# 4 degrees uphill slope...



## TheSGC (Nov 15, 2007)

Now that's good stuff!

I have to drive up three of those hills every day, but at 35 MPH, and my 96 volts pack takes a beating doing it, and my last hill usually leaves me crawling up it, although I haven't tried it since my EV went over a huge upgrade and I figured out acceptable voltage sag for my batteries.


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## octagondd (Jan 27, 2010)

This is great Qer. What is the curb weight? Also, what AH LFPs are you using?


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## Qer (May 7, 2008)

octagondd said:


> This is great Qer. What is the curb weight? Also, what AH LFPs are you using?


Not me, a test car we (ok, they over at the other continent) are building. 65 160 Ah cells with 1 or 2 disconnected due to killed cell (test car, ok?). Curb weight is probably around 3479 lbs (estimated).

Oh, and it's a 2002, not 2004.


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## etischer (Jun 16, 2008)

To contribute to the uphill data:

6% grade
Maintaining 60mph
3700lbs + 200lbs driver
99 LiFePo (330v nominal)
2001 VW Passat with Ford/Siemens AC motor. 

Power consumed is 180A @ 312V.


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## Matthijs (Jun 19, 2009)

This one? 









http://freemob.files.wordpress.com/2009/12/vw_paint-002.jpg


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## Tesseract (Sep 27, 2008)

Matthijs said:


> This one?
> http://freemob.files.wordpress.com/2009/12/vw_paint-002.jpg


Yep - it started off as a hideous lemon yellow but was painted flat black at the customer's request.

FWIW, the website I use that gives a much more realistic estimation of actual power required compared to the EV specific ones is:

http://www.apexgarage.com/tech/horsepower_calc.shtml

It predicted that the aforementioned New Beetle would require 20.9hp to go 60mph on a flat road and the Soliton1 reported ~21kW, which given the average efficiency of the WarP motor being in the 75-85% range depending on current, this estimation is pretty much spot on.

The "motor power limit" function of the Soliton1 can make doing this sort of testing a lot easier. Just limit power to, say, 20kW and see how fast you can go on a flat road first in one direction then in the opposite (to cancel out the effect of wind). Then to get an object lesson in the cubic law of aerodynamics, double that power limit and see your speed go up a paltry few mph!

Unfortunately, I didn't think of doing this test with the New Beetle until after it was delivered to the customer.... next one up at Rebirth Auto is a 2002 Volvo V70 (which despite weighing some 1000lbs more has a much lower CdA, and so only requires 16.8hp to go 60mph).


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## Matthijs (Jun 19, 2009)

Pretty cool way to measure the actual power required to push the car along at a certain speed. It makes you realize how important aerodynamics actually are. 

Here is a video of the Beetle when it was delivered at Schiphol airport in Holland. It got damaged because it fell of the platform.  And because the freight forwarder did not pay up they wanted to impound the car. 





Link


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## peggus (Feb 18, 2008)

Tesseract said:


> Yep - it started off as a hideous lemon yellow but was painted flat black at the customer's request.


Hey, I resemble that remark!


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