive under abuse.

Quick, thanks for posting that link -- lots of great technical info there, and a bonus link inside to a Car Craft article on lifter pump up! :cheers:

I'm sorry Mark, if I don"t get right back to you, Ryne was saying something important. Go ahead Ryne.

Wow, those are impressive results, and that is very sound advice, and apparently true, because of the success that we are seeing now. :thumbs::cheers:
There are several of your own customers out there who have these setups, and each time you do one, your reputation is on the line.

I've said this before, you guys who put food on your tables, and clothes on your kids backs, have a lot to lose if these setups don't work.

As such, I certainly trust your judgement when it comes to this matter.

I am running this setup in my own car, and have the utmost confidence in it.

As you know, we have run the full gamut here. From it's a geometry problem, and the development of a "tool" to determine if one has bad geometry. All the way up to that bastion of scientific research when it comes to this matter, the vaunted "wiggle test".

Oh snap, I'm sorry Mark, go ahead, what were you saying??

Yeah, yeah, yeah, any time, Mark, any time. Go and have fun with that.

I'm not sure which "RPMing issue" you're speaking of... if it's the slow revving issue, then nobody really takes that seriously -- it's just something the solid stainless fanboys dredge up to justify their illogical arguments. If it's the max RPM issue, well then I don't think any hands on training is needed to understand the laws of physics.

Or perhaps those laws are just pure speculation http://i1114.photobucket.com/albums/...lies/shrug.gif

In any case, I think everyone gets it -- solid stem stainless valves are building up a good track record in the LS7, despite being a pretty radical departure from the OEM design on several fronts. There are not really any engineering tests to determine how well they are working, but they seem to be making good power up to redline without breaking anything. In some circles, that is considered an unqualified success. Congratulations :thumbs:

I understand, Quick... if it weren't for others saying things, you wouldn't have anything to repeat (often, it seems, incorrectly) :lol:

Learning, instead of parroting, you mean. Yes, I enjoy learning. :thumbs:

Funny enough, my builder/tuner said something very similar. When I brought up a lot of this stuff, including the valve weights, he called the forums 'dangerous' and instead of worrying about I read on the internet, he recommended that I listen to the advice of people who do this stuff all day, every day.

Then when I spoke to WCCH not long after, they hands down recommended SS valves over both OE and Ti valves.

Two experts with two very strong recommendations for SS valves. I was previously torn on using the lighter Ti valves but it was pretty clear to me what to do after that.

Engine acceleration rate can only be quantified with any sort of reliable information on an engine dyno. I would be amazed to see a noteworthy % rate of change with a slightly heavier valve, correct springs and the same camshaft. Swap the cam and that’s a whole different ball game, but more is at play that “just” valve motion when you make those changes. You’d see more of a change in acceleration rate with a different flywheel than just swapping valves. That has not been my argument. My argument is peak RPM. Not fuel cut off rev limited peak RPM, but what the engine can safely spin up to without putting the valve train into the territory of instability. I do not know what the peak RPM is when moving to a heavier valve in this engine, and not getting too crazy with cam profiles and aggressive springs. Until some data can be collected, it is anyone’s guess. About the only thing you can go off of are success stories from others.

Have you ever missed an up shift to second or third at WOT and pegged the fuel cut off?? If so, what RPM did the engine reach?? If it did not climb past 7300 or so, you’re probably OK with your set up. I have seen 7600 before “with my own two eyes”, and that was with the stock fuel cut off settings. That was with an aftermarket cam and springs though.

I don’t do C6 cam swaps or tune cars for a living, so I reckon I better just STFU now. I have no f’ing idea what it is I’m talking about. I have a plane to catch anyway.

Quick, surely you know the problem with pretending to be dumb, don't you?

Interesting... that's what GM said in the latest TSB on the issue. That means there is no valve guide / valve problem at all, right? :lol:

You know, when I think of you being forced to say this above, I recall the story of the dog who swallowed a peach pit from a "green" Georgia peach.

It looked a little something like this:

http://2012photoaday.wordpress.com/2...roject365-219/
http://img.photobucket.com/albums/v3...ps58b41ca6.jpg

Well, the time came, when that peach seed had to be eliminated, and unfortunately for the canine, and as fate would have it, the peach pit, well, it took a sideways orientation at the last minute and at the last few inches prior to it's exit. :sad:

Tears streamed from the creature's eyes as he "worked".

I don't know why I thought of that story, when I read what you had to say above, and where you are now forced to admit:

.:D:rofl:

Congrats Howie - that's gotta be satisfying !

Thanks for the post and thanks Quick for posting the links.

Btw, I'll be going the WCCH route as well, but does anyone know of a Shop
with Cunningham Motorsports' level of expertise in North Florida ?? Thanks -

I don't understand why you lie about other people. I really don't. I don't think it impresses anyone, and if it does they would certainly not be the type of people I would want to impress.

Your mileage may vary http://i1114.photobucket.com/albums/...lies/shrug.gif

:lol: Good point.

However, GM clearly has an ulterior motive behind their statement. They don't want to pay up.

While folks like my builder and WCCH don't care which valve I use. They make money on the service, not the parts they're recommending. They were willing to go with whatever valve I wanted, but when I asked them for a recommendation, it was quite clear SS was their preference.

When you can't dispute and refute that which is being said, then call it "lies".

Interesting approach Mark. :lol:

You bring up multiple good points.

The people doing your heads, are going to get paid no matter which valve option you choose.

In fact, they would have gotten paid more had they let you go ahead with, or talked you into, Ti/Mo exhaust valves, but they didn't.

GM OTOH, like you say, has a different motive.

i sense your sarcasm, but what is your better idea to solve the problem? Everytime we do a guide and solid ss valve upgrade (using the appropiate spring of course) these cars just rev and run without issue, without breakng the bank for the customers......

I dont know how close you are to Redline Motorsports, but Howard and Jay over there can easily take care of you.

Thank you Ryne !

Thanks Ricky, I really appreciate that :thumbs:

:cheers:
DH

1. What is the problem? Specifically. Are the OEM guides defective or incorrect for the application, are the OEM valves defective or incorrect for the application, or is it an assembly/machining/manufacturing/QC issue rather than the fault of any particular part or the design of any particular part?

2. Have you done a guide upgrade only? (retaining OEM exhaust valves). What is your opinion on the OEM exhaust valve? Is it safe?

3. This one is open to anyone that does heads for a living -- is there any downside regarding combustion chamber temps when exchanging the hollow sodium valve for a solid stem valve? If not, why in the world are the GM engineers specifying a sodium valve, which is designed to transfer more heat out of the combustion chamber than a non-sodium valve (solid or hollow)?

Bill

I gave him a point by on the inside. I don't remember exactly what that car had but you can see that it was race prepped with wing, suspension and tires. Plus you could see the way he pulled that it was not a stock motored BMW :willy:

Usually I catch all those guys on the long straight and I can hold 130mph thru the NASCAR turn. But the wind which has never been a factor there destroyed my confidence at end of straight and the whole Nacar turn. There were many guys (obviously this one too) who didn't seem to be bothered by the wind at all. My best time was in the next session (2nd video) and even that was 1.5 seconds off my PB :ack:

:cheers:
DH