R107 hotrod, weight loss

[BMWTom]

Hello everyone,

I'm new to this forum, and might be shunned immediately for my blasphemous ideas. I've found a '79 Euro 450sl that looks a little rough on the outside, but mechanically it's in pretty good condition and would make a decent driver. I can get the car for a song. I like these cars, but have always wanted to modify one so that it would have decent performance-nothing fancy, just more like a true sports car.

For starters, I'm thinking about stripping it of every weight consuming item possible, including the soft top and mechanism, replacing the US bumpers, removing AC and emissions equipment (I can more or less get away with this in my state), interior items, spare tire, replacing the seats with lighter ones etc. I would even consider cutting out sheet metal and taking off anything that adds significant weight.

I don't want a boulevard cruiser. Just a spartan SL, maybe even set up for autocross or other track events. Any thoughts on reducing weight?

Thanks,

Tom

[ericdee]

Buy a miata.

[BMWTom]

Purists need not reply.

[nobby]

You are on the right track.

That engine, though is the biggest anchor on that car. That being said, there is not much else you can do from what you've already included.

You might want to look for an aluminum hood.

[Stretch]

Originally Posted by BMWTom

Hello everyone,

I'm new to this forum, and might be shunned immediately for my blasphemous ideas. ...

Originally Posted by BMWTom

Purists need not reply.

Well assuming that people are purists and getting all in a bunch about them won't help you with your question.



I don't own an SL but going on the weight of both of my vehicles - particularly my W123 which has been stripped to a bare shell I can say that a Mercedes of that era is very well made.

There is loads of heavy sound proofing and rubber undercoat that can be removed as well as the obvious heavy bits in the interior. Structure-wise I imagine that it would be hard to remove any metal that wouldn't compromise safety - you'd have to start again with thinner metal I guess. But may be a circular punch to make some aircraft structure style holes in it? As indicated above an SL isn't really meant to be a light sports car.

If the rear suspension has the anti-dive aluminium trailing arm system then the standard steel trailing arms from a W123 / 1st gen W126 / W114/W115 will fit and I'm sure someone here would want the aluminium ones off of you.

[BMWTom]

Yes, I've read that the aluminum hood drops 60lbs. Are all of the
380sl and 560sl hoods aluminum?

[BMWTom]

Just for reference, I had a '67 250SL a couple of years ago, but had to sell it to recoup some losses. I took it on drives with my local PCA club a couple of times and took it to events the Northwest Classic Rally. I loved the car, but was always disappointed in the performance. Yes, it was fun to try and keep up with 997's on back roads and mountain passes, but it was a handful.

I understand the engineering and purpose of MB cars, but find it compelling to build a car more in the spirit of the early fifties racing cars.

[nobby]

Originally Posted by BMWTom

Yes, I've read that the aluminum hood drops 60lbs. Are all of the
380sl and 560sl hoods aluminum?

Don't quote me on this, but I believe the aluminum hoods started late 1980.

So I guess the answer would be yes.

But don't forget the 280, 300, 420 and 500SLs of that era. They too would have aluminum hoods