W108 280SE 4.5 powertrain inquiry

[suckapunks]

I had just heard that the automatic tranny during the 68-74-ish era was made by GM and is the same as the TH350 but has Mercedes name on it. At the same time I also heard the a/c was made by Frigidaire also related to GM. Is this the truth? If so, is it feasible to install the 700R tranny to get the overdrive and improve fuel economy? If we're going this far, is it also possible to swap out the rear axle gears easily to increase the gearing to make acceleration a little more exciting than the 12 second 0-60 ?

Any insights would be appreciated and any details on pitfalls in doing something like this would be also greatly appreciated.

Feel free to send email directly to me as well.

Regards,
Bob

[Larry Delor]

The pan sure doesn't look like the pan from a 350. I think it was a few years prior, that they used some GM parts.
A/C was either Behr, or Kühlmeister.

[JimFreeh]

Originally Posted by suckapunks

I had just heard that the automatic tranny during the 68-74-ish era was made by GM and is the same as the TH350 but has Mercedes name on it. At the same time I also heard the a/c was made by Frigidaire also related to GM. Is this the truth? If so, is it feasible to install the 700R tranny to get the overdrive and improve fuel economy? If we're going this far, is it also possible to swap out the rear axle gears easily to increase the gearing to make acceleration a little more exciting than the 12 second 0-60 ?

Any insights would be appreciated and any details on pitfalls in doing something like this would be also greatly appreciated.

Feel free to send email directly to me as well.

Regards,
Bob

Any axle out of a W108 six cylinder will give you a higher numerically ratio.
Fridgidaire compressors are found on lots of MB applications in the seventies. V-8s and diesels used them, albeit they were two different styles. The Sankyo (sp?) compressors replaced the GM units.

Jim

[Larry Delor]

I wasn't thinking about compressor brand.
From what I've seen, there is either a York (piston), or an R4(Radial) to be found until the mid 80's (and maybe even late 80's).

[JimFreeh]

Originally Posted by Larry Delor

I wasn't thinking about compressor brand.
From what I've seen, there is either a York (piston), or an R4(Radial) to be found until the mid 80's (and maybe even late 80's).

R-4 was on the diesels, A-6 was on the V-8s. No other GM/Fridgidaire stuff on the cars.

York is not a GM product, and was also very common on peroid Fords and AMCs.

Jim

[alabbasi]

I've seen a Frigidaire set up on a 6.3 that was for sale in Texas a couple of years ago. It had a small under dash unit (really small). But looked quite well fitted. Maybe a dealer installed option.

I believe that the car was bought by the guy who runs the German M-100 site (I was the second highest bidder).

[Tomguy]

FWIW, if your 4.5 takes 12 seconds to get to 60, something is wrong with it. Maybe you're only running on 6-7 cylinders?

If you want more acceleration while maintaining economy I do believe a 3.5's tranny (4 speed) even though it's fluid coupling vs torque converted will do it faster.