jstyer

Hey guys,

I'm looking to put together some custom valved Bilstein cups, and I'm on the hunt for some info.

Firstly, what spring heights are you guys running? I have seen 150mm springs on the rear and 120mm on the front. However, I haven't found many options in spring rate for these heights from Eibach/H&R. I'd be interested in hearing everyone's thoughts on running 110mm and 140mm, vs 130mm and 160mm. I'm leaning towards the longer springs, 110mm seems mighty short.

Also, I know nothing about tender springs... Any lengths, rates, info would be greatly appreciated.

I've noticed that the H&R versions of the shocks have outside locating rings on the rear shocks between the main and tender springs, and inside locating rings on the front shocks. Does the original Bilstein have the same design?

Lastly, where do you guys like to source top spring perches, lock rings, and roll bar mounts?

Cheers, Justin

jstyer

Bump back to front page... Anybody? Bueller? Bueller?

Bill Verburg

I run Eibach 900/225/600 front and 900/225/750 rear, perches/locks etc. were purchased from the shop that installed them

I don't run tenders to avoid the double set that they imply
front

rear

jstyer

Ya... I used the wrong term. I meant a zero rate helper spring, not tender spring. I like the idea of keeping the main spring snug up against the perch during full droop.

Have you ever had any noise/issues due to not running a helper?

Bill Verburg

No, it works fine and w/o any noise. There is so little travel that the only time they separate is on a lift

Hopefully Cupcar will chime in, he used the same shocks(revalved of course) and H&R springs w/ a tender

Cupcar

Been OOT and my Rennlist membership expired, sorry for late reply. Here are thoughts off top of my head.

The Supercup struts have 65 mm long top studs, RS is 72 mm and normal is 42 mm I think.

The reason Supercup are shorter than RS is that the bearing sealing boot is eliminated in Supercup by machining off the flange that the seal attaches too, thus creating clearance between the spring top hat and mount bottom for required angular movement.

So the easy way to make Supercup + RS mount work in the front is to machine off the boot flange from the mount, use 996 GT3 spring top hats (dealer part, same as Supercup) and fabricate a spacer to go between the monoball bottom and top hat.

Keeping the seal in front complicates things because, so the strut has clearance at the bottom to angulate, a tube nut has to be fabricated to allow the top stud to nest deeper into the monoball and a longer spacer under the monoball has to be fabricated. I used modified PSS9/10 spring top hats here because the GT3 top hat is too flat and restricted motion.

The bottom nuts are available from Bilstein and IIRC, the struts came with them and I had to source the rears. For the rear the 993 spring top hat works fine along with the RS monoball and seal plus RS spacers which are a dealer part.

Use 60 mm Eibach or H&R springs and you are good to go. I used Eibach spring couplers in a tandem spring arrangement. Eibach couplers are what I believe are what factory used since they look identical to me and Eibach is an OEM for Porsche stab bars.

Edit: one more thing is for the rear using RS mounts a racing style cut out top nut (RS with drilled top) has to be used to clear the shock rod.

Cupcar

Done, PM me if you need more info. Bob