Racing E9 Question

[Malc]

I have always wondered...
Lots of pictures show racing E9's with massive flared wings (fenders) and huge tyres
Was the suspension bespoke?
I can't imagine the wheel bearings and the "lively" rear end being able to cope with all the strain.

In addition were the flares structural or just "bolted on"? Knowing how fragile the shell is I can't imagine that the original winds were cut off and fibreglass ones stuck on!

I really should be told!
Malc

This is all part of a cunning plan to get the missus even more annoyed, well what am I going to do with that spare shell dear????

 

[Philip Slate]

The later factory cars had special suspension and a lot of other special stuff specific to the race cars. Many privateer cars, like TBL, and even some of the Alpina cars had 'lightly' modified suspensions retaining the MacPherson struts up front and rear control arm assemblies in back. In TBL, which ran in IMSA in the '70s and SCCA (USA sports car racing) in the 80s, the front and rear wheel bearings appear to be stock although the front brake rotors are comprised of separate rotors and hats. And while many cars used five lug wheels, the factory cars, and probably the more affluent private entries, used center (centre) lock wheels. (Should mention that I replace the front wheel bearings at the beginning of every year and use only Red Line bearing grease) Not quite sure what you mean by a 'lively' rear end (although it does bring back some fond memories of my college days) but firm springs and a big anti-roll bar in addition to a fully locked differential make the car very predictable and very throttle steerable.

As for the big wings, they are indeed just glass fibre. The structural rigidity comes from the roll cage, which in the case of TBL is a 12 or 13 (I keep forgetting which) point cage, the front of which is attached to the forward frame rails. It is possible to choose any solid point on the frame and jack the car up from there with no body flex what-so-ever.

As TBL is undergoing an engine transplant at this very moment, I'd be happy to take some pics of anything you might like to see, on TBL that is.

As for your spare shell, it's crying out to be made into a race car.

 

[Malc]

Thanks Phillip
I would indeed like to see some pictures. I had thought that huge, ie wide tyres would need a massive offsett to fit and thus put loads of strain on the wheel bearings
As to the rear end (suspension :wink: ) The term"lively" came about because of all the "rubber" mounts for the beam, swing arms and the rear diff mount. I guess some racing folk might of changed them for nylon or similar.

I understand re the cage being the item for the strength. When fitting those huge wings (fenders) did you, or others, just cut the original ones off to save weight etc etc?
Thanks agaain
Malc

 

[soxrus]

race CSl's

Art Simonds is most likely the best source for chassis upgrade info to the race CSL's (especially Groupe 2 from '72 and '73) in the US today, as he was the chief fabricator on '997 (and the 1st. 4 factory CSL race cars) when it was built by BMW Motorsport . Please refer to the article in Bimmer about the CSL, Art built over a 7 year period for a customer on the left coast. This street CSL has many of Art's tricks for firming up these "less than stiff coupe chassis platforms"

While '997 does not have the suspension refinements/upgrades, that the later CSL's received after '73 in Europe, and later by BMW NA for IMSA racing (thank God for John Buffum!!!) I can tell you that the suspension is a "different animal" than a stock CSL. The wheel bearings are different/larger, because of the racing "single nut" spindle assemblies. The chassis was completly "seam welded" with extensive bracing to provide a stiffer racing platform !!! And of cource the roll cage helps tremendously !!!! Front and rear suspensions are completly adjustable with upper and lower fully adjustable control arms. Much of the rear tire width you mention is actually under the car as the rear strut/shock assembly mounting points were moved inboard to the rear "package/hat rack" area to make room for this extra width !!!!

Kenny and myself will be working on returning '997 to the Vintage racing circuit very soon ......... I promise to post some suspension pics very soon.

The Martini racing CSL that I have, was restored in Germany, as a street car and has only the "seam welding" and chassis strengthing left from its racing career. It never had the rear strut mounting points moved inboard to provide increased width tire clearance and better geometry and travel as the factory offering !!!

Any qualified race engineering shop can vastly improve on anything available from even 10 years ago ......... I've been toying with putting e46 m3 front and rear suspension under an e9 coupe chassis, and transplanting a dry-sumped S54 into a coupe to go BMWCCA club racing in ...... what a hoot that would be !!!!!

Be safe all, Jimmy