Katech_Zach

This is my personal car. 23,000 miles with about 10 hours of light HPDE use. It's not the worst we've seen but I don't like the taper. As I have said in previous posts, GM states the problem is 2009-2011 but I'm not so sure. We recently had a 2007 that was very worn.

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FNBADAZ06

How much of that 23,000 miles was spent with the Torquer cam installed ?

Katech_Zach

20,000

FSTFRC

Jason,

Are your heads modified or stock? Which guides do you have in the heads?

Thanks...

Katech_Zach

Stock valves
Stock guides
PSI springs
Katech Ti retainers
WCCH ported
Decked .030"

FNBADAZ06

Stock rockers with a trunion kit, and E85 as well...correct ?
Can't remember, but was the head work done at the same time the cam went in ?

Katech_Zach

Completely stock rocker arms. Heads were ported at about 15,000 miles.

FSTFRC

Make I ask what our your plans now that you have this information? (in the first post)

thanks....

Achilles97

Thank you for the information.

Were your heads ported by WCCH and they installed new OEM valves and guides? Or, did they reinstall your stock valves and guides?

When I got my heads done, I considered getting ported heads with OEM valves and guides. My thinking was that the problem was the factory geometry, and a re-installation of OEM guides and valves by a good shop would correct the problem. Maybe it's not as clear-cut a situation as I had been thinking.

Thanks!

Michael_D

Did WCCH work the seats as well as the port work?

Katech_Zach

The car is sold. I'm just rebuilding the engine for the buyer. It will either be new OEM guides and OEM valves, or bronze guides with Katech Ti/Mo valves. It depends on what the buyer wants.


It was porting only. Guides and valves were not touched.

Katech_Zach

No


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Achilles97

OK thanks. I assumed that porting required the removal and reinstallation of the guides and valves. My mistake.

jimman

Engineer from Florida found some dimension issues causing valve stem side loading, do you know if that was checked?

Vette @ 71

Are these results of a wiggle test with gauge or actual bore measurements??

If wiggle testing , any plan to make actual bore measurements to confirm / validate/ calibrate actual wear vs wiggle methodology.
Thanks for info.

NEVERL8

Do you think using an ester based motor oil, like Red Line, would have mitigated some/most of the wear issues versus using the factory fill Mobil?

Michael_D

I think you have your answer then........ I think Dennis Wheet has a jig of sorts for checking run out on worn LS7 heads. Might be worth a phone call to see how he has been doing that.

Katech_Zach

Bore measurements.

Katech_Zach

I think if there is a machining issue from the factory the oil has no part in it.

GMuffley

Thanks for posting. The more info out there, the better everyone is in terms of making an informed decision.