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what's the next step?

6825 Views 34 Replies 11 Participants Last post by  E4mula
It seems like the style of traction motors available haven't changed much over the past 10 years. I can't imagine there's not a new design coming down the line. What is the next big change in design, anybody know? In my opinion the weight has to be the biggest hurdle to overcome. DC motors weigh too much in my mind. The question is can they be re-engineered with lighter components that maintain the same energy as the current components?
I see this same problem in current auto engines. The tech is there to produce lighter assemblies yet they haven't had a good enough reason to force their hand into using it yet. Oil is still too easy to get so the extra weight of the vehicle can be overcome by more power but at an expense of efficiency.

Does the traction motor industry need a large sum of money to get things started? Is there any pressure being put on them yet? Maybe there is a lot more going on than what we see from our view. Do you suppose the traction motor companies already have a good head start but their not showing their hand just yet? I've read on here about companies that have a product but they don't sell to individuals, which seems counter productive to me.
Anyway I'm just thinking through my fingers. It sure would be nice to know what's around the corner.
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Discussion Starter · #3 ·
That was my point precisely. Auto engines weigh so much because it's cheaper to just make more hp to achieve performance goals than to use new tech and tooling to lighten them. Plus most IC engines are reciprocating machines and require much heavier construction than rotating machines so some of that weight is needed.
As my screen name implies I'm a 2 stroke gearhead. So when I'm comparing my style of engine to any other style, my beloved 2 strokes produce more hp per lb of engine weight than anything else. In my world a racing engine that lasts all season without failure can produce 1.5 to 2.0 hp/lb naturally aspirated and 4.0 hp/lb when forced induction is used. Auto engines don't really compare to these numbers and from my research neither do DC motors. I think they will some day and yes the money is well spent in the battery development world.
Just for comparison sake, how much horsepower does a off the shelf 100 lb DC motor produce (60 min. rating)?
 

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Discussion Starter · #6 ·
When I worked for Arctic Cat the dyno operators that tested durability would make 60 minute runs at full throttle at peak hp rpm. If all goes well they just have to keep feeding the fuel tanks.
The snowmobile world uses 180 hp 2 stroke engines that weigh in near 90 lbs and they can run for at least 60 min on 91 oct pump gas. This is the stock engine configuration. Now the modified versions with turbo charging (not OEM) can produce 480 hp in the same 90 lb package (+turbo wt) and that is good for drag racing and speed runs, but when tuned properly will last a season of racing.

This is my dilemma. I'm soo use to light weight engines and fuel cells that it's very hard for me to build an apples to apples performance vehicle. You guys talk about 500 lbs of motor and batteries like it's normal. A 400 hp race snowmobile only weighs 500 lbs total.
I guess if I were a car guy then it would compare favorably for the electric conversion, but I'm not and this is frustrating for me. I want to build something electric in the worst way, and on a customers dime not mine :D, but I can't seem to find the right project for the available parts. Roadrace vehicles are as good as any place to start with because they don't have crazy hp so it's a better match for EV. I'm more into terrain racing were weight is a huge penalty, and I like drag racing were hp rules the roost.
 

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Discussion Starter · #9 ·
good info guys, and I tend to believe the time spent on wheel motors is kind of useless myself. There are so many variables that don't lend themselves well to wheel motors for production vehicles. The only wheel motor driven vehicles that make sense to me are mining trucks.;)
Major, I can imagine the EV1 motor your using has got to be a pretty nice quality piece. I agree with you that AC or some variation of it is likely going to be my style of motor to meet weight demands.
I think part of my problem is trying to grasp what is maxed out and what is not. With ICEngines there's always something you can add or inject or modify to take it another step. I think I was hoping there were those same types of stage tuning/building one could do with a traction motor, AC and DC. It appears the structure of them is well built and doesn't allow for much altering for better performance, yet anyway.
I hope to have my dyno built by end of winter and maybe that will be my best test time. If all goes well then putting it to use in a drag sled or ATV would be my next step.
Todd, I've come to realize the good hp comes from high voltage and monster packs, which don't work too well on a snowmobile, better than a motorcycle but still only so much room to work with. The nice thing with sleds is the width where the motor sits, it's around 34", so 2 motors end for end is doable.
I just have lots of possible scenarios and can't seem to chose just one.
And yes we don't need much low rpm torque in a light weight vehicle because we will just spin off the line anyway, plus we use CVT so a nice power peak is what's needed. We really can't get much quicker than we already are. If you look at Zombie's timeslips you can see his 60' times of 1.6's , we are in the 1.2's and on the well prepped tracks 1.1's, yes that means that after 1 second or so we would be so far ahead of zombie he wouldn't believe he's getting whopped by an overgrown weed eater built like a tank. The usual response to seeing a sled run 160+ mph in the 1/4 mile is "what the he-- was that".
 

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Discussion Starter · #13 ·
The Zombie weighs over 2300 lbs also, I believe. How would the sleds look lined up with the Killacycle... a little more comparable weight? I think it's 60mph times are under 1 second... not sure about 60 ft.
Actually very close to the sleds that actually use sled engines to start with. The outlaw sleds with dual engines and such can't compete at NHRA or IHRA tracks because of safety rules, but the more normal (safer) sleds are in that same area of 7.80's and 170ish mph, I think the record is 7.70's @180ish right now. The sleds also weigh about the same as the killacycle.
The biggest difference is the big heavy track and not tires. The snowmobiles that I speak of are over 500 hp at the crankshaft but they lose so much hp turning a track that they suffer speed as well as not as good traction off the line compared to tires. When you put snowmobiles on an ice track where they belong only a top fuel bike can compare to the acceleration of an open mod sled with picks in the ice.
 

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Discussion Starter · #25 ·
When the Zombie had a Kostov it was lead acid. With its Kokam pack it is now higher -- Wayland estimates 900+ hp! http://www.plasmaboyracing.com/blog/?p=170 . So Zombie wins in hp, but I think Killacycle still has better power/weight.
The way I read it he stated the pack is capable of 900+ hp. His motor surely doesn't put out that kind of power because if it did he'd be a lot faster than he is. 900 hp range is what a few of my friends have in their cars and they run waaaaayy faster than WZ. 900 hp in that light of a car is 1.2's 60' and mid 5's in the 1/8 @ 120's mph without even trying. My friends car runs 4.9's in the 1/8 with 950 hp.
Anyway the WZ article also says he predicts using half that pack power will net him 10 second times, so I would say he's got around 500 hp like killacycle does.
 

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Discussion Starter · #34 ·
You don't have to figure it out if your controller can sample rpm quick enough to plot it against time and not let the rpm increase faster than a predetermined rate which takes a few passes to set a base line. We can do this with ICE using the ignition to limit power off the line to control wheel/track spin. The rules against traction control are for active systems such as this and NHRA doesn't allow it so be careful. I believe using this acceleration limiter approach is the best way to do it but is the most looked at by NHRA as well.
I would think this would be very easy to do with an electric motor seeing it's so easy to do with ICE.
 
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