Amber Gramps

The guys at Rebel S assured me that going with the 150# Eibach springs was the perfect equivalent to the 27/28 rear bar. That may be so, but my car is on such a diet that it ended up being too harsh and nowhere near a match for my 21mm bars up front. In reality I think the reason I was steered toward the 150# Eibach springs is because Eibach doesn't make a lighter spring. I found the 60# and helper D Faulkner springs online after the fact and after searching for a solution. Turns out that D Faulkner springs are supposed to be a tightly held secret I am not supposed to know about. Even Steve W uses them on race builds. Actually got to talk to the owner of Faulkner and he assured me I would love his springs and that racers around the globe swear by them....he was right. Using the 2.25 dia will work on any Bilstein application, front or rear coilovers. Someday I will swap in the 100# Faulkner springs for the current 150's.
http://www.dfaulknersprings.com/acatalog/Specials.html

Reiver

Pretty cool there Doug.

race911

We fiddled with all this in the '80s, and even into the '90s, based on similar that was going on with the 944 world. (944 Turbos were just starting to be developed, and they needed help in the rear.) Likely it was that combination of not being able to acquire a low, low rate spring, coupled with a pretty unsophisticated world of damper modification.

My one car at the time, a ~2400 lb. 3.5L running 225/245 tires was two seconds a lap slower on the then-new 1.9 mile Thunderhill layout with the last setup I used--a Bilstein racing shock wrapped inside a torsion bar/spring combo that was said to provide about a 600 lb/in rear rate.

One hilarious place I experimented was for the road course at PIR. No data in those days, but I had so much wedge with dissimilar springs (and ride height) left to right you had to turn the car to the right to go straight. But it definitely worked on the high-ish banking that is T3 and T4 there. (Sadly, that road course has been obliterated to make way for NASCAR--and in 2016 again, Indy Car--garages.)

Amber Gramps

The cool part for me is being able to adjust ride height and camber in a matter of minutes.

Mondrian

One of the specialist on this side of the pond has developed a set up with KW coilovers in front but TB's/dampers in rear. I haven't driven that setup but all the experienced guys who have rave on about it. Have not actually come across anyone that is happy with full coilover conversion for road use over here and a few who actually reverted back to TB/dampers.

Fitting SSI will be challenging if not impossible if you go the coilover route on rears too.

Doug you must do a whole thread on your suspension setup as it sounds pretty unique.

Amber Gramps

I've got the opposite of what you site. I've got normal 21mm Tbars up front with revalved Bilstein Sports inserts (off Ed's Ruby) in Bilstein struts. All bushings are stock or Elephant rubber with turbo tie rods and a strut brace. I do also have 930 brakes with floating rotors on Rebel S hats and a 23mm MC....Insane.

Out back I've got an old set of Bilstein Sports that were rebuilt by Bilstein San Diego with new valves, seals, 14mm rods, oil, bushings, serial numbers, and such and matched to the 27/28mm spring rate with the coilovers described above from Rebel S. Rear also has adjustable drop links and WEVO swaybar mounts. All bushings are stock rubber

I've collected the proper banjos, bolts, and lines to reconfigure my rear brake lines after creating a **** storm over doing it "wrong" the first time.

https://rennlist.com/forums/attachme...ors-brake8.jpg

https://rennlist.com/forums/attachme...arage-dang.jpg

Anyway, you get the point...

http://forums.pelicanparts.com/porsc...alipers-6.html

rfloz

IIRC when Porsche was developing the 935 they couldn't get enough stiffness with the maximum sized T-Bars that would fit and the rules required the they use T-Bars. So, they just added "helper" coil over springs.

Just one of many rules Porsche bent with that car, e.g., the rear window opening had to be retained. It was, they just built a new rear half roof with a more aero rear window. Same w. stock door panels, rear bumper, etc., etc.

Steve Weiner-Rennsport Systems

Actually, they started that practice with the '73 RSR, '74 RSR, and 934.