[eBEEMER]

I am a complete newby but here goes:- My issue is finding reliable info to be able to decide on an effective transmission arrangement.:-
The project is a BMW 2002. (about 1400kg converted) I could use a manual or automatic gearbox with or without a clutch and flywheel or bypass both and connect directly.
The motor is a 20/87 kW 350 Amp brushless dc
I can reverse the motor, so don't necessarily need a reverse gear.
I have also been told that regenerative breaking will not work with an automatic box.
I understand that auto gearboxes are less efficient than manuals, but can't find any reliable info on how less efficient. The Kansas EV powerglide or something similar might be the answer. So, lots of options.
If anyone has trodden this path before and found a workable, lightweight soloution, that would be very helpful.Thanks

[SHtruck]

Originally Posted by eBEEMER

I have also been told that regenerative breaking will not work with an automatic box.
I understand that auto gearboxes are less efficient than manuals, but can't find any reliable info on how less efficient.

Like on KansasEV design, if there's no torque converter, regen will work. And if there were TC, regen would work if there TCC is locked (TCC = torque converter clutch).

Without TC, automatic is as efficient as the manual, because it's the slippage of the TC that makes autos less efficient. But that depends on make and model and how the automatic is controlled. Old school autos are less efficient than modern ECU controlled ones.

[mizlplix]

A gearbox is a gearbox.

Regen WILL work with a torque converter. All regen has a parameter setting to set a taper off low speed requirement, so you dont just regen down to a dead stop. So a decent torque converter will regen down to the stall speed where the controller cuts off anyways.

Miz