# Want to replace 17KW DC Eng by AC



## biscayne (May 15, 2009)

Hi, 
My 17KW 96V brushed DC Engine of my VW Golf2 Citystromer sounds like it would need new bearings soon. Rather than to have it rebuilt, I`m thinking to replace it by an AC Engine, since it`s more efficient. 
Can anyone recomend a reasonable priced good solution for engine and controller, or should I leave everything the way it is?


----------



## JRP3 (Mar 7, 2008)

The only reasonable choice that I'm aware of is the HPEVS series of AC motors, AC30, 31, and 50, with Curtis 1238 120V controller.
http://www.hpevs.com/
http://www.evparts.com/products/str...8-to-96-volt-street-vehicle-motors/mt5610.htm
http://www.grassrootsev.com/motorsac.htm


----------



## TX_Dj (Jul 25, 2008)

Just for clarifications, engines are mechanical devices that change heat and/or chemical reaction into mechanical force. Motors are electrical devices that change electricity into mechanical force.

You said "AC" and "reasonable price" in the same post, and this creates such a paradox that the universe is likely to implode as a result.

In my opinion, the efficiency gain must seriously be contemplated for the incredible increase in costs to achieve it.


----------



## JRP3 (Mar 7, 2008)

TX_Dj said:


> You said "AC" and "reasonable price" in the same post, and this creates such a paradox that the universe is likely to implode as a result.
> 
> In my opinion, the efficiency gain must seriously be contemplated for the incredible increase in costs to achieve it.


A Warp9 + a Curtis = about $3400 
AC50 +AC Curtis = about $4300
However the AC Curtis includes a tach, voltmeter, ammeter, motor temp monitor, controller temp monitor, and fault code display from the controller. If you added all that to the Warp9 system the total difference would be less. Then factor in the lack of brush maintenance, and no possibility of brushes overheating and failing, and the joys of regen, and the price difference looks even smaller.


----------



## RoughRider (Aug 14, 2008)

JRP3 said:


> A Warp9 + a Curtis = about $3400
> AC50 +AC Curtis = about $4300
> However the AC Curtis includes a tach, voltmeter, ammeter, motor temp monitor, controller temp monitor, and fault code display from the controller. If you added all that to the Warp9 system the total difference would be less. Then factor in the lack of brush maintenance, and no possibility of brushes overheating and failing, and the joys of regen, and the price difference looks even smaller.


so what you say on the newest regen test of jack??

the result is, that regen gives you ZERO extra range...


----------



## JRP3 (Mar 7, 2008)

It gives Jack zero range, and maybe others with similar driving patterns. He was driving mostly flat to moderate hills and there was very little stopping. If your driving is similar you'll probably get similar results. When I'm going down a mile long hill using an average of 50 amps back into the pack to hold my speed, instead of brakes, I'd be surprised if that doesn't translate into some range increase. I'll be doing my own testing to see what happens.
Increased range is only one of the possible benefits of regen for me. I really like controlling my speed almost entirely with the accelerator pedal, and I'll still get less wear on the brake pads, less brake dust on the wheels, no brush dust or replacement, and I might have shorter stopping distances in emergencies since as soon as I lift off the throttle regen begins to slow me down. I can also do all of my driving in second gear since I can run at 6500RPM all day and not worry about the motor flying apart, and the higher RPM's keeps the fan moving faster. The added safety factor of a controller failure not causing a full on runaway is a nice feature as well.


----------



## RE Farmer (Aug 8, 2009)

JRP3 said:


> Increased range is only one of the possible benefits of regen for me. I really like controlling my speed almost entirely with the accelerator pedal, and I'll still get less wear on the brake pads, less brake dust on the wheels...


Agreed - Better braking without having to upgrade brakes is my primary reason for regen, as well as no runaway using AC vs. DC, i.e. safer. Getting back some energy is just a bonus, and really only applies if your drive profile has lots of start & stop. I was surprised that Jack's results indicated possible loss of efficiency due to regen - curious. Unfortunately, my honey-do list has back-burnered my MG conversion, plus it needs some plain old restoration, so I won't be running my own test for quite a while.

I'm hoping the AC will be more efficient - Jack mentioned at the beginning of this week's show that his speedster-Sr. was using more energy than Part Duh, but Sr. may have had a problem.


----------



## Guest (Jul 13, 2010)

I'd say remove the motor and pull it apart and replace the bearings and brushes at the same time and clean it out yourself. It is really not that hard to do. I volt for you to keep your DC and maybe do a voltage upgrade instead. A good set of performance disk brakes and you will be good to go and if you get lithium you will be doing even better. Better to run through a few sets of disk pads and maybe a rotor or two vs spending an few thousand or more for AC and regen for saving your brakes. Just be sure your brake system is better than stock. 

Pete


----------

