3.0 CSL DER TRAUMWAGEN

Lucas

Lucas

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While looking for interesting technical solutions regarding the suspension and braking systems, I came across the link below—an ad for a car with an interesting build.
The photos of the E9 chassis in the listing clearly show the extent of the modifications.


1975 BMW E9 CSL Racecar – 2shores

2shores.com 2shores.com


 
I didn’t realize how well done this car is. I knew it was an s38 tribute but I didn’t pay close attention to the motor work or suspension fab. Well done!

I have to wonder how much was spent on the fab work using whT In guessing was the #25 reference car. Vink Motorsport is far from inexpensive but they make/sell all of grp 5 suspension parts, clocked bell housing, motor mounts, etc.

www.vinkmotorsport.com

Product categories BMW E9

www.vinkmotorsport.com www.vinkmotorsport.com
 
On another CSL thread, a forum member suggested the pump near the differential is for cooling the diff fluid. (This thread has links to a lot of unique CSL parts.)
R

Post in thread 'CSL with a vertically mounted engine?'

Here's another @Markos post from 2020 that's relevant - custom bell housing or clocking ring?

Very nice shot of the dry sump oil pan:

Oil pump mounted on rear differential and powered off the driveshaft:
 
Here's a shot of the steering rack from the video. I don't see hydraulic hose connections.. this is why I believe it's just rack & pinion. I would love to know what the ratio is.

In addition, here's a photo from the vehicle's page at 2shores:

1975 BMW E9 CSL Racecar – 2shores

2shores.com 2shores.com
 

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Also, they cut and re-welded the bell housing to mount the motor vertically.. and I note two 8AN-style fluid connectors. Now I wonder if they're cooling the transmission fluid?
 

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As far as I know, Group 2 and Group 5 CSL's have been equiped with rack and pinion setups with ratios from 14.8:1 to 15.2:1.
No idea if this car has one of the rare original parts installed or some reproduction.
 
I was really intrigued by the steering on this build..

According to some quick research, ZF apparently built a "motorsport quick-turn" variant of their production rack & pinion from the E21; the quick turn is nominally three turns lock-to-lock. Photos of the quick-turn unit look remarkably similar to underbody photos on the 2shores car page; see attached photos.

The E21 entered production in 1975, so the availability of parts seems possible; I would love to hear more commentary on this from knowledgeable individuals...

Regarding the steering ratio:
  • Let's assume lock to lock is -30deg to +30deg on the wheels. 60 deg total
  • 3 turns lock-to-lock is 3 * 360 deg = 1080deg.
  • Turn ratio: 1080 deg/60 deg = 18:1

However, there are companies that make quicker rack & pinion upgrades:
www.pafclassic.com

Short Steering Rack Kit 2.5 turns BMW E21 LHD

Améliorez votre BMW E21 LHD avec le kit direction courte 2,5 tours. Précision, fiabilité compétition, fabriqué en Angleterre. Idéal rallye, endurance et circuit
www.pafclassic.com

If I repeat the calculations with this upgrade:
  • Same assumption - lock to lock is -30deg to +30deg on the wheels. 60 deg total
  • 2.5 turns lock-to-lock is 2.5 * 360 deg = 900deg.
  • Turn ratio: 900deg/60 deg = 15:1

15:1 is within the range mentioned above by @Clubsport_CSi
 

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I think transitioning a regular E9 or E3 to such a rack and pinion setup will require massive reconstruction of the full front suspension... But happy to learn if I am wrong here
:)
 
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