New on List-Need Info on Engine Swap

P

Patton

Well-Known Member
Site Donor $
Messages
761
Reaction score
652
Location
Atlanta GA
The title line says it all. I've owned the car for 20 years, 18 of which it has sat in the garage. I've got the money,workspace, talent and, most importantly the time, to do this project this winter.

Details Car: Rust free '74 3.0CS automatic
Details Engine: Euro "85 m6 engine and driveline

I seem to recall that this type of engine swap has been done. Any help in directing me to links or phone numbers would be greatly appreciated.

Thanks in advance, Robert Patton--Atlanta Ga area 800-755-1715
 
Well, what do you want to know? It is pretty straight foreward, as far as swaps go.

You will have to pound your firewall in a bit, though, to clear the coolant return feed on the back of the head, if I recall right. You will also need a custom cut driveshaft.

Everything else pretty much bolts up, or isn't too hard to figure out.
 
The brake booster will also have to be changed/removed due to the intake runners and air box intruding into that space. The M6 uses a throttle cable v.s. the solid throttle linkage for the original engine. Someone on this list has fab'd a nice linkage to cable set up (sorry, don't remember who) whereas I have adapted a solid linkage (no cable) setup. The radiator hoses are different which includes the overflow tank hose also. The M6 has Motronic injection/ignition and requires a special bell housing for the ignition and injection sensors. You will also need a place to put the Motronic ECU, preferably in the cab, not the engine compartment. Hopefully the wiring harness for the M6 is still in place on the engine which will make things a lot easier. As for auxillary items like power steering and A/C, can't help you there, but as the blocks are very similar, that should be fairly straight forward. That's all I can think of for now. Hope this is of some use.
 
Well, what do you know...x-atlasO you're just down the road from me...come on up to exit 13 off of GA400 and say hello. Or, give me a call at 770-886-2500 as I'd prefer not to reinvent the wheel.

I'm fortunate in that the donor car has the wiring harness A/C, P/S alternator, etc., still in place. I get to remove them from the car.I'm going to see if the old M6 engine will crank this weekend.

Other tips? Print or web links?

Thanks in advance, Robert Patton
 
Atlas, any time 9am-7pm. Seems like I'm always here at the shop.
770-886-2500.

Good news, after 3 years the old M6 fired up rather easily. It is great to know that it runs prior to moving it to the coupe as I can only imagine that there will be other bugs to troubleshoot upon reassembly.

And, I found the article about the California guy that did an M5 engine, front subframe, driveline and rear subframe into his coupe. Not many details, as the article was mostly a fluff piece in European Car (I think).

Oh well...

Regards, Robert Patton
 
Yep, a nice idea article, but very little on the actual implementation. Of course, I don't know of any mag that puts out the real required info for any swap.

On the plus side, since the E24 has usually shared most of the frame components with its companion 5-er model (early = E12, later = E28) most of the article's info should still apply.
 
Atlas, I'm hoping that you are correct about the swap. This weekend I'll wheel-in the M6 and drop the front suspension, engine, driveline and rear end. I'm really good at taking things apart.... Then it is test fit and clean up time.Wish me luck.

Regards, Robert Patton
 
Project update: The engine front suspension, rear suspension, pedal box and power steering were removed from the "85 M6 last weekend. Next-up, the steering comes out of the already stripped 3.0 CS.

The pedal box and power steering are going to make for an interesting swap, as I can see that nothing is bolt-on/carryover from E9 chassis to the '85 M6 chassis. Has any one blazed this trail before?

Thanks in advance, Robert Patton 770-886-2500
 
You must log in or register to reply here.
Back
Top