# Warp 11 HP, Is it enough motor?



## dimitri (May 16, 2008)

Adam,

while I think that Warp11 will do the job just fine, I doubt that 120Ah cells will handle it.

Also, don't use 3.6V per cell to calc power, the moment you start drawing 3C from them the voltage will be around 3.0V when fully charged, down to 2.0-2.5 at the end of the discharge. So you better use 3.0V when figuring power levels.

Since you don't want to exceed 3C on regular basis, you should seriously consider 180Ah cells for your project.

For comparison, I have 40 cells of 160Ah ( 128V nominal ) and I can go 80mph easily with room to spare with Warp9. So with Warp11 and 45 cells of 180Ah I have no doubt you can go 100mph in Vette.

Obviously I am assuming you keep the transmission, right?

Hope this helps.


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## major (Apr 4, 2008)

adamj12b said:


> What I could figure, And please correct me if I'm wrong, is the spec sheet says the motor produces 43HP at 72V and 453A. So that would be 32,616 W. The battery pack we are using will be 162V charged so figuring with no sag at the same amperage, ( 162V x 453A ) the motor should be outputting 73,386 W. Thats 2.25 times the output power or 96.75 HP. Is this correct? That should be continuous output power correct? Do you think this is enough power to make the car do what we want?


Hi Adam,

I see dimitri has chimed in with some experience and addressed the likelihood of 100 mph and battery sag issues.

About your motor ratings. From what I can see, there is no published tested rating for this motor. I seriously doubt the power or current ratings you state are anywhere near the actual continuous or one hour capability of the motor. I suspect that the one hour rating would be below 300 amps.

Another thing. You say that it produces 43 hp at 72V and 453A. 72V times 453A = 32616 Watts. That would be input power. 43 hp = 32061 Watts for output power. That would be 98.3 percent efficient. Not likely. So in reality, to get 43 hp out of this motor with a 72 volt battery, the current will have to be substantially higher (when considering sag). No way will 43 hp be a one hour rating of this motor with a 72 volt battery in the real world.

Regards,

major


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## dimitri (May 16, 2008)

Also consider that max power is only needed for few seconds to accelerate, then cruising power is much less, although at 100mph cruising current will probably be just around 1 hour rate motor current, but considering 2C-3C battery draw you won't be driving for more than 20-30 min , so it still works out


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## adamj12b (May 4, 2009)

Hi guys, This car is going to be a street-rod/drag car. An expensive toy if you will. Range isn't the a big deal, just fun to drive. Just like a Vette should be. 

The numbers I got were from a table linked from the Netgain website: 

http://www.go-ev.com/images/003_20_WarP_11_SpreadSheet.jpg

Thats a good point to calculate power with sag of 3.0V. I did not think about that. It works out to be about 80HP even. Also, The 120Ah cells will be the minimum, Hopefully the budget will allow for the extra $3k for the 180Ah cells. I can easily fit them in the space behind the seats in the car without modifying anything and still come in under stock weight of 3153 lbs with the rest of weight mods. 

-Adam


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