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3 Posts
Hi, my name is Pete, and I am in UK.
I have a Renault Kangoo ZE, and have done 20k miles of very pleasant miles in a hilly area. I have owned lots of cars in the last 51 years of driving, none were nicer to drive than the Kangoo.
I am pondering converting a Triumph Spitfire and have a question about low speed acceleration.
I have done the sums on aero drag, car mass etc and figured out the best option is probably a AC50 and a Curtis 1239 and 144v. I could possibly get away with a AC34.
Every EV I have looked at seems to mount the motor on the old car gearbox, I am unsure why.
The car final drive ratio is 3.66:1 which gives top gear spread of 16.7 mph at 1000 revs. So 50mph is 3000 revs. The AC50/1239 torque curve is flat all the way to 4000 revs.
My understanding is that as the torque is pretty well constant over the urban speed range, there should be zero benefit in using high revs to pull away.
I am wondering if I really need to keep the gear box, as it just seems to be a 80lb mounting bracket. It looks like it is easier to machine a motor flange that bolts direct to the prop shaft UJ. This would allow the motor to sit where the gear box went. This both reduces weight and frees up space for batteries. OK I will have to fab more mounting brackets and I may not be able to push the motor in exactly the old gear box position.
So folks, here is my question, does anybody out there have figures for acceleration in different gears using an AC34/50 motor.
Pete
I have a Renault Kangoo ZE, and have done 20k miles of very pleasant miles in a hilly area. I have owned lots of cars in the last 51 years of driving, none were nicer to drive than the Kangoo.
I am pondering converting a Triumph Spitfire and have a question about low speed acceleration.
I have done the sums on aero drag, car mass etc and figured out the best option is probably a AC50 and a Curtis 1239 and 144v. I could possibly get away with a AC34.
Every EV I have looked at seems to mount the motor on the old car gearbox, I am unsure why.
The car final drive ratio is 3.66:1 which gives top gear spread of 16.7 mph at 1000 revs. So 50mph is 3000 revs. The AC50/1239 torque curve is flat all the way to 4000 revs.
My understanding is that as the torque is pretty well constant over the urban speed range, there should be zero benefit in using high revs to pull away.
I am wondering if I really need to keep the gear box, as it just seems to be a 80lb mounting bracket. It looks like it is easier to machine a motor flange that bolts direct to the prop shaft UJ. This would allow the motor to sit where the gear box went. This both reduces weight and frees up space for batteries. OK I will have to fab more mounting brackets and I may not be able to push the motor in exactly the old gear box position.
So folks, here is my question, does anybody out there have figures for acceleration in different gears using an AC34/50 motor.
Pete