# What's your EV performance?



## ElectriCar (Jun 15, 2008)

I've got a 4200lb S10 using a 144V system. It's an 9" Advance motor coupled to a rebuilt T5 NWC. Being so, I'm afraid to hammer it for fear of damaging the T5. As I understand it, the T5 is a utility transmission and not built for performance thus is limited in torque capability.

I would love to know though what the non world class is rated at and my motor as well. I have on occasion mashed it pretty well but not floored it but once. It pulled 458 amps yesterday starting in 2nd gear.

Answering your Q, it will get to 30 in first in about 3-4 seconds I'd guess before I have to change gears. It takes much longer in 2nd from a dead stop. On a final note, I've hit 75mph in 4th gear and still had more to go! And that was after driving it about 6 miles!!!


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## Bowser330 (Jun 15, 2008)

I wonder if your truck was loaded with lithium instead so it was 50% of the weight, if the acceleration would be 50% as well? Or do you think obtaining traction with all the torque gets in the way of that?? Maybe an LSD could help...

0-60 in 3-4 seconds would be nice


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## Tesseract (Sep 27, 2008)

ElectriCar said:


> ... It pulled 458 amps yesterday starting in 2nd gear....



Very important: is this motor amps or battery amps? If it's motor amps you can figure out the actual torque delivered by the motor; if it's battery amps you can only see how much you are abusing your batteries (assuming their 1C rate is lower than 458Ahr, that is  )


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## ElectriCar (Jun 15, 2008)

Tesseract said:


> Very important: is this motor amps or battery amps? If it's motor amps you can figure out the actual torque delivered by the motor; if it's battery amps you can only see how much you are abusing your batteries (assuming their 1C rate is lower than 458Ahr, that is  )


Motor amps. Dont' have a battery amp meter. 

Today btw, I thought I'd see just what I've got. Temps in the 40's so battery not at peak performance. Anyway I hammered it from a stop and *0-30 was 5 seconds in 1st gear.*


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## Camaro (Jul 29, 2008)

ElectriCar said:


> Answering your Q, it will get to 30 in first in about 3-4 seconds I'd guess before I have to change gears.


Questions. Why do you have to change gears at 30? Is it because your rpms are around 5000? If you left it in first, couldn't you get upto 45mph or so?
The reason I ask is because I'm planning on only having one gear for my conversion.


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## Voltswagen (Nov 13, 2008)

Camaro
RPM's and speed are determned by many things.
What is the ratio of the gears in your trans? What is your differential ratio? What are the size of your tires? Taller gears equals lower RPM's at higher speeds.
If you are planning to build an EV which will only use one gear on a manual transmission you could use say 3rd gear which on most transmissions would get you easily to 45 or 50mph. But the vehicle will be very sluggish off the line. 2nd gear might be better but higher RPM's at 45 or 50mph than 3rd gear.
Take any ICE vehicle...put it in 3rd gear and try to move from a complete stop. The engine will "Lug" until it gets up to a happy speed.


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## ElectriCar (Jun 15, 2008)

Camaro said:


> Questions. Why do you have to change gears at 30? Is it because your rpms are around 5000? If you left it in first, couldn't you get upto 45mph or so?
> The reason I ask is because I'm planning on only having one gear for my conversion.


It's a calculated maximum. As Volks said it's based on the motor rpm rating, trans gearing and rear. My rear is a 3.42, common in S10's. Don't recall the trans gear sizes but I have it written down. 

My maximums are 1st around 30, 2nd about 50, 3rd about 85. 

I'd advise you not stick with one gear unless you're going with a lithium pack and only want short range at that. My pack weighs about 1700 lbs with the steel racks. 

Due to voltage sag (not a problem with lithium) and hills in my area, starting off in 2nd up a hill is *very* sluggish and draws over 400A for several seconds. In first it's much quicker and pulls a lot less amperage. On the longer in-town roads or the interstate (two pass by my city) I have to hit 3rd to keep from getting killed. 

I've found with my motor when you need torque run the motor in a higher gear and for efficiency run in a lower gear. HOWEVER you can't run it slow very long or it will overheat. 

My next build will be AC with NO trans. There is a 2:1 reducer available which will allow for weight reduction and NO CHANGING GEARS since EV ac motors usually have about double the rpm range of most DC motors!


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## Camaro (Jul 29, 2008)

ElectriCar said:


> It's a calculated maximum. As Volks said it's based on the motor rpm rating, trans gearing and rear. My rear is a 3.42, common in S10's. Don't recall the trans gear sizes but I have it written down.
> 
> My maximums are 1st around 30, 2nd about 50, 3rd about 85.


When you say it's a calculated maximum, are you trying to run your motor at 2500rpm?

Thanks for the advice. I understand where you are comming from, but I'm not looking to go faster than around 55mph. Here are my calculations

I should get:
55.9MPH = (5000rpm*pi*25in/6.66)*60*1/5280*1/12

I realize that running the motor at 5000rpm is not great, but I'll only be driving that fast around 10% of the time, during a 5 -10min commute. 
I'll be driving around 30 mph 80% of the time which is only 2700rpm

The other 10% will be a low 5-10mph speeds, and I'll probably add forced air cooling to the motor.

My setup will be like driving yours in 1\2 gear all the time, and I'm hoping to keep the weight down around 3400-3700lbs.


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## Voltswagen (Nov 13, 2008)

Camaro
Will you be using a standard manual transmission?


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## ElectriCar (Jun 15, 2008)

5500rpm max. The motor is very efficient at that speed though I try to keep it at around 4500 to limit the stress on the trans bearings.


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## Zemmo (Sep 13, 2007)

To steer the thread back onto its topic, I had my EV tested for its zero to ? MPH. I have that info posted on my website. I will be redoing that when it warms up some. I have done several different changes to the car since then and would like to see how it has changed. Here is a direct link to that info on my website.

http://www.electricformula.com/Performance.html


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## Voltswagen (Nov 13, 2008)

Zemmo
Those are the most detailed driving logs I have ever seen. What is EVDash? Are you using the Link 10?
Good job!

Roy


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## Zemmo (Sep 13, 2007)

Yes I used the data output from the E-Meter (Link 10) and capture the data using a Palm IIIc and the program EVDash. EVDash was written by a guy called Ohler. I forget his first name. Here is his website:

http://www.ohler.com/palm/EVDash.html

It displays the main info you want to know about all at once, plus it has a lot of other featues like logging the usage data and you can export that out into anything you want to analize the drive even further. It is pretty cool program and is actually very usefull. I now have the palm mounted on my dash and its next to my tach and speedo.


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## POP-evolt (Aug 16, 2010)

ElectriCar said:


> I've got a 4200lb S10 using a 144V system. It's an 9" Advance motor coupled to a rebuilt T5 NWC. Being so, I'm afraid to hammer it for fear of damaging the T5. As I understand it, the T5 is a utility transmission and not built for performance thus is limited in torque capability.
> 
> I would love to know though what the non world class is rated at and my motor as well. I have on occasion mashed it pretty well but not floored it but once. It pulled 458 amps yesterday starting in 2nd gear.
> 
> Answering your Q, it will get to 30 in first in about 3-4 seconds I'd guess before I have to change gears. It takes much longer in 2nd from a dead stop. On a final note, I've hit 75mph in 4th gear and still had more to go! And that was after driving it about 6 miles!!!


Good, I am glad to hear that someone see's the same current as I do when starting in 2nd gear, my I meter only reads max 400a but it pegs out when starting .. think we have the same system..


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## POP-evolt (Aug 16, 2010)

anyone configured a tach for these monsters?? sure would be nice?? trying to figure out all the ratios for this S-10 (was a V-6 5sp tahoe), 

looks like we are all seeing about the same performance....


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## DIYguy (Sep 18, 2008)

Mine is a B4000 extended cab with about the same curb weight. I think my speeds are similar as what you mention...except maybe not 85 in 3rd...mine is a 5 speed. I have a Soliton and 192 volts of AGM batteries...so it will go pretty fast...even with all that weight. I limit the voltage to the motor to 160 volts. It has posi-track and 1600 lbs of lead. I did floor it once with the controller set to 1000 amps. (motor) It spun the tires a bit on dry pavement and lurched fwd so fast it scared the crap out of me...lol. The acceleration in 3rd gear is quite impressive actually....when the pack is fresh. I've had it over 100 mph and it was still building. I'll have to snap some times...



ElectriCar said:


> My maximums are 1st around 30, 2nd about 50, 3rd about 85.
> 
> I'd advise you not stick with one gear unless you're going with a lithium pack and only want short range at that. My pack weighs about 1700 lbs with the steel racks.
> 
> ...


Did you add a blower to your motor to help with cooling? I have one, but I do notice the heat at lower rpm also. On hot summer days, I will use a lower gear.


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