MG Midget + Geo Metro 3cyl = MGeo
 

Hello, let me introduce my MPG project, a '71 MG Midget, getting a Geo Metro 3-cyl engine (Suzuki G10).

The MG folks like a restoration, the Suzuki engine guys want more power,
so I've come here to show my project.

I'm trying to achieve a pretty high MPG with this little car.
I stripped out a Metro quite a while back for its trans and suspension for another EV project, and have had this engine collecting dust for a while.
Thought I might just use it for a backup generator, or maybe an air compressor, but I acquired a '71 MG Midget unfinished project at a great price and have decided to put the G10 motor in it, and build it for super high MPG. The Midget is a very small and light car, stock it is only 1500lbs.
The G10 engine is about 100lbs lighter than the iron 4-cyl that was stock.
And its has some pretty heavy sheet metal, so I think I can get its weight down to maybe 1200lbs.

I just got the engine running on a stand, going through all the wiring to strip out just what is needed to run the engine.

I'm trying to figure out how much time I should spend modifying the engine before I put it in the car. Been thinking I should just throw it in and get it running, but I really want to modify the G10 motor to make it lighter and get better MPG.

I want to replace the TBI fuel injection with my own system, convert it to port injection and distributerless ignition (coil on plug). Raise the compression significantly, and use water injection. Then tune it to maximize efficiency at around 2,000 rpm for 65mph cruising.

Make it hybrid -- removing the starter and alternator, and add a more powerful electric motor that will spin it as an assist, with a small
battery pack that can recharged from a socket (Plugin Hybrid).

Any comments or suggestions?

Jack Murray
Nimble Motorsports

http://nimblemotorsports.com/mgeo10.jpg

This sounds the the worlds most awesome project, I've always wanted to convert a Midget!! :thumbup:

Honestly I would just chuck the engine in. I don't know how much effort it's worth putting in to modify that engine. I think the time/money would be better spent buying a 1l diesel smart engine or a 660cc japanese kei engine if you want to go nuts with it.

Sounds cool, I was just on craigslist looking for a spitfire chassis. Awful nice of these folks to build lightweight cars for us to mess with isn't it?

My first car that I bought was a 70 Midget. It was a lot of fun but I spent a lot of time and money on it. The first new car that I bought was a Chevy Sprint. Back then, I bought it after riding a motorcycle with no car for two years. I looked at the 3 cyl Suzuki motor and saw a nice big 1000cc motorcycle motor and thought it was awesome. I drove the Sprint as if it were a sports car, and it was a great motor and great handling car. I would buy another today, if it were available.

So I think your matchup is a very good one.

Which transmission will you be using?

I've always liked the little sports cars, the TR6 was my favorite, eventually owned one, which I drove across the country. The TR6 is pretty rare today and not cheap when restored. They had a powerful straight 6. The MG midget isn't quite so valuable.

The real joy of the cars is rowing through the gears with the top down, hearing the growl of the engine!
So of course it has a 5-speed. The Suzuki Samurai is a RWD with the 1.3L engine,
and the trans bolts right up with the 1.0L. It fits into the MG, but my plan is to enlarge
the trans tunnel so I can run the exhaust through the trans tunnel to streamline the undercarriage.

For the Geo owners, what muffler should I use? I want it to be very lightweight (like everything going into this car)
I have a glasspac on the test stand, but these are actually pretty heavy mufflers.
Perhaps a motorcyle muffler? Of course, lightweight AND CHEAP, need both features!

...my first 'new' car was a 1965 MG Midget, the first year with rollup windows.

This sounds like a great project.

Is it really going to happen? No offense intended, but so many people's eyes are bigger than their stomachs when it comes to ambitious plans like this, if you know what I mean.

Are you documenting the build anywhere (web)?

For this reason I'd recommend stuffing the 1.0L in there and locating a second one to modify. That way, you'll start enjoying the car right away.

No offense taken! Typing in ideas is about 100000 times easier than getting it done in the real world!

The Midget + G10 motor is definitely building built!

Here is where we removed the stock engine,
http://www.nimblemotorsports.com/mgremove.jpg
and trial fitting the G10 motor:
http://www.nimblemotorsports.com/mgeotryfit.jpg
And here is the engine running on a stand, after I figured out the wiring!
http://www.nimblemotorsports.com/mg10stand.jpg
(IF you look to the very left, you'll see my extra engine)


The current question is whether I just put the stock motor in it now,
or do all the trick work to it for maximum efficiency, and make it a hybrid.

I have another G10 engine that I can do all the tweaks to and put this high mileage one in the car now. But once its running, THEN you ask if I'll ever really get to the tricked-out engine part! That is why I think I should do the engine work now, cause it might not get done later.

I was posting to the team swift site, but was planning to document it here instead. Of course I have my own website, and i'll show it off there once its done.

I was working on the brakes today, the stock master cylinders are toast.
I'm putting in some Wildwood cylinders and will have to tweak the pedal assembly to make them work. Pulled the stock gas tank. I want to replace it with a plastic tank to save 10-15lbs. Spent hours researching alternatives, all the race tanks are not the right size. I'm thinking of using a pair of 2.5 gallon HDPE containers ahead of the rear axles just behind the seats, which is the safest place for the gas tanks (and also move the weight inboard). I'll see if that will work once I get the containers.

This also frees up the under trunk area for some batteries.

Unless you don't have much of a work (something you do to make money) or barter/trade schedule, I'd expect this to take a while. If it were me, I'd fool around with everything you're planning on doing BEFORE you pop the engine in unless there is enough real estate in the engine bay (like the vast plains of engine bay space available in my CRXFi project) for you to have room to fiddle around with the starter motor and the TBI.

I obviously think it's a great idea for a project considering my own project inclinations :P

Depending on how broken in your head gasket is by now, I'd consider trying this out. I did it, but I don't have anything to compare it to. Others have reaped positive results.

I'll be watching this project very closely, especially if you start fooling around with replacing the TBI... definitely on my list.

Some questions: how are you going to deal with the axles? I think the midget might actually have a smaller track width than any metros and may have completely different hub/splines. MGs are RWD too, right? What are your plants to deal with these thhings fitting together?

Will: he's got a Samurai RWD transmission - it happens to bolt up directly to the stock 3-cyl engine.

And Jack: I forgot to say...

That's why we're here! Happy to have you aboard & looking forward to the project.

Samurai FD ratio = 3.73, 5th gear = .80

This makes his drivetrain (if there is only one 1.3l samurai 5spd trans configuration ever made) at cruising speed a little bit worse than an XFi and a little bit better than other garden variety g10 clones. Not too bad, but still gives my phat whip a fighting chance at beating the midget for hwy FE :p

Here's darin's stockpile of ratio information for reference by the OP.

I was wondering about ratios in the Samurai gearbox.

I'm guessing the inevitably smaller outer diameter of the tires on the Midget compared to the Samurai are going to tilt things further out of favour for low RPM highway cruising.

The Midget rear differential has a 4:10 gear, so it will have higher revs
than the XFI trans. It has 145R13 tires, pretty small, but I think the Metro has even smaller 12" tires? There is room for taller tires in back, but then they would add weight!

I actually spent a lot of time looking at tires and wheels to make them as light as possible. The bolt pattern on the Midget is not common, so
the only option is aftermarket wheels designed for the Midget which are expensive, the UltraLights. Otherwise I'd have to adapt other wheels.
It looks to me the stock steel 13" wheels are skinny and don't really weigh that much, the aluminum ones are 14 or 15, and weigh more, so I'm just keeping the stock wheels. I'm thinking moon disks on the wheels, so the appearance isn't a factor.

I love this project. ;)

I spent a small fortune on a RWA 73 1275 Midget in the early 1990s - including a whole new body shell and a 1293 racing A-Series which was superb. Not so superb was the low (17 mph/1000) gearing in 4th - not eco friendly but good for mullering the occasional Suzuki Swift GTI around at the time up to 80-ish :thumbup: and of course 'drifting' the odd roundabout.

There are quite a few K-series conversions over here - the K-series goes from a 1.1 8v, 1.4 8v, 1.6 16v, 1.8 16v and 1.8 vvc - power from 60hp to 160hp. Gearboxes vary from ford (Sierra 5 speed - aka Murkur), toyota (Celica - when RWD) and Rover (77 5 speed from the SD1 and MG RV8, Discovery etc.).

As for your engine - its an interesting idea. I kind of wondered about following down the line of the K-series conversions but going for the smaller ones - e.g. the 1.1 4 cyl 8v version (60 hp) which would have matched the original A-series 1275cc in terms of power and torque but much better for economy and much lighter.

Try Frontline for K-series, suspension, 5-speeds etc.

Good luck.

K-series being Honda engines?

(People sometimes forget that not everyone speaks the same language :) )

Whilst you are here, where's my ecomodder stickers paid for nearly 12 months ago ?

Anyhoo - no, the K-series to which I refer is the Rover one and not the Honda one - so it rotates the conventional way etc.

It can be confusing as at the time the K-series was being introduced Honda and Rover were development partners, but the Rover K is not the same. Its a very light engine with low levels of coollant etc and a sandwhich construction.

Unfortunately it also got a reputation for head gasket failure - so much so that the MGF was sometimes known as the MGHGF.

The 8v 1.1 (60hp) and 1.4 (75hp) seem reasonably reliable though.

Seriously!? ARG. That was Ben's job.

Please PM me your address and I'll send it myself, tomorrow.

Darin

Regarding drive ratios, it wouldn't surprise me if there is a ring gear mod out there for the Suzuki diff (You are using a samurai diff?

You might could go diff shopping as well, thats where I would look to get the gearing changed :-)

By the way, I just thought to add, Ive got another XFI motor pulled from a 55k car if you want another spare :-)

I ran into similar factors many, many moons ago when I did my second "non-stock" engine swap (#1: Corvair into VW): Toyota engine + trans into '64 Triumph Spitfire.

For one thing, that rear axle ratio was extremely high, so even though the Toyota 5-speed trans had a decent top gear ratio, I always wanted to reach for "another" gear when it was transplanted into the much lighter, smaller, more aero Triumph.

There wasn't room for really big tires, but I went oversize as much as possible, which must have helped a tiny increment, but was still woefully inadequate.

Then there was the wimpiness of the Triumph rear end itself. Even though I didn't engage in hooliganism, I found myself sourcing and replacing twisted-off stub axles from the crap Triumph diff. :mad: I found that I didn't enjoy that job, and dreamt of putting the Toyota rear axle in there, but that would have required major surgery i.e. frame, pan, and body... and it was becoming clear to me that the Spitfire, in spite of it's sexy styling, was a P.O.S.

WOW that three potter is HUGE!!!!!!

I grew up with the a-series in mini's, metros (BL/rover ones ;) ) Minors, Allegros Maestros and of course Midgets - Dad's Spectre white SWA '65 1293 abingdon spec and Uncles '67 teal blue 1310 RWA abingdon
and I'm amazed at the size of the 3pot'uki compared to the 4cylinder A that one's a long crank too!

Nice to see a midget getting back on the road! personally if it was over here, I'd prob got for a 105bhp 1.4 16v MPI with a sierra MT75 cogbox. That and running a mega-jolt and Mega Squirt :)

It was June - feels so long ago. Anyway PM sent.

A-series, Metros, All-aggros - happy days.

If I didn't have my BGT then an original Mini Cooper would be in my garage.

Now the kids are in boosters, i've been trying to win the missus round to the idea of another mini. She used to love my champaign beige City E ( 1308 short throw, stage 5 head kent scatter cam, duplex, HIF44 carb on a ram sock, electric fan, pointless ign -basically a surplus Autograss engine bolted into a '86 12" disc braked buzz bomb) - wish I never sold it!

She wouldn't let me have a midget - I scared her with the speed of Dad's, that and steering-by-throttle.:D

sorry - OFF TOPIC

Steering by throttle in a Mini was ace, nice drift on a wet roundabout etc etc.

All of this worked well until that incident with the dry stone wall.

EDIT : My first one was hearing aid beige. 12 inch wheels with 1275GT style hubcaps, the later ones had those silvery centre caps.

Apologies - seriously off topic now.

Just a thought on the Midget project a single-carb A-series is just about as economical petrol non-FI engine as you can get, the twin carb ones are thirsty. How about a 998, 1098 (long stroke) or a 1275 with a single carb ? The MG Metro 1275cc engine has 70bhp standard and single carb. Combine that with a 5-speed or higher axle for economy. And they have a lumpy cam so they burble nicely.

Might be less hassle than sorting out new engine mounts etc.

A carburator sucks!! And more than one sucks even more!!
The 1275 is iron and weighs 300lbs the G10 is aluminum and 150lbs.
The Suzuki G10 motor is about as long as the original 4-cyl tractor motor
that was in the car, but that is because the distributor and water outlet come out the back of the motor, adding another 6 inches to its length.

The SU's (especially the later HIF ones) aren't too bad for fuel, as far as a carb can go I suppose. Leyland claimed 80 MPG for their Metro HLE (1.0 A-Series 998 with carb) in the 80s. The MG Metro (single carb, same power as a Mini Cooper S) managed 40+mpg with care, tricky in a Cooper S.

Still the Metro (as in Suzuki) motor may be a better option if you have access to more of them :D Its just you have to change a load of stuff for FE ? High pressure piping, swirl pot etc. I tap from no experience of having done (or not done) this though.

Been working on the car, and have took apart the front, and cut out all the metal that wasn't strictly necessary. Removed 20lbs of wiring, 30lbs of front support, and 30lbs of front body. Fenders are only 20lbs, so not sure I will save much weight using fiberglass. I will be getting a fiberglass hood,
and will probably fabricate a front body/bumper/grill that will be a bit different than the stock MG for better aerodynamics.

http://www.nimblemotorsports.com/mgbarefront.jpg

A suggestion for the hood & fenders. On my old one (owned in the '70s, and still missed) they'd been bolted into a single unit, which hinged at the front, and fastened with a couple of clips by the doors. Undo the clips, and it all swung forward for easy access. Pull two hinge pins and the headlight connectors, and you could take it away as a unit, leaving complete access to the engine.

Nice work looking forward to seeing it progress. :)

...curious, just how aerodynamic were the original "bug-eye" Sprite bodies?

3 Tech Performance
3Tech may be able to help you with some performance and economy upgrades.

Did you ever consider using the 3-cyl Turbo engine?
I have been playing with the idea of putting the 3-cyl Turbo engine in a Spitfire for a while, but then can never quite decide between a 3-cyl or a small diesel.

The headlights on both the bug eye and the midget are vertical and really bad for airflow. If you remove the bug eyes, they LOOK like they flow well

http://www.speedwellengineering.com/...lkerbonnet.jpg

but then the air slams into the almost vertical windshield!
Notice that racecar has no windshield.

There are many alternative body designs for the midgets that racers used, many still available. Way too expensive for this project.
I'm actually going to make my own fiberglass trunk lid, hood, and maybe fenders, material should cost about $200-300 for all of them.

the Frog is better than the midget, slightly.

BUT they did used to race the Spridget at Le Mans in the sixties and they can up with come cool aero designs

http://www.oldstox.com/images/Sprite%202.jpg

http://www.grandprixlegends.com/Imag...s/BZ0057_1.jpg

http://www.historicinsurance.co.uk/h...allery/929.jpg

http://www.historicinsurance.co.uk/h...allery/928.jpg

...now that's a nice looking Sprite!

http://www.speedwellengineering.com/...lkerbonnet.jpg

...I likee!

How much difference does it make having no windscreen compared to one that only come up 6 to 12 inches that you see on some British cars.

Also remember that it's CdA that matters. Even if Cd isn't all that great, the fact that there's a lot less A makes up for it.

This one looks the best to me:

http://www.mgexperience.net/phorum/f...XNRockFULL.jpg

It really ends up looking more like a 912 porsche.

Another one with different front end:

http://www.mgcars.org.uk/pics/matthewssprite1.jpg

...hey, what's the passenger doing driving? (ha,ha).

I have a 1963 Midget. You can get fiberglass everything for them and get it down to around 1100#'s if you c go "all out".
A friend of mine has a 73 that he swapped a japanese market SR20DE into, pretty happy with it he's seen 48mpg on a couple trips, and at 160HP it really moves when you romp on it.