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Hi All! Newbie here v keen to build an EV. Currently drive MB E350 estate & fed up of 80L diesel fill ups!
I have always loved the Fiat Coupe(1993-2001) & would love to electrify one as a daily driver & keep E350 for 'hauling'.
Positives are; they are relatively light, aerodynamic, fwd with transverse engine. Can be picked up as non runners for not too much.
However, i am unsure about negatives! I have concerns about storage for adequate batteries(I wish to retain rear seats). I'm not sure about the ECU & electronics- are they retained or dumped & how far can they be integrated with an electric system? Any feedback & advice plus electric drive train suggestions would be greatly appreciated 馃榿
 

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This isn't specific to the Fiat Coupe (I've never even seen one except online, as they were never sold here), but with any transverse-engine front-wheel-drive car, there is now the possibility of using a complete drive unit (motor, gearbox, differential) salvaged from a production EV to replace the engine and transaxle. There are lots of factors to consider, but it is now an option.
 

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This isn't specific to the Fiat Coupe (I've never even seen one except online, as they were never sold here), but with any transverse-engine front-wheel-drive car, there is now the possibility of using a complete drive unit (motor, gearbox, differential) salvaged from a production EV to replace the engine and transaxle. There are lots of factors to consider, but it is now an option.
Hi Brian, thanks for the reply. I was aware that the transverse engine meant slightly more efficiency, but your suggestion is very interesting. Would this route be much more complicated than bolting motor straight onto clutch? Can you give any pointers or suggested units please? Many thanks
 

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I was aware that the transverse engine meant slightly more efficiency, but your suggestion is very interesting. Would this route be much more complicated than bolting motor straight onto clutch?
The complications are different. By using a complete drive unit, you wouldn't need to do any of the work of finding or making an adapter plate to mount a motor to a transaxle, or a coupler to connect the motor shaft to a transaxle input shaft, and no clutch is required... but you would need to mount the drive unit to the vehicle (and the mounting points on the drive unit won't line up with the corresponding points on the vehicle structure), and axle shafts are needed which work with the drive unit on the inboard end and the vehicle's hubs on the outboard end. The complete drive unit has a matched controller/inverter, but you would need to work with the stock programming and control system... which is a large subject by itself.

Can you give any pointers or suggested units please? Many thanks
Only the Tesla Model S/X and Nissan Leaf are somewhat popular choices for this approach, because there is more knowledge of their control systems... but one builder just did this with a Chevrolet Bolt drive unit (see Westfalia T3 with Chevy Bolt drivetrain). To fit in the car reasonably, a drive unit which places the motor ahead of or on the axle line is needed; that means almost any EV except a Tesla.
 

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The complications are different. By using a complete drive unit, you wouldn't need to do any of the work of finding or making an adapter plate to mount a motor to a transaxle, or a coupler to connect the motor shaft to a transaxle input shaft, and no clutch is required... but you would need to mount the drive unit to the vehicle (and the mounting points on the drive unit won't line up with the corresponding points on the vehicle structure), and axle shafts are needed which work with the drive unit on the inboard end and the vehicle's hubs on the outboard end. The complete drive unit has a matched controller/inverter, but you would need to work with the stock programming and control system... which is a large subject by itself.

Can you give any pointers or suggested units please? Many thanks
Only the Tesla Model S/X and Nissan Leaf are somewhat popular choices for this approach, because there is more knowledge of their control systems... but one builder just did this with a Chevrolet Bolt drive unit (see Westfalia T3 with Chevy Bolt drivetrain). To fit in the car reasonably, a drive unit which places the motor ahead of or on the axle line is needed; that means almost any EV except a Tesla.
Thanks again for the extra info.
The Boltfalia thread is interesting but rather daunting.
With no engineering or programming background or facilities, the complete drive unit- whilst superficially sounding simpler(& a better option)- is likely to be more complex for me. I would likely need a whole donor car & then need engineering facilities plus fixing the firmware post crash. Bracket would be straightforward, but not sure about the driveshafts, which sound complex & prone to pitfalls. Who would one go to in the uk to sort that out?
For just an average, moderately handy chap, the motor bolted onto clutch is likely to be the route taken, unfortunately. Who is best place to go to for the clutch adaptor plate, please?
 

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The simplest is not the motor bolted onto the clutch but the motor simply driving the propshaft

Throw away the engine and the gearbox

That then needs a fairly grunty motor - an 11 inch forklift motor would be about right
 

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Discussion Starter #7
The simplest is not the motor bolted onto the clutch but the motor simply driving the propshaft

Throw away the engine and the gearbox

That then needs a fairly grunty motor - an 11 inch forklift motor would be about right
Hi Duncan,
Yes i agree that would be simplest, but I would like regen braking, so understand AC is better for this. Doesn't keeping the gearbox allow more choice & range of road speeds? Thank you
 

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The simplest is not the motor bolted onto the clutch but the motor simply driving the propshaft

Throw away the engine and the gearbox...
Duncan, how would you suggest that someone does this with a Fiat Coupe, which is front wheel drive? There is no propeller shaft, and no separate final drive.

In any workable design, there will be reduction gearing between the engine and the axles; with no separate final drive if the Fiat Coupe gearbox is discarded something would need to replace it.
In any single-motor design for a vehicle with two driven wheels, there must be a differential; if the Fiat Coupe transaxle is discarded something would need to replace the differential in it.

I suspect that Duncan missed the configuration of the Fiat Coup茅 (type 175), and is thinking of an earlier RWD model such as the Fiat 124 Sport Coup茅.

So the original statement is correct: the simplest installation mechanically is to adapt a motor to the car's original transaxle.
 

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... I would like regen braking, so understand AC is better for this.
The benefit of regenerative braking in DIY projects is hotly debated, but yes... you need AC (or at least a DC motor with separately excited field winding) for effective regenerative braking.

Doesn't keeping the gearbox allow more choice & range of road speeds?
You need reduction gearing, because no reasonable motor will be suitable to drive the vehicle by running at wheel speed. If your motor and battery combination can deliver enough power over a wide enough range of speeds, a single ratio works fine (and that's how essentially all production EVs work). In vehicles such as Duncan's, a final drive unit (differential and ring-and-pinion gears in one housing) salvaged from the rear of a production rear wheel drive or all wheel drive vehicle provides one stage of gear reduction, with a ratio of roughly 3:1 to 4:1 (which is not enough reduction for a high-speed motor, but usually suits a traditional brushed DC motor well).

Yes, most DIY projects which don't use salvaged production EV motors don't have enough motor speed range, so they benefit from having more than one reduction (gear) ratio.
 

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Thanks again for the extra info.
The Boltfalia thread is interesting but rather daunting.
With no engineering or programming background or facilities, the complete drive unit- whilst superficially sounding simpler(& a better option)- is likely to be more complex for me. I would likely need a whole donor car & then need engineering facilities plus fixing the firmware post crash. Bracket would be straightforward, but not sure about the driveshafts, which sound complex & prone to pitfalls. Who would one go to in the uk to sort that out?
For just an average, moderately handy chap, the motor bolted onto clutch is likely to be the route taken, unfortunately. Who is best place to go to for the clutch adaptor plate, please?
Have you heard of Zero EV?
https://zero-ev.co.uk/ev-conversion-kits/
Maybe worth a look for kits, ideas, etc. It is what I am pondering about at the moment as a (nearly) drop in drive unit for my old Skoda Octavia.
 

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Discussion Starter #11
Hi MoTs, i had not yet come across this site, but it looks good & they sound professional, so i will definitely be making enquiries thank you!
 

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To fit in the car reasonably, a drive unit which places the motor ahead of or on the axle line is needed; that means almost any EV except a Tesla.
Hi Brian,
Please would you tell me why Tesla units are no good?
I wondered about fitting a front Tesla motor.....?
Thanks in advance
Matt
 

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To fit in the car reasonably, a drive unit which places the motor ahead of or on the axle line is needed; that means almost any EV except a Tesla.
Please would you tell me why Tesla units are no good?
I wondered about fitting a front Tesla motor.....?
The problem is simply that a drive unit is only likely to fit if the motor ends up in roughly the same place as the original engine. This car, like almost every transverse-engine design, has the engine just ahead of the axle line, but the Tesla Model S and X drive units (front and rear) place the motor just behind the axle... and there it will likely conflict with structure (and, in the case of an installation in the front, the steering rack).

The Tesla Model 3 rear drive unit and the Tesla-supplied drive units for the RAV4 EV and perhaps other models of other brands do place the motor ahead of the axle, so are more likely to fit.
 
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