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-   -   GT3 top mounts with H&R coilovers (http://986forum.com/forums/performance-technical-chat/53511-gt3-top-mounts-h-r-coilovers.html)

method 08-03-2014 05:16 AM

GT3 top mounts with H&R coilovers
 
I've mounted a set of H&R monotube coilovers on my 986S, these coilovers can be used with the stock front top mount. The spring lands right into the stock, rubber-lined spring seat. It all works rather well.

Now, I'd like to get some extra camber as I track the car every now and then. I found a reasonably priced 996.343.181.9R GT3/Cup front top mounts that can be rotated for an extra degree of neg camber.
Diagram
http://986forum.com/forums/uploads01...1407071039.jpg

Now to my challenge: in the GT3, these are used with a spring perch/top hat that channels the force to the monoball whereas in other 986/996's the spring has a ruber lined spring seat in the top mount. Some after market top mounts allow for re-use of the original spring seat which is not how the GT3 part is designed.

I'm assuming that I need something like this:
MODE spring perch or perhaps the original GT3 part. I don't know what the inner diameter of the spring is - original and H&R should be the same since the same spring seat can be used.

Is there someone here who has done this or could help me in finding the right part(s)?

Brad Roberts 08-05-2014 08:12 AM

Forget using these with a stock spring (or a lowering spring from H&R)

Here is why:

The stock spring sits flush against the bottom of the OE shock mount (black plate with 3 studs)

Install these GT3 upper mounts? with the monoball adapter AND the billet upper spring perch in place? You've now RAISED the car a full 26mm's :barf:

GT3 mounts are designed for race cars. Not street cars with stock springs in place. They are designed to work with adjustable threaded body struts/shocks.

I cheat like a MotherF'er with the Tarett monoball upper mounts..









I mount them upside down so I DO NOT get the increase in ride height associated with running the Tarett mounts (his monoball is captured much better than how Porsche captured the monoball. The drawback is on the Tarett mounts? It increases the distance between the plate the upper mount :(

method 08-06-2014 12:04 AM

Thanks for your input, Brad! I'm not planning turning the Boxster into an SUV, however. :) My coilovers are adjustable (see first link in initial post) and I have plenty of thread to spare in order to compensate for the increased "overhead". And although my parts have a Porsche Motorsport part number they're identical to the ones on the stock, road going GT3's.

The problem is rather which hardware I need to add. It seems (hard to know for a fact since they're mounted on the car) that the inner diameter of the springs is roughly 70 mm. This would indicate that at least the Patrick Motorsport/MODE part would work since it's designed for the Bilstein PSS9 and its 70 mm ID springs. Does that sound reasonable?

Brad Roberts 08-06-2014 10:23 AM

Got it :) We don't use H&R for anything.. I did'nt *know* they had a threaded body coil over.

I'm well aware they came on the street cars :) Been dealing with the factory cups since the first imported cars for the USA from Kadach (99) :cheers:

I have several hats I can give you.. or I buy wholesale through Mode. They are in Arizona near Patrick (which is why he sells them)

In your pic of the monoball mounts? Your missing two pieces. One each for the plates. Do you have them? and they are not in the pictures? its the misaligment spacer for the monoball. If the person who removed them from the car doesn't know what they are doing? they will leave that spacer on the shock and not know it :(

method 08-07-2014 02:22 AM

The H&R kits (available in Road and Clubsport variants) are actually rather popular over here as a mid-range option.

Although the picture I attached above is not my pair, you're quite right regarding the missing piece. It's the nut/washer on top (997 343 561 90, item no 2 on the diagram linked above). As my top mounts are spotless I don't believe they have ever been installed on a car. I need to get a hold of a couple of those as well.

Just found a picture of a PSS9 installed with the stock top mount:
http://986forum.com/forums/uploads01...1407406552.jpg
I guess that means that at least the MODE part would fit my coilovers since they and the PSS9's seem to have the same inner diameter as stock.

Brad Roberts 08-07-2014 10:12 AM

The *nut* part number is: 996.343.561.91

USA retail is 18.42x2

Yes.. I run metric SWIFT springs on everything.. all of our BoxsterSpec race cars run on the PSS9 and I'm not a fan of having to machine/buy the alum bits needed to run a "standard" 2.25in or 2.5in spring.

Buy the mode pieces and be done with it.

method 08-09-2014 03:43 AM

Thanks, I appreciate you sharing your knowledge!

I tried to order the perch kit via ******************************************** but it was "no longer available". Other merchant quoted me outrageous ($200+) shipping fees - obviuosly nobody wants my business! :) Also, nobody on my side of the pond seem to sell this.

On top of that it seems that the GT3 perches I thought was an option really wasn't since they run 60 mm ID springs. Go figure.

Back to square one, then!

rfuerst911sc 08-09-2014 05:08 AM

Consider the no longer available from Auto Atlanta a blessing........thieving good for nothing business practices for many many years. I speak from personal experience. Spend your money else where.

Brad Roberts 08-09-2014 11:53 AM

I'd kinda listen to him :)

What do you need? or want me to get? I'm 15min. from the largest Porsche distribution center in the USA. I pick my parts up on Will Call when I'm in a rush.. and Porsche Motorsports North America is 45min. from me.

I will say this: my crew and I leave for a race in Colorado on Wed. of next week (Wed. night) so if you want me to take care of this (the parts are available) then I will need to hear back from you by Tues. no later.

method 09-07-2014 08:11 AM

Thanks for your support, all!

In the middle of this process I started thinking about my trackday pal who runs a mech workshop. I talked to him and supplied some simple drawings:
http://986forum.com/forums/uploads01...1410104431.jpg

These beauties arrived - just what the doctor ordered:
http://986forum.com/forums/uploads01...1410105326.jpg
http://986forum.com/forums/uploads01...1410105983.jpg

So, now all I need is the most expensive nut in the world; the one that sits atop the supporting mount. I heard the guy at my local dealership say the magic words "Porsche Motorsports department" and knew it would take plenty time and money toi get them...


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