MG Midget + Geo Metro 3cyl = MGeo

[gmichael52]

I have a 79 Midget, and have contemplated this Geo swap, primarily because of reliability issues (British cars are cool looking, but they are such gawd awful POS's)- and retain the OEM rear end and my Dayton wire wheels. JDM has turnkey Metro 1.0 liter 3 cylinders for 600 bucks- about the same price to find a 35-40 year old MG farm tractor motor block with crank that's been reconditioned and line bored by someone competent in dealing with British anchors. Samurai transmissions can be found on ebay although one can expect that the condition of the thing will be much similar to buying a British car transmission off of ebay.

I see a few potentially large hurdles to clear with this swap. Since you have it all apart and laying all over your garage floor Nimblemotors, aside from the obvious (Driveshaft, motor mounts, etc):

1. With the Metro engine now facing in the correct direction, the exhaust manifold is now on the left side of the engine. Is there enough clearance around the steering linkage shaft?

2. Metro's/Swift's & Samurais all have cable clutches. Midgets are set up for hydraulic.

3. The radiator. Can hoses be made up to get to the MG radiator? The only other low profile radiator I know of that will fit is an Audi 5000 radiator. There is not much room here. Custom builds ARE NOT CHEAP.

4. I forgot what #4 is.

5. I'm thinking the tunnel should be okay, as I did a rough measure of a Samurai 5 speed last summer when I was changing a clutch for a customer. However I didn't look at the the shifter location. These are tiny cars that fit like a shoe- a size 7.5 when you have a 9 inch foot. A few inches back may not seem like much, but you will be cursing shifting if the shifter is moved back any further than what it is- which also steals from the joy of shifting a manual shift transmission.

Any thoughts or observations?

[Frank Lee]

Clutches aren't too tough to reconfigure especially vs the big picture of swaps of this nature.

When I mated Toyota to Triumph I used the Triumph rad. even though the outlets were completely different vs. Toy. I just pieced together misc hoses with lil pieces of galvanized water pipe as splices. That proved to be the least trouble-prone aspect of the whole thing.

I had to fab up my own tunnel due to complete incompatibility. I made a cardboard pattern, then made it outta sheet metal, then carpeted it. The shifter was well ahead of stock tho. The answer was to bend the far longer Toy lever back.

The exhaust could be the toughest thing but who knows, it may not even be an issue.

[gmichael52]

That was my concern Frank- the exhaust for one, and to retain a hydraulic clutch. The latter can be improvised, but I may be wrong, but the last Metro 1 liter I looked at had the exhaust manifold on the left with the outlet facing the front. Can probably pick up a cheapy Pacesetter header for a flange and cut the pipes off, but I'd really like to know if this is (1) doable and (2) not too expensive- prior to seeing this post, I was figuring upwards of $4K- 800 for a motor to my door, 200-600 for a Samurai transmission, depending on how much I need to spend to remedy the sellers "selective ignorance", new clutch, a driveshaft- shorten one or have to get one made (500), a custom radiator (500), a header (if needed) and the pipe tubing to build one, to include repiping my exhaust, materials (steel that I can't steal, throttle cable, hoses, etc)and everything that I didn't plan (approximately $1000 or half of everything that I did plan for, whichever is higher)

all those little trips to the machine shop, etc. really add up when you start messing with stuff that engineers get paid to design- that is why they are engineers - that's the big kill on this idea. Nimblemotors is already in it deep, so I hope he chimes in.

However, I've seen Rover (Buick) V8's and GM V6's stuffed into them. Rotary's are an easy drop with the right mix and match of Mazda transmissions/tailshafts, and in all cases fuel economy isn't all that hot, besides overpowering a chassis that wouldn't dream of ever seeing 100 horsepower, no mater what bridge in England it was built under.

As for aero- keep it Brit. No reason to spend a lot of effort to make it look like a Miata, when in fact- a Miata is a better deal overall. I stripped off the rubber bumpers (that was at least 120 pounds), and run a 'glass hood. It's a 1600 pound vehicle .

[Frank Lee]

Oh yeah, the driveshaft... I was lucky, I cut both driveshafts and one just slid into the other! Weld em then go. Then I learned the hard way that the knuckles have to be lined up in order to not vibrate. V2 was fine.

[Wonderboy]

Like Frankly says, I don't think a custom radiator is necessary. In my swap I ended up routing twice the length of radiator hoses and just cobbling it all together. Just makes a block heater and full grill block more important with the increased volume of coolant. Exhaust is just about bendin' pipes and welding, don't forsee much problem there. The clutch might be a little beastly, but the shift linkage... that's gonna be the problem I'd love to see what you've got up your sleeve to solve. You may be able to get lucky with a driveshaft... there may be a few different lengths that fit into the G10 transmission splines maybe from different year samurais when there were changes to the wheelbase???(not sure if this happened) maybe from a sidekick? X90? Any other suzuki liable to have RWD? Very tricky stuff. I tried using a pipe sheath initially for one of my axles and it sheared apart during the maiden voyage. If you can't get a stock driveshaft to pop in without modification, that's the part I'd spend the most effort/money in getting right. I'd get two of them made and carry one right in the car with you at all times - this is the part most likely to get you stranded somewhere.

[nimblemotors]

I did a trial fit of the engine+trans, and the trans will fit into the stock tunnel.
Another fellow did a Suzuki 1.3L swap into his bugeye,
The Suzuki Swift GTi
so you can review that effort. A beautiful job and car.
The suzuki trans will fit the tunnel, the shifter is a little farther forward. The Samuri shifter is made for a truck, so you can't really use it as-is, so you can locate the knob where you want it when you modify the rod.

A Samuri trans is not easy to find these days. I first got a Tracker trans, and its a little different, the 1.6L "big block" has different lower mount holes, and the trans is a little beefier.
I have not done the clutch slave cylinder yet, but it will need some custom fabrication mounts. Shouldn't be any problem though.

The exhaust is not a problem regarding the steering. However, you will definitely need some work, as the stock pipe exits differently,
but the manifold should be OK.

I will be fabricating custom stainless steel headers,
and running the exhaust pipe through the trans tunnel for a lower ride height and better undercarriage aero.

Sure you can use the stock radiator. Just need a lot of piping since the G10 hoses exit out the "back", and the radiator is in the "front".
The stock radiator is copper and not particularly light, an aluminum unit would safe some weight.
I'm planning a unique radiator that I think will be an automotive first, maybe even patentable.

The driveshaft is always an issue in a swap, but a driveshaft shop can make whatever is needed not too expensive. The stock driveshaft is small and lightweight, the samurai yoke is similiar in size. I plan to make one in aluminum.
I've been doing lots of work on the my car, but mostly have been fabricating the fiberglass body panels:

http://nimblemotorsports.com/mgeo/trunkform.jpg

http://nimblemotorsports.com/mgeo/trunkrough.jpg

Doing the doors and hood now.

Jack Murray
Nimble Motorsports

Originally Posted by gmichael52

I have a 79 Midget, and have contemplated this Geo swap, primarily because of reliability issues (British cars are cool looking, but they are such gawd awful POS's)- and retain the OEM rear end and my Dayton wire wheels. JDM has turnkey Metro 1.0 liter 3 cylinders for 600 bucks- about the same price to find a 35-40 year old MG farm tractor motor block with crank that's been reconditioned and line bored by someone competent in dealing with British anchors. Samurai transmissions can be found on ebay although one can expect that the condition of the thing will be much similar to buying a British car transmission off of ebay.

I see a few potentially large hurdles to clear with this swap. Since you have it all apart and laying all over your garage floor Nimblemotors, aside from the obvious (Driveshaft, motor mounts, etc):

1. With the Metro engine now facing in the correct direction, the exhaust manifold is now on the left side of the engine. Is there enough clearance around the steering linkage shaft?

2. Metro's/Swift's & Samurais all have cable clutches. Midgets are set up for hydraulic.

3. The radiator. Can hoses be made up to get to the MG radiator? The only other low profile radiator I know of that will fit is an Audi 5000 radiator. There is not much room here. Custom builds ARE NOT CHEAP.

4. I forgot what #4 is.

5. I'm thinking the tunnel should be okay, as I did a rough measure of a Samurai 5 speed last summer when I was changing a clutch for a customer. However I didn't look at the the shifter location. These are tiny cars that fit like a shoe- a size 7.5 when you have a 9 inch foot. A few inches back may not seem like much, but you will be cursing shifting if the shifter is moved back any further than what it is- which also steals from the joy of shifting a manual shift transmission.

Any thoughts or observations?

[some_other_dave]

Hydro-to-cable kits are available for a bunch of different cars. The main work seems to be making sure the mounting for the slave cylinder and the linkage between it and the clutch arm are beefy enough.

Or you can get an hyraulic throwout bearing... They're neat and should work well, but you'll have to drop the trans to muck with it. One example:


-soD

[bestclimb]

Samurai stayed the same in the US. There was a minor redesign in 88 that gave them a shorter 5th gear, softer springs, and a bit different dash. Elsewhere they did have a long wheel base version, but there are not many here in the US.

it may be easier to mount a cable clutch pedal than fuss putting piston on the samurai transmission.

[Varn]

My dad bought me my first car a 4 year old AH Sprite Mk3.(1965) I was 18 and never could get it started in the winter but was a fun car. Yeah old tele man roll up windows!!

[Arragonis]

Wind up windows were not a total gain - you could no longer put your elbows into the doors compared with sliding ones. Plus the doors got heavier and more complicated with the mechanism.