# miles/kwh to amp hours per mile.



## gojo (Feb 1, 2011)

"The Leaf appears to get about 3.5 miles/kwh in normal
driving."

I am interested in how my RX7 conversion compares to the Leaf. I usually use between 2.1 and 2.4 amp hours per mile, can someone explain how that would compare to 3.5 miles per/kwh.


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## major (Apr 4, 2008)

gojo said:


> "The Leaf appears to get about 3.5 miles/kwh in normal driving."
> 
> I am interested in how my RX7 conversion compares to the Leaf. I usually use between 2.1 and 2.4 amp hours per mile, can someone explain how that would compare to 3.5 miles per/kwh.


For approximation, multiply 2.25 Ah/mile times your nominal pack voltage and take the inverse. Result is miles per Wh so multiply by 1000 to get miles per kWh. ie. 2.25 Ah/mile * 100V = 225 Wh/mile. Inverse = 0.00444 miles/Wh = 4.44 miles/kWh.


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## gojo (Feb 1, 2011)

Hey, Thanks. 2.25x120v=270
Inverse ='s 0.0037 X 1000=3.7 miles/kwh

So the Leaf doesn't have anything on the RX7 conversion when it comes to miles/kwh.

You made my day.


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## Guest (Oct 10, 2011)

I get 3.8 to 4.2 miles per KWH in my Leaf. Right in line with most all conversions using lithium. Have a wonderful day. You have done well to get that kind of mileage. 

Pete


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## EVfun (Mar 14, 2010)

First off, thanks for the quick conversion. It makes perfect sense, figure watt hour per mile, inverse to make it miles per watt hour, then multiply by 1000 to make it miles per kWh. 

So the Leaf is running at about 250 watt hours per mile, very respectable performance. It's kinda sad that my 1100 lb. buggy is only slightly better at 200 watt hour per mile (5 miles per kWh.)


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## Guest (Oct 10, 2011)

EVfun said:


> First off, thanks for the quick conversion. It makes perfect sense, figure watt hour per mile, inverse to make it miles per watt hour, then multiply by 1000 to make it miles per kWh.
> 
> So the Leaf is running at about 250 watt hours per mile, very respectable performance. It's kinda sad that my 1100 lb. buggy is only slightly better at 200 watt hour per mile (5 miles per kWh.)


Yes, very respectable performance. If you have a chance some day to change out your Ring and Pinion you might get better watt hours per mile if you do. I purchased my ProStreet transaxle with 3.44:1 Ring and Pinion for the Bus. I hope it helps a great deal. You do have and open vehicle. What speeds are you driving to get your 5 miles per kWh? I drive mine at 55 to 65 mph. I did a good run today at 52 mile per hour and got slightly better mileage than I do at 62 mph. So for the little I gain I have decided to just drive like I normally do and not drive like a slow poke to gain a few extra miles per charge. It's not worth the hassle. I have plenty no matter what. 

Pete


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## EVfun (Mar 14, 2010)

200 watt hours per mile is general city driving. Around here that means mostly 35 mph roads with traffic at 40 mph and some roads up to 45 mph. I don't do a lot of freeway but power consumption jumps by about half to something around 300 watt hours per mile. Those front fenders are basically parachutes in a beach buggy. The windshield is tall and steep, and then there is the whole open vehicle issue.

I understand that Jack didn't want to do any more testing because he had no plans to replace either transaxle. Still, I wish he would find the interest to dyno test the 2 side by side or at least run the 2 vehicles on the same course and speed and compare gear oil temperatures. The R&P looks like the most likely cause, but it was never really nailed down. Going to the aftermarket 3.44:1 is quite a bit more expensive than using one of the factory R&P sets. I currently have a older Transform faux close ratio box, 4.375 R&P with the 0.93 Super Beetle 4th gear (the rear tires are almost 27 inches tall.) There is noticeable deceleration drag, I test this at the end of a local freeway. My wife's Yaris refuses to loose speed and would go through the light at 55 mph still. My Tacoma looses speed and goes through the light at 40 mph. My Buggy looses speed to the point where I get back on the throttle before the light (gets down to 35 mph.) I don't know how much of this is wind losses and how much is mechanical. I know the buggy will slowly roll out of my garage if I don't set the parking brake. It rides on ball bearings on all 4 corners. There are low rolling resistance tires on all 4 corners (but *each* rear tire is rated 500 lb. more than the entire vehicle weight.)

I look forward to seeing your results with the 3.44 R&P. I plan to do a little work to my buggy over the winter, mostly rebuilding a very loose 47 year old front suspension. I will hopefully have some better results to compare with.


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## Guest (Oct 10, 2011)

I will keep every one in the loop with the Bus conversion. Soon will be taking it in for a little more body welding and prepping it for paint and interior. Front disk brakes coming soon. Just gathering parts before putting it all together. I will be doing some controller tests before we paint the Bus. I will be placing the batteries in boxes in the cargo area first. I plan on 200 AH or better down the road to try to get a Bus that will have a true 150 or better miles per charge at 55 mph. I want the bus to be a long range bus and not a hot rod. I expect it to be pretty damn quick but not race quick. That is our goal. I hope the Older Kostov will handle the 156 or 190 volts I plan on putting into the project. I may need to go with a new HV motor. Not sure if I will stay with Kostov or move over to Warp11 with interpoles. 

Pete


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## EVfun (Mar 14, 2010)

Is that the older 10.7 inch Kostov with interpoles and a rather noisy fan? I know Plasma Boy ran one of those up to about 200 volts. He did eventually loose it but he kept running 1000 amps through it. It got the White Zombie down into the low 13's. I was at the track when he blew it back in 2000.


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## Guest (Oct 10, 2011)

Yes it is. I will be setting it up with force air and not using the noisy fan. I have a newly designed fan and an old aluminum fan. In the Bus it may not make much difference. I will be using one in my boat too. We have in the plans to convert our 64 Correct Craft Ski boat to electric. Mostly for fun and to see how well it will do with the stock transmission and prop.


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