Bilstein Sports for rear, early cars

[JohnJL]

The Suspension wizard shows a rear Bilstein Heavy Duty for the 1971 but the rear sport shocks start at 1972.


I've got a 1971 with thick torsion arms (dont know which right now) and need to swap them out. The green shocks in there now (boge?) have slop in them and the ride is crap.

Will Pelican's rear Sport Bilsteins fit my 1971T?

Pelican Parts.com - Bilstein Sport Shocks & Struts

[Wil Ferch]

I know they're not Bilsteins, but you might want to consider Koni-Yellow-Sport rears...model 8210-1159, might fit your car ( check). Nice....top adjustable for stiffness via a removable plastic handwheel, and shock body is shorter by 2" than normal that would still allow a functioning range if car ever gets lowered.

[Bob Kontak]

This is a very good question, John. Look at the Bilsteinshocks.com website and they show HD and Sport Bilsteins for 71 BUT the part numbers and prices are the same. Look at 1973 and there are different part numbers (Sports number closely matches the PP number) and they are more expensive.

I think that Bilstein has a fixed template for their website presentation and there may not be a Sport shock pre-1973. This means even though both HD and Sport are shown for sale the same part number indicates only one shock available.

I would get on the horn with Bilstein and talk to them.

[Scott Clarke]

The '72 shocks use a 14mm bolt, and your '71 uses a 12mm bolt. Also, the later shock is about an inch longer than the earlier one. This is because the rear cross member was revised in '72, angling the shocks forward.

You should determine the t-bar size before deciding on a shock. For 27mm and smaller, the HD is the recommended choice.

[Bob Kontak]

OK - So I have stock rear torsion bars on my 81 that are 24.1mm. I put Bilstein Sports all the way around. I have the HD ones in the attic.

Is their a downside to using the sport shocks with the smaller bars? I did not notice a big difference in ride quality.

[UrQuattro]

Bob, when you said that you noticed a big change in Ride quality, is it better, or worse?

I would imagine that it's probably a bit (or maybe more than a bit) worse? The complaint from journalists when they tested these Cara new and they had the optional bilstein shocks (which I'm guessing are hd's), that the shocks made the ride way too harsh, and actually preferred the stock boge setup. I don't know about their reaction to the koni option though.

Now thati think of it, is that why people consider HD's satisfactory for tbars that are significantly larger than stock - because the stock bilsteins were over-dampening the stock tbars, making them a better fit for the bigger bars that people are installing?

Btw, does anyone know the actual numerical difference in dampening rates between sports and hd's? Percentage difference is fine. I don't quite understand what the valving numbers mean when they are listed for compression and rebound.

Michael

[Bob Kontak]

Michael - You missed that I said NOT a big difference. Maybe a tiny touch stiffer but nothing that warranted the $500 outlay.

It is no way too harsh. It is not a plush ride but neither are the Boge shocks in a 911.

For discussion, the factory "Sport" shocks are the HD Bilsteins. The Bilstein Sport shocks are valved stiffer. Correct me if I am wrong. My factory build sheet states I had sport shocks originally but in talking to Bilstein they stated the Porsche sport shock is their HD shock. If I bought the same shock then that explains why there is no ride difference.