Michael_D

No I have not Paul. I hate the LS7 rocker set up though. I find it moronic that they are non-adjustable. I will most likely yank the heads again and run the Crower set up, if I get motivated, some day.

erikszr1

which one? lol

American Heritage

We currently do not offer this as an option but It may be available in the future

American Heritage

Yes you can send in you LS heads for any work. VJ, Milling, tested, porting, guide replacement, setup for T&D rockers or Jesel rocker arms, ect...

PM us for pricing or additional information

4wheels

I thought the pedestal height problem was released as TSB similar to the guide machining problem, but I could be wrong. However there was an acknowledgement from a GM rep and it's been documented in several threads on this & other forums that GM admitted to a "rocker arm mounting pedestal machining problem" that screwed up the rocker to valve tip geometry & resulted in accelerated wear. IIRC they were originally attributing the 2009-2011 failures to this, then subsequently released the valve guide machining TSB.

4wheels

The easiest way is to simply look at the contact patch & wear pattern on the valve tip & rocker pad. Unless the threads were closed or deleted there were previously several discussions how to measure this, but it all boiled down to on the heads with the "out of spec" pads, you could see the wear pattern was shifted off center.

Otherwise you need to setup the heads on a surface table & start comparing the pad heights to a golden sample or GM dwg and I don't remember what that dim is supposed to be off the top of my head.

Mark2009

The pedestal theory was advanced by a forum member who was eventually badgered off the forum by the usual suspect(s). The theory was never proven and no GM reps were involved (unless you include me, as I have been accused by the same suspect(s) of being a GM 'plant' or operative or current/former employee). The bottom line was that it was possible that the worn guides could have caused the abnormal wear pattern on the rocker tips, just as it was possible that it was the other way around (bad geometry causing abnormal wear patterns and abnormal guide wear). Classic chicken and the egg scenario.


.

MTIRC6Z

Actually you can determine if the pedestal height is correct by taking appropriate measurements with the heads still on the car, assuming you know cam lift and can determine the exact height of the valve tip in relation to the center line of the rocker pivot. It's not very complicated and no "golden samples" are necessary...but don't forget to divide the cam lift by 2

Pad wear patterns are a symptom of pedestal height and thus are a very poor method of measurement, just as wipe patterns are with roller tipped rockers.

Cheers, Paul.

PS. IF you want to test how good your cylinder head expert is, ask him to verify IF your pedestal height is correct. IF he doesn't ask you what your cam lift is, find another expert.

American Heritage

Bump for some great cylinder head packages at a Great price

American Heritage

We have received and reworked 6 sets of LS7 heads since we started this special on the Corvette Forum. We are going to keep running this special through the end of the year. PM us if you would like any additional information.

'06 Quicksilver Z06

Awesome.

Glad to see people taking care of this matter.

I knew when you guys offered this that people were going to jump on it.

youzzi714

My Z has 12k miles on it since American Heritage did my heads, cam and some other goodies and it runs great!

kotik

what would you recommend for me?

I'm stationed in Germany. Lots of autobahn. Mostly cruise at 140+mph, a lot of WOT, and top speed runs. Track at least once a month. I also really want headers...

I'd like to stay at $1k price point. Would I need bolts and gaskets on top of this price? Do you happen to have a set of heads in rotation? How much is shipping to
PSC 2, BOX 7977
APO AE 09012?

American Heritage

PM sent.

We have several of our heavy track time customers running our package #2 and/or #4 with great results.

American Heritage

Thanks,

Most of the orders have been for our powder metal guides and the F2042P valves (package #4).

ctsv510

Are most retaining the stock springs with those valves?

Vette @ 71

What are you doing differently to prevent PM guide wear, assuming the heads you worked had PM guides which had/have shown some or much wear? TIA

American Heritage

No, 95% of our orders have been with new dual valve springs with titanium retainers and machined valve locks ($300)

American Heritage

We machine them correctly. We are not using the OEM powder metal guides. We use a proprietary aftermarket powder metal guide that we have had wonderful results with.

American Heritage

Bump this thread for the new year!!!