powdrhound

Pete, I think the reason you are seeing this discrepancy of 15mm is that you are comparing the plates with one in the high camber and the other in low camber configuration. When doing so, the difference is 14mm.

T10Chris

Great info in this thread. Thanks everyone for contributing.

Tom@TPC Racing

The photo is of a 996Cup bare tub sitting outside for 12 years. It was one of four Cup cars that we raced in GrandAm Rolex back in 2005. This was the test car for different setups. The opening was made so big to allow for 5-minute front spring change on pit lane during practice session. At that time JRZ didn't even offer the red **** so up with the airjack, off the front wheels, pop the top nut with an impact, let the shock drop and swap the spring of same height with no change to front camber and toe. On to green track the car goes for the driver to give feedback. We did have a good reason. This reason I am sure sounds ridiculous for most car owners however it did serve that very specific purpose for the team. You're right, for 99.9% of car owners, don't do it.

pete95zhn

I'm pretty sure had I compared both in low camber position, because that's what I use, but can't right now confirm that...as big A says: I'll be back...

powdrhound

Makes sense Tom. Thanks!

lordpantsington

Been looking for these measurements for a while, Thanks a bunch.

powdrhound

Okay. Here is the deal boys and girls. I got my grubby hands on both the OEM 996 and 997 versions of the Cup/GT2/GT3 upper mounts today. While the 996 mount has the asymmetrical shape and the 997 mount has the symmetrical hexagon shape, they are both 100% interchangeable. The stud/bolt pattern is identical at 118/110/110 and the monoball is also centered identically within the triangular bolt pattern for both mounts when comparing them in the low and high camber configurations. As such, as I mentioned in my post #15 above, the monoball boss for both the 996 and 997 mounts will just barely come in contact with the strut tower when in the high camber config and slid all the way inboard in the slots. You can see that the 997 OEM mount is also a dead ringer for the 996 JRZ mount as pictured below.

With that said, I have no idea why Porsche made the oddball shape for the 996 mount but I suspect that maybe the original 996.1 tub may have had different strut towers which required the cut outs in the mounts and that carried on until Porsche introduced the 997 versions. Just a guess though. There is certainly no clearance issue whatsoever of the 997 mounts when used in 996.2 and later cars. Hope all this puts the misinformation to rest once and for good.

Cheers...

oldskews4

I told you so over at 6GT3 forum when you first posted. I guess I'm not trust worthy

powdrhound

Sorry. I didn't notice your post till a few days later and without any proof besides a simple sentence saying they work, it's hard to believe that 100%. Again, way too many people saying the will fit and they won't fit for one reason or another. Again, what threw me off is Tom's previous posts regarding this in other threads. When guys that run race shops are posting stuff claiming up and down they won't fit, it's hard to discount them because you would typically assume they know what they're talking about. Unfortunately that was not the case here as pretty much every thing posted in this thread has been proven wrong. Not saying this to be deragatory, but one thing I've learned over the years is that in most cases for the most part the only person you can trust is yourself and have to verify everything yourself to be 100% sure.

norwegen911

What is the best solution for changing top mounts on 997 gt3? Original porsche or other brands?