can some one point me to the formal spec for this and how/where to measure this to verify?

 

search voodoo kicked in slow...
https://rennlist.com/forums/gt4/8972...l#post13025179

combined with
https://rennlist.com/forums/gt4/9085...l#post13507883

 

This post has a write-up from the dealer technician verifying the specs in the second link you posted above are accurate:

https://rennlist.com/forums/gt4/9461...l#post13552275

EDIT: Ha! Upon reading the technicians write-up in the link above, I see he got the tolerance wrong. It's +2/-0 mm, not +/- 2mm. IOW, shouldn't be below 109mm front, 130 mm rear, but can be 2mm higher. I have a copy of the page right out of the WSM he gave me, and he just typed the tolerance wrong in his write-up.

 

Thank you !!

 

On the forums I see spec as 109/130 as well as 106/133, do you know which one it is? (edit: it's 109/130)

106/133 has a 27 mm difference between front and rear (not really rake because they are measured differently) and the club sport has a minimum height of 79/105 as per IMSA rules, which is a 26 mm difference. The 109/130 numbers have a 21 mm difference so I'd tend to trust the 106/133 number more, but I'm just guessing (edit: wrongly guessing, the stock difference is 21 mm)

 

For the GT4, the spec is 109mm front, 130mm rear, tolerance on both is +2mm, -0mm.

Conditions per WSM: Full tank of fuel, no other weight in car whatsoever other than normal fluid levels.

The GT car tech at the Porsche dealer that did the work on my car gave the car a jounce front/rear to make sure the suspension was settled before measuring.

Dimensions must be take at precisely the front/rear locations shown in the WSM graphic.

I can post a screen shot of the WSM if that helps.

 

That would be cool to see the WSM. I wonder where the 106/133 numbers came from?

 

I have no idea why someone would post 106/133. It's incorrect for GT4. I'll put a screen shot of the WSM info up in the next day or so.

 

Thanks again for the info and offering to upload the WSM. You're right and it seems you already tracked down the problem.

Previously I found this post (https://rennlist.com/forums/gt4/9221...l#post13093330) that had the incorrect 106/133 mm numbers without an explanation of where the numbers came from, an educated guess (also this post has the numbers, not mentioning the guess part https://rennlist.com/forums/gt4/8972...t-results.html)

Then I found that the 106/133 data came originally from carl4's post which guesses at the ride height by subtracting 10 mm from the Cayman X73 ride height (https://rennlist.com/forums/gt4/8931...de-height.html)

Then I found your post that already said what I found above (https://rennlist.com/forums/gt4/9673...l#post13822278)

So thumbs up okie for the real data, thumbs up carl4 for guessing at something in the absence of real data and noting that it's a guess in one of his posts (though not in the other :-P). Let's make sure that in reporting someone else's guess, we remember to note again that it's a guess. They will no alternative facts on rennlist!

 

Here are some photos of the GT4 ride height specs from the WSM that I found laying around on the interweb somewhere:

 

Cool. The +2mm/-0mm is interesting. It's also good to note that this is the worldwide spec (no higher ride height US cars).