Tomberlin chassis pmac

10kw continuous ME3031 pmac motor
14s SDI nema battery
12:1 gears 18.5 tires
Spinning 7,000 rpm and over 30mph

This is much better (faster) than reported previously
Time to get on the pmac wagon

Put normal tires on a 2005 classic:

Or a 8:1 Gen2:

6:1 sitting at Gabe’s:


Learned a lot since helping Troy with early testing.
S4 is on the light side for a 50 peak hp motor.
Tripped on over current 20-25mph, adjusted the midrange torque map to keep it under control.
At 54 volts motor draws 340a accelerating. No jk bms trips yet.
I don’t know how fast magnets can spin mechanically, but thing over 8000 rpm is possible electrically when near 72v.
Motor has not overheated during short test passes.

If anyone is sitting on a pmac motor, time to come out and play while I’m tuning.

These motors a short and light weight. Troy shoehorned one in a 2002. (Year?)

I have one - sitting waiting to go back to you at the moment. :slight_smile:
Maybe that will change

I recommend you find something to put it on. These run much nicer than I recall.
A learning curve that I needed to pass again. Well worth the effort.


So how do the torque curves look for that pmac?

Specifically regarding the em1400… you think a 17 to 12 gear change and then stuffing a monster PMAC in there is dooable? And minimal loss to the loaded capacity / performance - as you know, eM’s work for a living…

I have 12:1 and 18.5" tall tires. Runs over 30mph easily.
So bigger tires:


This is continuous torque.
Set in dvt to 660lb/in 75 nm 55lb/ft peak.
90% efficient 1/2 the weight of 3 phase motor.

Have you tried the S6 + Pmac I’ve sent you? they were matching in a 72v car.

I always thought 5k rpm max on Pmac but if it’s 7k then everything changes


As you know, weight don’t mean shyt to an eM with their steel frames, but the efficiency and torque curve are nuts…

Do you have dimensional schematics on that puppy? Think we can cram it into Emmy?


Oh no…
I have one here too…

I think it loses efficiency, plus motenergy does not test the glue over 5000rpm.
Runs for me. Didn’t need the size 6 but i can dump that program in the s4 for testing.
Or maybe put the s6 in my Zone hotrod. Have the 3031 pmac in it now. One of the s6 was no good, but im sure one of them is ok.
Which reminds me, i could not clear faults on a new s4 80v controller. 203 suffix
It may be something with pmac dld, cant believe a new on is bad.
Unless,… this was the one i put polaris on-road dld in.
It may mess them up.

So Bissen Performance West has one in inventory?
Dammit Janet.
Requesting a product hold…

Need to run some numbers and probably find a replacement gearbox with a different ratio but l’ll try to call later this week when I get a few moments.

5000 was from Troy, his sevcon tech, and backed up by John at Motenergy.
And that limit was at 72v. I’m down to 50v and still spinning up.
Before charging i need to test my low voltage cutback mapping.
I want full power to 3.5v then taper to zero.
If car dies too quickly limping, raise them a litle.
Sevcon defaults to a 5v ramp. I think 3v is enough for sdi cells.
This is so much fun testing, hoplng for an open schedule the rest of the week.

Eerrrrr… I might have one in my collection too… If I could only remember what my plan was for it! Maybe in a 6 seater :thinking:

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I missed this part.

I can send you another s6 if you want, I’ve had problems with one that didn’t want to communicate and then I solved it but I don’t remember what I did.

Anyways, these were mating with the motors and cars were running at 50mph (probably with the 8.9 gearbox) at 72v so it should be straight forward. (But we know sevcon is never straight forward)
Pulling dcf from it and loading in in an s4 might or might not work depending on the dld

I have one of those as well. Lots of other S6 in inventory.

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