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Looking to get educated on taking a FWD car and making it RWD as part of a conversion. This is not a current build, just something I am kicking around so please don't hang me.



Looking at FWD car (Pontiac G6 coupe) where the engine is currently transversely mounted. I believe the "simple" and more straightforward or traditional approach would be to mount a suitably sized motor to the existing transaxle. From what I can see something like a dual AC-35 would work nicely (its about 19" in length where the current is around 25" / the trans is rated to handle the HP and torque outputs). Then just find somewhere to cram all the batteries and other components.



I am very unfamiliar with making a FWD into RWD. The complexity of it is not lost on me. One possible method could be to use a Tesla rear subframe, correct? Essentially swapping that for the existing. As long as you can make the dimensions work then you could use a Tesla drive unit. If a different rear subframe is a better dimensional fit than the Tesla, the same approach could work? Modifying the existing rear to allow for the drive unit seems out of the question as its probably more complex than swapping for an appropriate RWD subframe (?).
 

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It's worth investigating whether the mounting points for the rear suspension/subframe are the same in your FWD car as a RWD or 4WD car from the same company. Modifying a RWD subframe to add a motor mount has to be easier than creating a completely custom subframe.
 

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I agree with Emyr... and even in a car which is fundamentally front-wheel-drive but has an optional AWD version, a complete drive unit (motor and transaxle) is unlikely to fit where the factory final drive unit (just a differential and ring-and-pinion gear in a box) sits. If you put the motor up front and keep the original rear drive components from an AWD, then there is little space left for battery. None of this would work for the G6 anyway, because there was not an AWD version, and I don't think the G6 rear suspension can accommodate conversion to a driven axle.

If just swapping the engine for a motor on the original transaxle, I hope the transaxle is a manual. The G6 and related models did have a manual transmission available, but most will be automatics.

Dropping an entire EV drive unit complete with subframe and suspension into the rear of a vehicle which was not already rear-engine or mid-engine typically means major body surgery... although if done well the result can work well. Even if by some miracle mounting points essentially lined up, the drive unit with suspension will be much more bulky that the suspension that was originally there.
 

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I have done something similar in the dim and distant past

The "easiest" way to do this is to cut away most of the rear of the car and them make a tubular subframe to transfer the operational loads into the rest of the car

Not actually that difficult but it does involve some "courage" and it's not reversible!
 

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Discussion Starter #5
Thanks all! The G6 was FWD only. Other cars on the same platform did have AWD options but I am not going to pursue this route any further right now. Maybe sometime in the future once I have more experience. A RWD G6 with a tesla drive unit would FLY! If I ever do it, it would be a racing application and I would probably remove the rear seat leaving plenty of room in the back.



As for just planning a FWD EV conversion. I would like to find a manual but a majority made were automatic. Not to start that discussion here, but I have been reading other threads discussing use of automatic trans in conversions vs manuals. Trying to get smart. Automatic should still work, just more required to keep it lubricated and what not. Again manual preferred.
 

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As for just planning a FWD EV conversion. I would like to find a manual but a majority made were automatic. Not to start that discussion here, but I have been reading other threads discussing use of automatic trans in conversions vs manuals. Trying to get smart. Automatic should still work, just more required to keep it lubricated and what not. Again manual preferred.
As you said, the details are in other discussions, but throwing away an automatic, buying a manual from a salvage yard, and fitting the manual into the car will likely be much less work and much cheaper than making an inappropriate automatic work. That's all assuming that you use an original transaxle at all.
 
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