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Clev · 02-04-2011, 10:48 PM

It's not a matter of tastes, it's a matter of practicality. There's no advantage to having the motor in the rear. If you're putting the motor in the rear because you think shorter cabling means more efficiency, you're in for a real surprise when you try to do an emergency lane change with the motor and all your batteries in the rear. At least with everything in the front you'll get predicable understeer.

But just to humor you, here's what's involved with each of your choices:

1. AWD Eclipse. You're going to throw out the drivetrain and couple the motor/tranny directly to the rear diff, I assume. That means that you'll have to mount the motor/tranny to the suspension as unsprung weight; otherwise, there will be no provision for the motor to move relative to the suspension. (On RWD cars, the driveshaft takes care of this; on FWD cars, it's the CV shafts.) Throw a 200 pound motor and 125 pound tranny on your suspension as unsprung weight, and you'll probably crack a rim every time you hit a pothole.

2. CRX. You might be able to adapt the FWD transmission to the rear. You'd have to swap the ring gear so you don't end up with five reverse gears and one forward. You're also cutting out a big chunk of the floor to fit the motor/tranny package in there, adapting drive axles and rear suspension from an AWD Civic to fit. And then you have no room for batteries in the back at all.

3. BMW 8-series. The 840s only came with autos, so you're looking at an 850i. The 6-speed is pretty rare, so you're going to pay $15,000 for a 1991 model, cut up the floor and weld in motor/tranny mounts, put all of the weight in the rear for "drivetrain efficiency", and end up with a slow porker (base weight is over 4,000 pounds) that can't accelerate (it got 0-60 in 7.2 seconds with a freaking V-12) or corner (all of the weight in the back for driveline efficiency), and you'll end up selling it for less than half you paid, since nobody wants a Bimmer that somebody's hacked up, and you find out there's no thrill in a 8 series that goes 0-60 in 35 seconds.

02-04-2011, 10:48 PM	#11 (permalink)
Clev Wannabe greenie Join Date: Aug 2008 Location: Yorba Linda, CA Posts: 1,098 The Clunker (retired) - '90 Honda Accord EX sedan Team Honda 90 day: 29.49 mpg (US) Mountain Goat - '96 Ford Ranger XLT 4x4 SuperCab 90 day: 18 mpg (US) Zippy - '10 Kymco Agility 125 90 day: 65.03 mpg (US) Thanks: 5 Thanked 53 Times in 40 Posts	It's not a matter of tastes, it's a matter of practicality. There's no advantage to having the motor in the rear. If you're putting the motor in the rear because you think shorter cabling means more efficiency, you're in for a real surprise when you try to do an emergency lane change with the motor and all your batteries in the rear. At least with everything in the front you'll get predicable understeer. But just to humor you, here's what's involved with each of your choices: 1. AWD Eclipse. You're going to throw out the drivetrain and couple the motor/tranny directly to the rear diff, I assume. That means that you'll have to mount the motor/tranny to the suspension as unsprung weight; otherwise, there will be no provision for the motor to move relative to the suspension. (On RWD cars, the driveshaft takes care of this; on FWD cars, it's the CV shafts.) Throw a 200 pound motor and 125 pound tranny on your suspension as unsprung weight, and you'll probably crack a rim every time you hit a pothole. 2. CRX. You might be able to adapt the FWD transmission to the rear. You'd have to swap the ring gear so you don't end up with five reverse gears and one forward. You're also cutting out a big chunk of the floor to fit the motor/tranny package in there, adapting drive axles and rear suspension from an AWD Civic to fit. And then you have no room for batteries in the back at all. 3. BMW 8-series. The 840s only came with autos, so you're looking at an 850i. The 6-speed is pretty rare, so you're going to pay $15,000 for a 1991 model, cut up the floor and weld in motor/tranny mounts, put all of the weight in the rear for "drivetrain efficiency", and end up with a slow porker (base weight is over 4,000 pounds) that can't accelerate (it got 0-60 in 7.2 seconds with a freaking V-12) or corner (all of the weight in the back for driveline efficiency), and you'll end up selling it for less than half you paid, since nobody wants a Bimmer that somebody's hacked up, and you find out there's no thrill in a 8 series that goes 0-60 in 35 seconds. __________________