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Why AWD? Plowing snow?

Don't need it for 4+ sec 0-60 on street tires.
Maybe for better handling?

Ditch it, put a Tesla SDU up front (in back will F up the balance of the car), batteries in the tunnel and rear seat area. Transmission takes up too much space & weight.
A Tesla SDU won't likely fit in a CRX without reversing its position, to avoid hitting the firewall.
There is no tunnel in a CRX... unless for "battery" you're thinking of something like a single string of D-cells. ;)
A CRX has no rear seat, exceptionally optionally in Japan where a bit of padding is optionally available for small children. Where the rear seat base would be is a small storage bin... that's good for about 1 kWh of battery.

But yes, a multi-speed transmission is unnecessary weight and bulk in a car which is too small for the conversion.
 

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@windraver oh geez that's bringing back memories. I had an '86 with louvers. Should have never got rid of it. Also had an '87 Hatchback. Currently have '05 Si hatch.

@brian_ AWD will make handling worse because it will increase weight. It will make traction better for acceleration only otherwise the car will be the same or slightly worse in handling department.
 

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Discussion Starter · #23 ·
Nice! Looking forward to seeing your project!
My build: wind's pop-up 86 Si (Android Auto and Picture Day)
Hey, a CRX community member! :) I'm 2point2 on there.

Super nice first gen! the ONLY car i've ever liked rear window louvers on.

There's enough DNA in the 2nd gen CRX to cobble together RT4WD, from the steering wheel forward it's like any other B or K swap ;). There was a 4th gen civic wagon with a very simple version of RT4WD.

I have a 200whp Civic and 320whp Miata. I also think FWD is just fine for the eCRX!
My crx had 400whp (400.3 to be exact). At all power levels I've had over the years there was never a time I didn't wish I had better traction. :unsure:
 

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@brian_ AWD will make handling worse because it will increase weight. It will make traction better for acceleration only otherwise the car will be the same or slightly worse in handling department.
If only vehicle dynamics were that simple: more weight = poorer handling. Rear drive (by shaft, or by small rear drive units in some hybrids) are used in vehicles which are primarily front wheel drive for traction in very poor traction conditions or extreme acceleration, but also to shift some drive force to the rear to reduce excessive oversteer. The likely shift of mass rearward due to the battery location will make the front wheel drive even worse for handling; adding rear drive could help, if properly done.

I agree that excessive mass, bulk, complication, and cost, are concerns with AWD, and that it isn't needed for acceptable handling.
 

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Rear drive (by shaft, or by small rear drive units in some hybrids) are used in vehicles which are primarily front wheel drive for traction in very poor traction conditions or extreme acceleration, but also to shift some drive force to the rear to reduce excessive oversteer.
Rear drive increase tendency to oversteer on acceleration.
The likely shift of mass rearward due to the battery location will make the front wheel drive even worse for handling; adding rear drive could help, if properly done.
Definitely not. Making the weight distribution closer to 50/50 front/rear will make the car handle better. On FWD racecars negative rake is used which lowers the rear end of the car and lifts the front which causes the weight balance to shift rearward which increase stability under braking and in transitions...you know handling.
 

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Rear drive increase tendency to oversteer on acceleration.
If overdone, yes. If drive is distributed reasonably, driving all tires instead of just the front reduce the tendency to understeer on acceleration.

Definitely not. Making the weight distribution closer to 50/50 front/rear will make the car handle better. On FWD racecars negative rake is used which lowers the rear end of the car and lifts the front which causes the weight balance to shift rearward which increase stability under braking and in transitions...you know handling.
If you think that a couple of degrees of rake meaningfully changes the mass distribution you need to "do the math", as they say. But yes, any very front-heavy car will generally handle better under braking with an actual mass distribution shift rearward, despite the reduction in drive traction (and the resulting worsened power understeer); an EV conversion will typically result in a rearward mass distribution shift if the majority of the battery is located in the rear half of the car, rather than around the front axle. Those are reasons to shift to a more neutral distribution and to drive all of the wheels, not a reason to avoid AWD.
 

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If overdone, yes. If drive is distributed reasonably, driving all tires instead of just the front reduce the tendency to understeer on acceleration.
You said Oversteer first, now you are changing to Understeer?
but also to shift some drive force to the rear to reduce excessive oversteer.
Which is it?
If you think that a couple of degrees of rake meaningfully changes the mass distribution you need to "do the math", as they say. But yes, any very front-heavy car will generally handle better under braking with an actual mass distribution shift rearward, despite the reduction in drive traction (and the resulting worsened power understeer); an EV conversion will typically result in a rearward mass distribution shift if the majority of the battery is located in the rear half of the car, rather than around the front axle. Those are reasons to shift to a more neutral distribution and to drive all of the wheels, not a reason to avoid AWD.
It's called corner-balancing and yes it makes a big difference. That's why it's done.
 
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