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Alfa Romeo Transaxle EV conversion ???

13K views 19 replies 12 participants last post by  PacEmaker 
#1 · (Edited)
I am brand new to this forum and am absolutely a newbie. I have a 87 Alfa Romeo Milano (Model 75 outside USA) that I'm wondering if I can convert. The car is a project anyway.

Here's where I could use some comments:

The Alfa is a Transaxle vehicle with the transmission attached to the rear axle. My thought was this if I removed the driveshaft and mounted the Electric motor in the drive shaft tunnel it would leave the entire engine bay free for batteries. Any potential problems with this?

Thought number two:
If on motor could be mounted in the drive shaft tunnel, how about two or three smaller motors in tandem? Is it possible to switch off a motor or two when not under a load and get greater range?

Maybe these questions will reveal my ignorance of the whole electric car experience but I hope you guys will tell if the transaxle Alfa presents opportunities that other donor cars don't.
 
#2 ·
Thought number two:
If on motor could be mounted in the drive shaft tunnel, how about two or three smaller motors in tandem? Is it possible to switch off a motor or two when not under a load and get greater range?
sounds like a cool car. i am pretty new myself and have not built a car yet but i think i know a bit. when thinking about mounting in the tunnel consider a couple things. one, sealing the motor against the elements but still having the space to duct proper cooling airflow. also consider your up and down travel of your axle, how are you going to connect to axle? if shorter drive line think about angle to u joint. the greater the angle the more force will be applied to the motor and bearings. if direct then your mount will need up and down or pivot travel to stay in line with the axle. as for multiple motors that sounds doable but someone with much more engineering skills will have to comment. good luck!
 
#5 ·
Mechanically, I think you would have a winner, if you have the clearance room to mount two or three 6.7 inch motors in tandum in the tunnel without them hanging below the car. As noted you would also have to take weather sealing and cooling into consideration.

You would have to mount the motor(s) to the body using a short driveshaft with flex couplings or alternativly directly to the input housing, not the sub frame and body, because the drive components are rubber mounted to the subframe. There isn't much movement between the body and the drive components, but there is enough to eventually break something.

You should look into some of the Porsche front engine EV conversions.
They may have answers about the multiple motors part of your question.

I also have wondered about tandum motors in wired to be series or parellel (that part has been done, see the Pinto and Datsun drag cars) then cut 1 or more motors out when you reach speed. Or maybe some of the more experianced members will have an answer.

I'll be following with intrest.

Jim
 
#8 · (Edited)
SunWorksco, those seem like good ideas for dropping weight in the rear. Those Alfa springs seem pretty big and heavy.. wonder why the original designers didn't think of that. Granted it was 25 years ago.

I'll have to crawl under the car and do some measurements. I'm particularly concerned that the tunnel may have more in it than the driveshaft. Gotta see how shift linkage is set up as well as the clutch linkage.

This idea of multiple motors intrigues me. I'm no physicist so I must ask, if in a two motor set up, a car is cruising slightly downhill so that only one motor is needed to maintain speed while gravity is helping, can the other motor be in regeneration mode and provide all the electricity need by the other?
 
#12 ·
Careful, the Milano/75 was designed to be 49/51 with weight distribution and Alfa always does their research very well. There is always a good reason why Alfa chooses a specific layout. If you lighten the back and make the nose heavy with batteries you're not going to have a Milano type of driving experience but a heavy understeerer, something it is not.

I have a Milano and a Spider and will do the Spider conversion instead.

Nick
 
#9 ·
Ronsd
I did much the same thing on my 924 Porsche and it has worked out OK. My original thought was to face mount the motor direct to the trans flange but I overlooked the rear suspension (torsion bar). I ended up with the motor in the tunnel just about where the original bell housing was. By the way, I deleted the clutch and the 5 speed shifts just fine. Putting 10 of the 14 batteries in the engine bay put the front axle over gross and it shows. Burying the motor in the driveshaft tunnel created cooling and service problems.
As far as multiple motors, I doubt the advantage. First of all motors, even small ones are expensive. Why double or triple your investment? Second, driving the car down the road at a speed requires a certain amount of power (in my case about 8KW @ 40 mph) which will be constant whether it comes from 1,2 or 3 sources. In addition, I wonder how you could control multiple motors. Big disconnects? Multiple controllers? You might have an idea on this but the thought makes me cringe. Good luck.
tommyt
tommyt
 
#10 · (Edited)
Tom,
Looks like it taken the EV movement to get an Alfa guy and a Porsche guy talking to each other. ;) It's a good thing!

I knew that the front-engine Porsches had a similar transaxle set up and it's great to see you've already done the conversion. Your comment about the clutch resolves one question for me...clutch will go.

How did you resolve the cooling issue? What motor are you using? How's your range and speed? I don't need more than 40 miles but would like to be able to keep up with freeway traffic.

As to multiple motors, I'm coming to a realization that might be more trouble and cost than any benefit derived.

I should add that my goal is to keep the same weight balance of 51%/49% as the handling is why I love this car.
 
#11 ·
Ron
I am using a D&D 15ES6 motor which is a 6.7" series wound. The cooling issue has not yet been handled despite propping the hood open abt 4" to act as a big air scoop. In fact, I may have damaged the motor irrepairably; it appears that one of the commutator bars may have lifted. The next step is to remove the motor which is a major chore.
I think you may be optomistic in your range & speed expectations. Although I have had the Porsche up to 60mph it was only for a few seconds and not sustainable. At more reasonable speeds (35-40), range is around 25-30 miles. Batteries are the key and my thousand pounds of lead/acid are not quite up to the task.
tommyt
 
#13 · (Edited)
Hello from a long time lurker but first time poster, greetings from Finland!

I know this is an old thread, but it seems that there are not many that have done conversions on alfa's tranaxle design, and I thought maybe more info could be kept in the same thread.

Anyway, long story short: got myself a 75 TS, which is a really nice car, and then I could not let a deal on two more of them pass by so now I've got three of them.. A lot of the soul in an alfa comes from the engine, but the design still makes it look like it woud be an ideal car for a DIY conversion. With the gearbox in the back and a LSD in the back of it. Unfortunately it looks like mounting motors in the tunnel would be a tight fit, the diameter of the tunnel is ca: 20cm and the axle shares space with the gearbox linkage.
So, if anybody has info on a conversion of this sort, please let me know.
Pictures:
https://www.dropbox.com/sh/pahx4z5mcdnh5t7/AACS6AGAG-muWpnDGnPjRbSFa?dl=0
 
#14 · (Edited)
I have an '85 GTV6 that I been "saving" for an EV project for the last 10 years. I have loved Alfas since I was a little kid. I've also been into EVs since the mid 90s. Needless to say, I have been thinking about this Alfa for some time.

Your Milano is a similar car, it had the same drivetrain, but in a slightly bigger car, which is a sedan. Still performance-oriented, and relatively light for a "saloon".

Engine up front, transaxle in the rear, with a goofy driveshaft and rag joints running down the tunnel. This tunnel is not very big, so your interesting idea about sticking the motors in the shaft tunnel may not work out like you want.

A brace, or even a trio, of smaller motors will probably not give you the torque you need. For starters, a motor's diameter dictates its leverage on the shaft, much like an ICE's crank throw. You'll probably want at least a 9" motor, or even and 11-incher. Hooking the motors up longitudinally is no easy task either. I know this because I'm putting twin AC-50s into my current EV, a '53 Hudson Hornet (for TWIN E-POWER!).

I believe you also mentioned something about setting one motor in regen mode to power the others -- this is something called "perpetual motion". Unless one has mastered witchcraft, perpetual motion is completely impossible. You simply cannot generate more power than you're using without breaking the laws of thermodynamics...and the laws of thermodynamics are unbreakable without copious amounts of very advanced magicks, lol.

My advice is to get yourself a stout 9 or 11" motor, and place it into the spot once occupied by your old, beautiful, melodious 6-cyl Alfa engine. Your Milano will benefit greatly by a clean *reliable* powerplant. There will still be plenty of room for batteries, especially if you only need a 40-50 mile range. You should be able to distribute the batteries to keep the chassis balanced, if you desire. I had HPEV's AC-35* dual motor in the plan for my GTV6, but I've decided to do my Hudson instead, it's more suitable for my family. * (it's two AC-35s on the same shaft, so you don't have to mess with a coupler):cool:

I hear Kia SoulEV batteries are pretty light for the power, as are Chevy Volt and Nissan Leaf modules. Tesla modules are supposed to have a great power:weight ratio, but they can be kind of unstable and expensive.

Good luck! BV

*I didn't realize this was such an old thread...I wonder if he ever built this car...I still have GTV6...maybe I'll do it after my Hudson if hit the Lotto, lol!
 
#15 ·
Ease of installation is for sure a factor. One would have to redo the tunnel where the, prefferably single, motor would sit. Also, in building motor and battery mounts I will have to learn to weld.. Still with a modified tunnel it would not be flush with the bottom of the car, I suppose I have to forget about that idea.

As for the sonorous sound, I could keep the v6 as is and convert one of the TS:s . Unfortunately, scrapped EVs are few and far between here with regards to batteries. Another possibility is to start collecting 18650 when one could get them for free, but I suppose I would need a couple of thousand cells..
Also, heat in the winter is an issue, I recently sold my diesel as it just is not nice to use when it's cold.
Hmm, lets see if there are any forklift scrapyards nearby.
 
#16 · (Edited)
Very cool car.

You are probably better off just using a driveshaft and putting the motor(s) in the front. I also had dreams of hiding motors in the transmission/driveshaft tunnel, but in the end I decided against it. It would severely limit what size motor you can use, especially if you may wish to upgrade to a different motor in the future, plus it would be a pain to service them. Unless you do not mind cutting up the transmission tunnel, which I think would be a shame, especially for a rare vehicle. Electric motors do not take up as much room as an engine. You can still fit batteries above and around them.
 
#17 · (Edited)
The layout of this car is very unique (engine up front, torqueshaft down the tunnel, clutch and transaxle in the rear), and it's a big reason this car would make a great EV. You don't need to do a conventional adapter plate to the trans and mess with clutches, flywheels, or transmission shafts. Just mount the motor up front and send the torque down the shaft like the ICE did. Motor mounts shouldn't be too weird since the ICE had its own engine mounts.

Speaking of the ICE...yeah, most of us get it...many of us loved ICEs and their associated sounds, noises and melodies. Some EV drivers hate cars, and those guys usually drive store-bought EVs, or convert something that was a waste of metal to begin with. Here, most of us really like cars, and many of us were gearheads/petrolheads before we woke up to whatever got us interested in EVs.

So, yeah, Alfas sound really cool...when they actually run (I've had two of them, so I can speak to their unreliability). Guess what? Performance EVs sound really cool too, and they have their own cacophonies. From a subtle turbine whine, to sounding like an angry TIE Fighter from Star Wars, to the raucous of an Formula-E that sounds like a Banshee with a hangover...high performance EVs can be pretty rowdy too, mate!

Just build what you like, what you'll actually drive. A car in the garage, or worse yet, rusting away in a scrapyard (or a barn) is useless.

Why concern yourself with "cutting up" a rare car? Chances are, if you don't breathe new life into it as an EV, it'll probably die a miserable lingering death by rust anyway. Most young kids aren't really into cool old cars, and the older folks have a shortlist of what they think is cool...I'm so sick of seeing the same 6 car models at car shows over and over. Alfas are certainly awesome cars, but nobody is fighting over them. The ICE you remove may actually help some Alfisti somewhere!...or the gas tank, the radiator, any smog controls, etc...
</rant>
 
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