I have a few questions about the possibility of putting an M120 into a 380SL

1) Will a 380SL transmission phyisically bold to an M120 Engine.

2) If so are there any ways to strengthen the 380SL trans.

3) Is a 560SL trans built stronger than a 380SL trans.

4) Assuming I have to get a transmission out of a S or SL 600. Is it likely that this transmission 4 speed or 5 speed version, will bolt in place and mate up to my drive shaft.

5) For the electronic controls on the S or SL 600 transmission, are they a seperate wire harness and computer. Or are they integrated with the engine controls.

6) Does anyone know the rear end ratio of an SL600 or S600

7) Is there any easy way of matching the speedo gears for mismatched rearends.

8) Does anyone have any dimensions for an M120 Engine.

Thank You
John Roncallo

Sorry for not getting back to you sooner. Here are a few of the answers.

1) Wrong bolt pattern. You could have a custom bellhousing made, but it would shred the trannie.

2&3)I would use the new 4/5 speed from the donor car, as the electronics would be the limiting factor for you auto. Not to mention it would also be the stronger candidate for you.

4) Custom driveshafts are cheap to get built. You just need toi make sure it is balanced that way you will not have any excessive vibrations.

5) It is seperate, but I think that the computer may just trip out without the computer. (I am not 100% about this, but that is what I was told by the mechanic.)

6) It is discussed that the SL600 has a rearend somewhere in the neighborhood of 2.65:1 or somewhere around that. I was considering looking fir something around a 3:1 rearend so I can get 0-60 in under 5.5 seconds.

7) Yes there is a little box that will allow you to recalibrate the electric speedo so that is read correctly.

8) I have those measurements for you. Sorry I haven't posted this earlier, but we had to move everything out and back in fo some carpets and walls to get put it. I know that the paper with the info is in the garage. Ill look take a gnader and see if it still exists, or if it has disappeared.

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-Justin

91 560 SEC AMG - other dogs dd
01 Honda S2000 - dogs dd
07 MB ML320 CDI - dd
16 Lexus IS250 - wifes dd

it's automatic.

Let me just say "BAD IDEA" alltogether. The M120 engine is huge and every aspect of installation into a 107 chassis would be completely custom as nothing would bolt up to anything or fit within the existing spaces. Assuming the impossible, that chassis is so under engineered for the weight and power of an M120 that it would be a death trap with one installed. You could easily buy a fleet of 129 600SL's for the cost of retrofitting M120 into a 107 chassis and making it even remotely safe enough to drive.

but i would think it should fit. we are talking of the v12, right? that engine is just two sixes on a common crank more or less. the 107 came with a six in europe which i suspect is longer than the newer sixes, and it came with a v8 which i suspect is no wider than the v12. now granted the top side of the v12 will look very massive with the twin cams etc, but i think the interference points are lower at the inner fenders. so before dismissing it out of hand, unless the previous poster has actually measured it or tried to put one in and it didnt fit, i would put a 107 next to a v12 eqiupped car and carefully measure everything.

now the question of chassis integrity is another issue. although it is certainly not likely to be as strong as the newer car, that chassis came with some pretty potent v8s expecially in europe, so bigger diffs and brakes should bolt right on.

the question of electrical compatability is something i have no knowledge of.

so if you are really interested i would continue to explore for hard info.

tom w

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[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

Trust me, the M120 is a very wide engine top to bottom, the 380Sl has a very narrow engine bay. My co-worker had to hammer on the frame rails to swap a 5.0 into his 107, originally a 380. Hey, I'm not saying it can't be done, money will do anything. I'm saying that if you strap a 1 liter 145hp, 14k rpm engine onto a moped, it's not gonna be even remotely in the same class as a FZ1, now change moped to 380SL and FZ1 to 600SL and you get my meaning. By the time you re-engineer the moped to be competitive you've spent way more than an FZ1 costs.

saying that a 5 liter wont bolt into a 107?

they came from the factory with 500s and 560s, do you suppose they completely redesigned the frame to fit in the later motors? also the 350 and 450 are 116 and 117 engines too. so i bet the 450 is dimensionally identical to the 500 and 560.

i still say measure both and see what you find.

it might not be practical for many reasons, but i would be surprised if the engine being too big is one of them.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

This is my take on it with only seeing pictures of the engines so far.

1) I estimate the engine will be about 7" longer, which means it wont fit lengthwise without moving the radiator. You have about 1" to move the engine back. If you take the one 1" you should now have a shoe horn fit. Radiator may have to be removed and replaced with a thin single core unit along with two small electric fan cooled radiators on each side.

2) It looks like the intake manifold may hit the brake booster. The brake booster may have to be moved under the fender and actuated with a bellcrank and linkage.

3) Where the engine bay in the 107 gets narrow is down about exhaust manifold level. The M-120 has wider heads but it is also a 60° V instead of a 90°. Hopefully these two facts wash out.

4) Totally unknown to me is the placement of the oil pan sump in relation to the sub frame. These can be modified but I'd rather not. There are also 2 oil pans for the M-120 one for the SL and another for the S. This widens the choices. But I belive the SL one (Forward Sump) is more likely a better solution.

5) Engine height unknown

All the reast of the stuff is the standard swap engine problem.

John Roncallo

Thanks Justin, I will be looking.

John Roncallo

excititng project.

hope it works out for you. you will keep us posted right?

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

I actually find this encouraging. I assume you are talking about an M119 5.0. Without measuring I would assume the M119 is wider in the exhaust manifold area where I am most concerned. The M119 is a 90° V8 with 4 cams and larger boars. With all other things being equal in design the 119 should be wider in this area.

As far as weight of engine, I am not too concerned because earlier 107 used iron block engines which I dont see being much lighter. Also I have already put a 302 CID Ford engine into a Pinto and a 350 CID Chevy engine into a Ferrari 308. Handeling takes a beating but they both worked well. To me the M120 installation into a 107 is a reasonable fit because it really is as much power as I dare push through a stock rear end. I'v also considered an AMG 55 engine, but with 100 extra HP over the M120, I have to be concerned with the rear end.

By the way do you have pictures of the M119 in the 107. This is another option I,v been considering.

John Roncallo

surprised if the 120 engine is lighter than the iron 4.5

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.

The 5.0 that took hammering on the frame to fit was a 117 not a 119

I stand corrected. I conferred with the tech who put a 5.0 117 into his 380SL, no hammering, just had to cut 4 inches out of the frame to fit the 5.0. So yes the chassis has to be modified to fit even the larger V8. The V12 dwarfs those V8's in comparison.

As fas as upgrades for brakes suspension ect. Every vehicle that M/B sells with a V12 option has brakes that are much bigger on the V12's than even on the V8 cars. So yes there are upgrades for the 107's brakes and yet they will still come in as inadequate for the massive amount of power and weight of the 12.

I'm sorry but my BS meter is pegged hard over. When the 380SL was being sold over here in the USA with a 116 3.8L V8, it was also being sold in Europe with the 117 5.0L V8. I doubt they had two different chassies.

John Roncallo

the only plausible thing that might require that is if he didnt have proper sl exhaust headers and tried to use sedan's.

could you submit pics of the car with the cut frame? i would be very interested to see which 4" he is doing without.

tom w

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.