More bad guides *video inside*
 

I just shared this in another thread and I thought I would just put this here for everyone to see.

To start, I bought this car back in June (2013) from a good friend who bought the car brand new in '08. I knew every single thing done and who did the work. The work was done in '10 which at that time the shop had no idea about the valve guide issue. Even though they replaced the exhaust valves they did not replace the valve guides. The work that was done includes a cam, ported heads, ported intake, ported tb, dual springs, Ferrea exhaust valves, 160* thermostat, Long tubes, etc. All the things that go with doing a cam. These mods were done with about 2,500 miles on the car. The car now has 10,500 miles on it and I decided to pull the heads and have them checked just to be sure and I am glad I did! The car had shown no sign of the valve guides wearing that bad. No noticeable extra valve train noise, no smoke at start up, nothing! It was basically a ticking time bomb! I got lucky! After the heads were cleaned up, machined for new guides, and a valve job it cost me about $700. Thats a lot cheaper than a new motor. Pull the heads and have them checked. If nothing else just for your own peice of mind.

Heres the video. Hopefully the first one works if you click on the pic. If not there is a link to click on. Here it is:

http://i27.photobucket.com/albums/c1...ps8fe9282c.jpg

http://s27.photobucket.com/user/coxt...9282c.mp4.html

I just can't believe GM won't man up and fix this. :smash::crazy2:

This is reminiscent of Chad and what Richard showed me at WCCH.

:cheers:
DH

Thanks for posting this up, kind sir. :thumbs::cheers:

I noticed in the other gentleman's thread, that you posted up that to remedy this matter, you managed to re use your original Ferrea solid stemmed valves, and went with new guides.

A question if you don't mind.

We have heard tales and prospects of killer "valve bounce" with the use of heavier than stock exhaust valves.

If you were running solid stemmed Ferrea exhaust valves, presumably Ferrea Superalloy, as the new hybrid solid/hollow stemmed valve they use now was not available back in 2010 when the heads in your car were originally done, well then you were running one of the heaviest options out there in use when it comes to managing this problem.

You mention above that when your heads were removed and examined recently, that excessive wear of the stock guides was noted, and in your video you attempt to demonstrate such.

My question is; when the heads were removed and the Ferrea exhaust valves were examined, as they clearly must have been as you re used them, did anyone notice any tuliping or any other signs of "valve bounce" having affected these valves?

Thanks

Great question. Wasn't bounce supposed to destroy the valve seat and lifters :D

:cheers:
DH

That is a good question. I myself did not remove the heads or disassemble them. I don't have the means or tools to do that kind of job. I sent them to a trusted friend that runs a performance engine building shop. I'll forward your question to him and get back with some answers because now you have me curious as well. :thumbs:

Well first of all it was a pretty smart move on your part to look at this issue, address it and at least maybe avoid the dreaded $14000.00 fix. I'm still amazed at some folks who still think this problem is blown out of proportion. What exactly made you decide that you needed to look at this? There seems to be thousands of Z owners who haven't found this forum and still don't know this exists.:D

Well I have had a long running history of bad luck when it comes to modded cars. My last C5 was a nightmare and my TA before that wasnt great either haha. When it came to this car I didn't want to take any chances whatsoever. Ragin' Racin' is who did the work and as we know they're a very reputable shop. I had actually called and spoke with Randy and he warned me when I was asking a few details about the build.

He said "Now, when we ported the heads and did the new valves on that car, the valve guides weren't an issue at that time. Not many people knew about them then." So I asked, "So bascially your telling me I have a ticking timebomb?" And he said "That's exactly what I'm telling you."

Now I had read all the warning signs on the forums here, but nothing put the fear of God in me than to hear Randy say those words.
I can make the car payment but I can't afford to put a whole new engine in it if this one were to let go. I couldn't justify paying for a $50,000 car to just sit with a blown motor.

Glad you caught this before it became a problem!

'06 Quicksilver Z06,
To your question about valve bounce. I forwarded your question to my builder and this was his reply:

"I saw no signs of "valve bounce". The installed heights were uniform and in spec. When I refaced the valves the seat angle was correct and NOT beat out. The seats on the heads looked fine to. I would be interested in seeing what springs others were using and how they were installed to create a "valve bounce" situation."

I hope this information helps.

Well I don't know Randy, but my hat is off to him, as he must be a stand up guy to come out and let you know that.

Kudos Randy. :thumbs:

At any rate, glad you got the matter managed now JCox23 for the reasons you already state.

It is a huge help JCox23.

If your valves are Ferrea superalloys then they weigh in at over 100 grams.

That you went for so many miles and on grossly out of spec guides for a portion of that, with no signs of valve bounce, is yet another piece of the puzzle for those who have followed this matter, discussions on it and management protocols for it.

Big thanks to you JCox23. :thumbs::cheers:

Good catch! Glad you checked before it was too late. When you machined the heads for new guides did you go powdered metal or bronze this time? On a side note and not to hijack-

I see you're in Garden City- do you know Zach Gigot?

X2 :rock:

Good to know.

I believe they're bronze.

And yes as a matter of fact I do know Zach. I have sold him Race fuel and talk to him here and there. :thumbs:

Which springs were you using and how were they setup?

Good call on the bronze (in my highly controversial opinion). I agree- it's pretty amazing there has been no formal acknowledgement by GM. You have reinforced my thoughts about doing the wiggle test on my H/C car at 10k.

I figured if you were into motorsports in Garden you'd know Zach & his family. I had a lot of good times with that guy at KSU. If I ever bring the Z out to KS it'd be cool to meet up and get a few shots :thumbs:

I believe they are Either PAC or Manley dual springs with titanium retainers. That's what they offer in their cam package but don't quote me on that as I don't have the receipt in front of me at the moment.

I'm down as long as I'm in town and not gone for a car event or something of that nature haha.

I may be mistaken but it seems you contradicted yourself there. You say there was no sign of wear that was bad. Everything checked out, but then you finished the next sentence with "it was a ticking time bomb."

Im confused.

I believe he meant that from the outside the car had no symptoms that would lead him to believe there was a problem. Upon inspection of the guides it was found that they were severely worn.