300SD 4 Speed Conversion Has Begun (Phase 1 complete!)
 

Started today, we dropped the tranny, drive shaft, and pulled the auto shifter, dropped the 4 speed shifter in did a few other things. This is gonna be fun.

Question for you guys that have done this: What did you do about a speedometer? The SD is electronic and the sensor is off the tranny, the 4 speed won't do that. I am thinking of installing a mechanical speedo unit into the cluster, any thoughts or suggestions? Thanks.

I plan on doing the same swap to my SD, where did you get your driveshaft lengthened and what was the cost? No shops around here will do it

I'm planning on doing the shaft myself. I have done 2 already for other conversions. This is the 4th conversion I worked on, one was straight forward both 123 chasis, the other ones I cut and welded what was needed.

Not sure what mechanical speedo you can fit in there, but maybe one from a w124 may work.

However, there is a fella who had his Indy weld on some magnets or metal blocks (not sure which one) to the driveshaft and fitted the speed sensor from the tranny to pick up the speed from it. He stated it works like a charm.



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I think the W124 mechanical speedo would fit.

Sounds like a neat conversion! My dad would love to have a manual in his SD. :D (Not sure if I would in my SD, but in the 300E it would be fun!)

Do search on member "ICEFIRE", he did a swap I believe.

I had South Bay Driveline in San Jose, Ca do mine when I swapped the 300D. $150.00.

Charlie

Thanks for the replies. I would like to know more about the magnet set up to keep the speedo working right. If someone can find that I would appreiciate it. Meantime I will keep searching for the post.

What do you say we get this thing done over the weekend? I ready to chirp some tires!!! :wheelchair:

Took it out for a test drive Saturday. Very nice. This is gonna be fun. We are starting to get good at this.

Sounds cool. If they won't build it, build it yourself.

OK, we need pictures now, don`t be bashful :rolleyes:

We also need itemized details of what you had to tweek, bend and fabricate to make it all come together.

The peddles should just bolt in, but were there any clearance issues?

Iam sure the shifter assembly would have the same bolt pattern to attach to the floor.

What about the shift rods, seems they would have to be maybe a little longer?




And they said it couldn`t be done, good you didn`t listen to the Naysayers and went for it.

Must be a fun car to drive.

Dang. Now I have another project to put on the to do list. :eek:


I saw a SEC a guy installed a 603 (SDL) listed on CL. so that can be done too.
If you can dream it, you can do it.


Charlie

First off: Klaus Kallas is the MAN!! He knows his stuff around these cars.

Second: We didn't take pictures. ( I know, maybe next time.)

Third:

I don't remember how much we had to add to the drive shaft but the total length for the front half was 35.25 inches. (interesting that this is the same length as the one we did for the w201 190d conversion.) We were able to use a stock shift rod for the Reverse, a straight rod from an automatic for 1&2, and then added 4 inches to a stock rod for 3&4. The transmission sits up further in the tunnel so we had to add "ears" and redrill frame mount holes for the transmission mount cross member. Had to drill a hole in the floor board behind fuel pedal to route the clutch tubing. Klaus did some rewiring for the nuetral safety switch.

We still have to get the speedometer working.

The car is pretty damn fun to drive.

Next is Phase 2: swapping out differentials (3.07 to a 2.88)

Wow, good to know this is doable. How much more complicated is it than converting a w123 300D to a stick?

w123 to a w123 is straight forward.

video?