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C6 Corvette ZR1 & Z06General info about GM’s Corvette Supercar, LS9 Corvette Technical Info, Performance Upgrades, Suspension Setup for Street or Track
I agree, skip those. I think you will be fine with AHP PM guides and the PSI 1511 springs and Ti retainers and the rest you last discussed.
I read where top NASCAR teams use MS90 guides in their engines and I like that, but my goals are not exactly the same as a NASCAR engine builder - I just want to ensure that my engine doesn't drop a valve and I'm more than satisified with the highest lift camshaft (.591/.591) on a production GM engine.
AHP's proprietary PM guides are as strong (on the hardness scale that I believe AHP provided,) but don't quite have as high of thermal conductivity as the MS90 guides. From what I'm gathering, AHP's PM guides are probably just fine (if not ideal) for a stock setup?
Last edited by BigVette427; 12-31-2016 at 11:34 PM.
All the LS7 head issue news will undoubtedly hurt the resale value of our Z06's as they get up in mileage. One of the reasons I jumped in and replaced my heads on my low mileage Vette was to enhance its resale value as I have been looking to replace it with a 2010ish ZR1.
****, now I'm hearing the ZR1 LS9 is demonstrating similar premature valve guide wear issues. From what I am reading at least ZR1 reported problems have not yet resulted in destroyed motors. Here we go again?
GM's rumored DOHC engine is sounding better all the time.
All the LS7 head issue news will undoubtedly hurt the resale value of our Z06's as they get up in mileage. One of the reasons I jumped in and replaced my heads on my low mileage Vette was to enhance its resale value as I have been looking to replace it with a 2010ish ZR1.
****, now I'm hearing the ZR1 LS9 is demonstrating similar premature valve guide wear issues. From what I am reading at least ZR1 reported problems have not yet resulted in destroyed motors. Here we go again?
GM's rumored DOHC engine is sounding better all the time.
I think what will eventually happen here is that you will HAVE to have the documentation to show that some sort of head correction was done on an LS7 motor to maintain its value to the informed...there are lot of folks that are uninformed outside of the vette community. Pretty much the LS7 motor is good to go after the head fix. Longevity/maintenance is no different than ANY other very high performance engine that gets high performance wear. Folks I know with high mileage 911's or rarer cars like Ferrari all have motor work once the mileage starts climbing in the higher double digits....
I read where top NASCAR teams use MS90 guides in their engines and I like that, but my goals are not exactly the same as a NASCAR engine builder - I just want to ensure that my engine doesn't drop a valve and I'm more than satisified with the highest lift camshaft (.591/.591) on a production GM engine.
AHP's proprietary PM guides are as strong (on the hardness scale that I believe AHP provided,) but don't quite have as high of thermal conductivity as the MS90 guides. From what I'm gathering, AHP's PM guides are probably just fine (if not ideal) for a stock setup?
Correct you cant go wrong with either our PM guides or our Moldstar90 guides, they are both top tier guides!!!
We enjoy answering questions about our heads so if you have any you can always give us a call:
310-326-2399
or shoot us an email: HP@americanheritageperformance.com
Correct you cant go wrong with either our PM guides or our Moldstar90 guides, they are both top tier guides!!!
We enjoy answering questions about our heads so if you have any you can always give us a call:
310-326-2399
or shoot us an email: HP@americanheritageperformance.com
Kohle, are you guys starting to see similar valve guide wear issues on LS9 heads like on ZR1's?
LSA, Ls3 and ls9 also have valve guide wear issues. They just don't run a thin wall 2 piece valve that likes to break apart as easy, even though it does happen. My friends bone stock zl1 camaro dropped an exhaust valve
Guides wear. They are a wear part, and to expect otherwise defies logic. Even fancy high dollar ones.
If staying stock, don't mess with roller tips or use heavier valves. Just get the guides worked and seats recut. The PSI spring is a much better spring than the OEM spring and a solid option with zero downside.
Kohle, are you guys starting to see similar valve guide wear issues on LS9 heads like on ZR1's?
We do rework quite a few LSA and some LS9 Heads. We have seen some guide wear issues on the Zr1's but nothing like the Z06's.
The 1.7 ratio rocker on the LS9 is more forgiving to improper valve train geometry than the LS7's 1.8 ratio rockers.
We do rework quite a few LSA and some LS9 Heads. We have seen some guide wear issues on the Zr1's but nothing like the Z06's.
The 1.7 ratio rocker on the LS9 is more forgiving to improper valve train geometry than the LS7's 1.8 ratio rockers.
That's an interesting point that I was wondering about, the 1.8 rocker ratio was one of the LS7 features that carried forward into the GEN V motors. Do the 1.8 ratio rocker in the GEN V motors like the LT1 and LT4 lend an increased propensity of premature guide wear? LT1 has a fairly stout camshaft with .561"/.531" lift, and the LT4 has a camshaft with a .492"/.551" lift. A lot of GM trucks out there running L86 V8's which are essentially LT1's in truck form.
Last edited by BigVette427; 01-06-2017 at 09:21 AM.
First post. Just bought a 07 z06 with 14500 miles. Want to get the valves issue resolved. No problems with the car right now. Just don't trust it. Called And spoke to Dave at WCCH. Told me they would install SS exhaust valves, new bronze guides, polish intake valves, and new springs. Does that sound about right. Car will never see any real rough use.
Last edited by Waynz06; 05-02-2017 at 07:33 PM.
Reason: Wrong name
First post. Just bought a 07 z06 with 14500 miles. Want to get the valves issue resolved. No problems with the car right now. Just don't trust it. Called And spoke to Dave at WCCH. Told me they would install SS exhaust valves, new bronze guides, polish intake valves, and new springs. Does that sound about right. Car will never see any real rough use.
That will get the job done. Many, many folks on here running WCCH reworked heads on their LS7. I chose a slightly different route (AHP) for different reasons, but WCCH has a stellar reputation.
I just completed my head swap earlier this week on my 2008 Z06. After numerous discussions with Kohle at AHP and Rich at Abel Chevrolet I went with this. My Z06 is otherwise bone stock and is not tracked. It does see occasional spirited driving at 6,500 RPM shift points max. For my needs I believe this combination will be fine and cost effective:
I'm in the middle of my head swap also using AHP package 4, but opted for porting and .020 milled head and shorter pushrods. just need to clean the decks and I hope my heads will be delivered soon. I also have B&B headers on the way.
Last edited by itomh; 05-08-2017 at 10:03 AM.
Reason: Fix
12-31-2016, 11:22 PM
