93 300d 2.5 Turbo OM602 6 speed swap
 

I purchased a 93 300d back in December with the intent to swap in a manual a year down the road after enough time for research, two month into owning, the car moved my timeline up, and I crammed all my research into a month, and after 6 months on stands I now have a 6 speed om602. I thought I'd share my experience since during my research I never found any info on what would defiantly work, only what "should" work. So now I can speak to what WILL WORK.

Here are my parts:

-93 300d 2.5 Turbo
-02 C230 Kompressor 6 speed
-02 C230 Kompressor shift linkage
-02 C230 Kompressor shift linkage mount (needs customized)
-311 CDI Sprinter flywheel, clutch, and pressure plate
-03 SLK clutch and brake pedal assembly
-03 SLK master cylinder
-Wilwood remote fill master cylinder reservoir kit
-Custom made 36" braided clutch line (need the master cylinder nut from the SLK and the trans connector from the C230)
-stock driveshaft lengthened 2 7/8" (if I was to do it again i would only lengthen it 2 5/8")
-94 E420 Electronic Speedo
-Dakota Digital SGI-5
-Intellitronix S9020 GPS speed sender (I do not recommend this, it is slow to react and looses signal easily, I will be replacing with a universal driveshaft speed sender)

2nd attached pic is the c230 trans 3rd attached is auto vs manual trans

Flywheel, clutch and pressure plate where bolt on, same amount of teeth so 100% compatible with stock starter and tach sensor.

Wow, that is very impressive. I can't imagine the research you did to figure all that out. Congratulations!

The pedal comparison pic show the difference in the top mount point, all I did was shave off the 5th mounting point on the slk pedals and they are stilll rock solid when installed.

flywheel, clutch and pressure plate, and trans installed.

third pic is the customized reverse light and neutral safety switch cable, just to note I used a 93 brake switch as my neutral safety switch as the c230 neutral safety switch is closed normally and open when depressed and the brake switch is open normally and closed when depressed.

customized the 300d trans mount to work with the 6 speed, and the c230 shift linkage mount to work with the 300d

pic of lengthened driveshaft and then some pics of some superficial fixes. S600 style grille, and indeglo gauges from moman, along with uv paint on the needles and uv led's in place of the standard dash lights.

What differential gears did you use? The stock 2.65 would be pretty tall unless the 6-speed has really low gears.

Also how does it drive? I wasn't super impressed with the 93 300D 5-speed that I drove. It did get great fuel economy on the freeway though.

:euro:

Currently I only have the stock differential in it, and yes it needs steeper gears (I knew this and it's in the plans, but wanted it on the road first.) that being said it is a vast improvement from the 4 speed auto. Here is the trans gearing:
1) 4.46:1 2)2.61 3)1.72 4)1.25 5)1.00 6).84 Rev)4.06

As far as how it drives, I was building it with the possibility of selling it once complete, but after driving it, it will stay in my collection for a long time coming. Don't get me wrong there is lots of room for improvement, but it is the most enjoyable ride I have owned, and now I have a lot more plans for it in the near future, hopefully... But first up is the rear diff(I have the list of diffs from the different models somewhere, I just have to find it, and then also find the right donor,) and a garret t25/t28 hybrid.

WOW thats an excellent project, thank you for sharing. Do you have a link on where to get those gauges?

That car should return better than 40mpg highway. Instead of swapping out the 2.65 diff I would try to improve the engine first. Open up the exhaust, ditch the EGR, ARV (if you have one), ALDA and any intake restrictions, rebuilt the injectors and maybe a manual boost controller. On my OM603 with the stock 2.64 diff, 3.86:1 first gear and 0.80:1 fifth, the power is more than adequate after those modifications. I know you're playing with 1 less cyl but its worth a shot. 2000rpm at 70mph is priceless and I can't argue with the fuel economy.

cheers

I agree to try to use the stock diff. Won't the car hold a speed on level ground? If it holds a good cruise speed on level ground I would keep it as is. With a 446 first gear you can stand a tall final drive imho.

Awesome work!

Please post when you locate the list as I'm looking for a donor also for a 2.5 that's received the traditional 5-speed swap.

Gauges faces (they go over stock faces) are from http://moman.eu/ I first found them on ebay, and then found the site, really good product.

as far as the egr/avr goes, it will be eliminated (along with the rest of the vacuum system on the turbo side) when I do the t25/t28 hybrid / rebuild, I have all the parts, I just need to find some time for the project. And a straight pipe is also in the works.

and as for the alda.... well, I don't want to open up a can of worms here, I know the removal is controversial, but I haven't decided what I'm doing yet, I turned it up with great results so far, but once I get a little more air flow I might end up removing it completely...

thanks for everyones positive, and constructive feedback, it is always appreciated (even if i end up doing something else...)

Unless you plan on a VNT/VGT I would keep the ALDA. I honestly don't understand the point of extra gears unless it was cheaper. If 4th was 1.0 and 5th 0.93 and 6th 0.84 that would be swell. Be careful of your EGT's in overdrive. I find that my engine runs much cooler in 4th compared to 5th at the same speed/incline. I can hit 60 in 2nd gear now, adding more gears would simply mean a slower time to speed.

All the same still cool swap. I believe the 6spd is higher rated torque than any of the 5 speeds including the dogleg 16v. Do you happen to know if that is true? I can probably dig up that ref somewhere. It is a real concern for me.

w124

220 E / E 220 (124.022): man 3.67, aut 3.07
230 E (124.023): 4man 3.27, 5man 3.27 (up to 8/1989) 3.46 (from 9/1989), aut 3.27
260 E (124.026): man 3.27 (up to 8/1989) 3.92 (from 9/1989), aut 3.27
260 E lang (124.027): man 3.92, aut 3.46
300 E (124.030): man 3.07 (up to 8/1989) 3.67 (from 9/1989), aut 3.07
300 CE (124.050): man 3.07 (up to 8/1989) 3.67 (from 9/1989), aut 3.07
300 TE (124.090): man 3.27 (up to 8/1989) 3.92 (from 9/1989), aut 3.27
200 CE / E 200 C (124.040): man 3.67, aut 3.27
220 CE / E 220 C (124.042): man 3.67, aut 3.07
250 D / E 250 (124.125/124.126): man 3.67, aut. 3.07
E 250 D turbo (124.128): man 3.46, aut. 2.65

The first gear is significantly lower in that 6 speed allowing more comfortable take off from stop. With my five speed od conversion on the 300D with 307 diff, taking off was tricky with the very tall first gear.