Author Topic: M180 to M130 Conversion/Swap  (Read 25 times)


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M180 to M130 Conversion/Swap
« on: August 08, 2019, 01:39:56 PM »
I've attached the same write up except with pictures below
I wanted to post a write of my experience swapping my 220S M180 to a 280S M130. There has been some info about this swap online but none that really detail the process. In my case it was a 1964 automatic to a 1969 automatic.

My old engine has compression readings ranging from 30psi to 100psi. The engine wasn't original to the car so I didnít feel bad about leaving the old motor behind. The new (old) engine was from a donor 280S that my friend Michael had lying around. This engine had dry compression readings between 160psi to 170psi on all cylinders: almost like new! You can see the condition of the donor below:

The first order of business was getting everything disconnected from both engines. That includes removing the hoods from both cars, the fuel linesÖ Iíve attached the procedure from the workshop manual below.

Once all was removed from both vehicles, it was time to actually remove the engines. I was able to rent an engine crane for 35$/day, not too bad.

The first to come out was the M180. Get that piece of junk outta here! Throughout the removal, my father and I had to change the length of the strap that was under the main pulley (changing the angle), so that the transmission could clear the firewall. It came out without too much of a fuss. The engine was placed in the rear of the donor car, making for a rear engine air-cooled motor, aka Volkswagen!

Next was the 280S engine. Again this one came out fairly easily by adjusting the angle of the engine. While we had it out, we took the time to power wash the engine and get all the years of crud off the new engine.
After that it was time to install the engine in to my finny. It took a little finagling to get engine in.

Most importantly is to watch out for the accelerator linkage coming off the firewall. If it doesnít slide through the ďslotĒ under the exhaust and above the engine mounts then it is impossible to do it later, and will most likely bend the linkage itself.
We placed a rolling jack under the transmission mount so that it wouldnít be sliding on the ground and could easily be moved around. Once the 2.8 liter was in, we were able to bolt the engine mounts on to the frame of the car, while still leaving the rear transmission mount on the jack.

Because the engine-transmission assembly is longer for the 2.8 liter, you need to cut a hole in the transmission tunnel. Iíve attached the photos of the hole in the tunnel. It was about 3 inches by 6 inches as you can see.

Also because of the longer assembly, the drive shaft needs to be shortened. It was difficult finding a machine shop or even a drive shaft shop that would shorten the drive shaft. They all said that they couldnít work on drive shafts that were friction welded together. I finally found a machine shop that could cut and weld the shaft back together. The trick is to scribe a line along the length of the shaft. This is so that when you cut out about 2.25 inches from the middle of the shaft, you can weld it back together, letting the weights be in the same relation to each other. That way you do not have to have the assembly re-balanced.
Once my driveshaft was modified, it fit back between the transmission and the 2nd half of the driveshaft. So I go the flex disk in there as well as a new transmission mount.

I put the cross member back in, using the metal mounts from the donor car (on the right).

The next area of concern is the speedometer cable. You have to use the speedometer cable from the donor car. The end that connects to the speedometer itself is different, so I just taped the speedometer end to the speedometer. Itís ugly, but it works well.

(The donor cable is on the left).

The final part was just reconnecting various items such as the fuel lines and electrical connections for the generator (I stayed with the generator because it didnít require any different wiring and was recently rebuilt).

We hooked up the battery and started it, and voilŗ! It started right up and sounded so much better! The power difference between a tired M180 and a young M130 is astounding. It feels like a new car!

Overall, this conversion took us about a week, working all day. Iíve never pulled an engine and neither had my father and we both found this quite easy. We were surprised at just how easy it was. Other than the driveshaft and the hole in the tunnel, it really is just a bolt in swap. I recommend this to anyone that has a tired old engine and can find a donor engine.

I hope this helps others that are considering it, and don't hesitate to ask questions if you have any!
« Last Edit: August 08, 2019, 04:16:04 PM by Bidart39 »