How much fabrication did you have to do to make it fit?

simply put, barely any. A few hammer strokes to the firewall and trans tunnel (around the valve bodies and pan), and custom motor mount arms (so that I could reuse my OEM m103 mounts and mount locations). I'll have pics this weekend that I'll post. Beyond that, I used the standard trans mount, and it bolted right up and put the motor in the correct position as well. No shortening of the driveshaft, and I just replaced the stock swaybar with one from a 500e.

So the drive shaft bolted right up to the tailshaft on the trannie without problems?



Did you use the stock fan and clutch? W201 Steeringbox?

Good questions! No, the tailshaft on the trans needs to be swapped out for the smaller 90 mm flange that is used in the 722.4 (m103) trans. It is as far as I can tell a straight swap, as the rear end of the 722.3x and 722.4 are the same aside from the flange outer diameter and also the speedo gear vice spacer bearing in the 722.3. I can't speak for the geometry of the w124, but I basically put the motor and trans in, and bolted the rear trans mount to the original location using the OE bracket. Miraculously this placed the motor in the exact location that it needed to be in (for clearance in the engine bay and trans tunnel), and after setting 5/8" clearance over the front crossmember (above the oil pan), the motor angle was also correct and the driveshaft slips right onto the pin on the trans output end. Does that make any sense? Its hard to explain things in words w/o pics....

There is not enough room to use the engine driven fan or clutch assembly. I'm going to be using an electric pusher fan on the other side of the radiator which will hopefully be sufficient (crossing fingers).

Oh yeah, not sure if I mentioned this, but you absolutely have to swap out the front swaybar for the 500e angled bar so that the 116/117 oil pan will clear. As it is, you will probably only have about an inch or so of clearance there, though it should sit slightly below the swaybar in terms of elevation.

I am putting the final touches on the motor mount arms, and assuming the m103 mounts in the same way in the 124 as it does in the 201, I would be happy to share the design with you. That would definitely save you some trouble
edit: I see in your sig that you have already done the 500e swaybar mod, so you are already one step ahead!

FWIW, there are a couple of C36 M104's on ebay right now. . .

I have 3.27, 3.06, and 2.87 diffs for my C36-powered W124 wagon, and the best daily-driver diff is the 2.87.

Good luck with the swap!

:-) neil
1988 E36T AMG ( http://www.silcom.com/~neilv/sportline )
1993 500E
1995 E320 wagon

Thanks man, its going to be interesting... I have thought long and hard about the M104, but I have the whole deal, computers and all for the V8.

I would personally much rather do the wiring on the CIS swap rather than messing around with the HFM conversion. Its almost plug and play with a MAS equipped m103, and even closer on a pre-MAS car.

Sounds like a great idea.

If there is room, go with the Euro true dual manifolds for a bit more air flow.

I'd certainly pull the heads and go through them while the motor is out. Polish the ports, three angle valve job, clean up the valve throats. I bet you could squeeze around 225-235hp from that motor no sweat.

Keep the stock US cams as they're shorter duration for better low speed TQ.

Guys, I have to ask, but why not drop an SBC 350 into it. Just because it's an MB engine, it's not going to make it any less of a Frankensteins car. At least with an SBC 350, parts are cheap and easy to come by.

I wouldn't use a Gen I or II small Chev. The amount of power that can be had from the Gen III+ motors is beyond insane. You can get 360rwhp from a puny 5.3 with a mild cam and all bolt ons.

Size....



I dont know if a GM motor will fit...


I know a 420 will!

I think resale wil be a lot better with an all benz rod.

The istallation will be simplified by the fact that many of the parts needed will be available from the factory since they offered the v8 in that chassis just not in the wagon. this will make maintenance easier too.

Tom W

Keeping the "pedigree" is just so much more elegant, especially if you want to have it serviced, and of course re-sale.

I have a M104 AMG powertrain in my W124 wagon, along with 500E calipers, master cylinder, brake booster, swaybars, and springs, so when I have on occassion dropped it off to the dealer or my local tech, they don't freak-out, and they usually have the parts on hand.

:-) neil

My indy mechanic said he will come in Sundays to work on my car when the shop is closed...


He doesnt want people to know that he services an oddball.

If you do a really good job, most of his customers would never know it's an oddball. Thats the only reason I want to hide my big air filters.

I have a 117 sitting on my garage floor. What measurements do you need.

John Roncallo