1975 450SL engine options
 

I have a 450 SL that at some point had a M130 inline six installed. I would like to swap back to a V8. My preference would be a 75 4.5l that was originally in this car but they are hard to come by at a reasonable price.

My local salvage yard is pack full of 1990 - 2005 Mercedes, but I was told anything after 95 will not work due to the ECU/CAN. So I guess i'm looking for 85 or older 4.5, 5.0 or 4.2L V8's.

What are the bolt in options here, none of the 95 or newer engines will drop in?

Thanks
Mike

Don't know if a DOHC engine will fit-they won't fit some of the SOHC chassis cars. Maybe a 5.6L from a 560SEL or 560SL? But the problem with used engines from Pick N Pull type venues is unknown condition. Most were driven until they won't go any more or could not be repaired. Maybe buy a used car with the engine you want and take the carcass to the dismantler. Do you want to deal with adapting another FI system or stay with the D-jet that was originally in your car? You really need a complete car to get all the pieces. Did they cut the wiring harness?

Here's your engine:
https://www.peachparts.com/shopforum/mercedes-benz-used-parts-sale-wanted/396340-w116-parts-available.html

Location helps. I have a 73 280SEL 4.5 that I plan on dismantling soon. It will have the correct engine. It's in Texas.

1) Because there is a 6-cyl. and a matching transmission installed, any V8 installation will require the matching transmission for that engine.

2) Any M116 or M117 will bolt in. 1973-1991 3.5L, 3.8L, 4.2L, 4.5L, 5.0L, 5.6L, both iron block, and aluminum block engines.
Depending on what remains of the original plumbing and wiring, the details of a re-installation of a V8 may indeed be devilish.

I wouldn't use the 1975 engine. Those manifold mounted cats are horrible. Sticking with the same injection system would be a good idea unless you like doing everything the hard way.
Those old 4.5's were very strong engines and the bodies usually rusted out before the engine gave up. Manifold vacuum leaks are a big problem so you might want to consider going through it before installation.

I am on Long Island NY and have at least two 4.5 v8s collecting dust. You are welcome to them if you help pull them from the cars they are in (transmission too).

You definitely need to figure out what needs to be re-done. As already said, you don't want a factory '75 exhaust. They did some scary things in 74 and 75 for emissions that earlier and later cars don't have.

My cars, like yours already, won't supply suitable FI components because they've been sitting too long. Getting rebuild CIS parts elsewhere is straight forward, but pricey. This isn't the kind of work you want to pay somebody else to do. But if you're handy, it can be done. An exhaust system change-over should be all you need to wrap up the work. (presuming your current drive shaft is the right length for the swap back).

Having said all that, what's wrong with the M130 other than it's carb'd, the wrong engine and less HP than the V8?

If you're really handy and into more modern technology, doing a megasquirt conversion for the FI and ignition system might be a good option. Better yet, if you can do that, go for an M103 or M104 straight 6 and enjoy better performance and cheaper parts.

-CTH

I have a 4.5 engine and trans in my 74 project that needs to come out and can if I have the incentive too. Right now I'm working on putting my new engine on a different sub frame.

As far as things that will bolt in these cars had M110, M103, and M116/117. A M117 and M119 have similar blocks but I'm not sure if they're bolt in swaps for eachother. I am doing a M104 in my car using M103 parts because the m104 is basically a DOHC m103 but I need a different pan.

Honestly if you just want something that's stock its not hard to find these cars in stock condition.

If it does not need to be smogged that opens up more options also.