General upgrade Qs on 08 TXT PDS cart

[g.schucks]

Good afternoon everyone, and first off, thanks in advance for the help. Two main areas of questions is for lifting the cart and making more torque. More torque is needed for the big hill at the lake to get to and from the dock already with the cart stock. It will make the hill, but it is not happy about it.

36 volt cart, new batteries last year. Have replaced the 5 cables in the battery pack with good 4G wire, plan on doing the other 5 very soon.

Looking at a lift to clear this tire... Carlisle Stryker 22x11-8. I have access to three free or very cheap brand new tires of this brand and model. Buy one more for ~$80 and I have a good start to lifting the cart.

1. Will a six inch lift clear this tire/wheel combo?
2. Will I be OK with the stock 8" wheels? If not, can I run wheel spacers to get by? If so, how big of a spacer is needed?
3. Will I lose torque going with the bigger tire? If so, would doing the bigger solenoid and alltrax 400 like Scotty and others sell be enough to make that back up?

I have a good opportunity to get these tires, so I would like to be able to make it work if I can.

Tires - http://www.walmart.com/ip/Carlisle-S...-Tire/23597400
Lift - http://www.ebay.com/itm/121311523547...S:1123&vxp=mtr

Thanks, hopefully I didn't leave anything out.
g.schucks

[radioman]

When you get through modifying it with bigger tires you will be sorry you did. Be prepared to spend some money if you want it to climb hills better. Upgrade with new motor, controller, solenoid, etc. ScottyB can help you with needed upgrade parts.

[JohnnieB]

Question #3 - You will loose at least 23% of your torque going from an 18" tire height to a 22" tire height.

In addition, that is a very low pressure tire (5 PSI max inflation pressure), so it may very likely be an amp hog, loosing a lot more torque than the simple change in final drive ratio indicates.
http://www.carlisletransportationpro...sports/Tires33

To run those tires, you'll probably need to upgrade to 48V and a 500A controller plus suitable solenoid and cables in addition to a high torque aftermarket motor.

You can find 23" tires with aggressive treads that have an inflation pressure in the 20 PSI range, but you still loose the about 23% of the torque due to the change in the final drive ratio. Stick with tires under about 20" and you probably won't have to lift cart.

[g.schucks]

Wow, this is why I ask the experts! Thank you for the replies. I think I just scratched the lift idea all together! guess I will just finish out the cables and think about the alltrax 400 and solenoid upgrades for now just to tackle that hill a bit easier.

g.schucks

[scottyb]

Originally Posted by g.schucks

Wow, this is why I ask the experts! Thank you for the replies. I think I just scratched the lift idea all together! guess I will just finish out the cables and think about the alltrax 400 and solenoid upgrades for now just to tackle that hill a bit easier.

g.schucks

You are correct. The last thing the cart needs to face the hill climb is bigger tires which equal taller gear ratio. If you go with 20" Scorpion knobby tires, you can put your lift kit money towards a 400a Alltrax pkg like #808. This will allow the motor to access 30% more amperage which it will use to produce an equal amount of torque. And allow top speed of 24mph on stock tires.
Another benefit of running the upgraded control and solenoid is the option to run a 7th battery in this cart for 42v operation. This will produce an additional 17% more speed and torque.

[g.schucks]

Do you think I would break even with upgrading to the Alltrax 400, 4G cables and bigger solenoid with this lift and tire? I hate to pass on these three tires that are essentially free. If it will just flat out not work, it is what it is. Just sucks to have these free tires and not be able to use them.

g.schucks

[JohnnieB]

With those tires a 400A controller, 4Ga cables, a compatible solenoid and a stock PDS motor, I have serious doubts if your cart will be able to climb the hill it now climbs, but is not happy about doing it.

To put it into a different perspective, I have roughly 113% more torque than a stock PDS and to run those tires, I'd up my battery pack from 42V to 48V and switch to an ES-63-49 motor, which would up my torque by 17% and 10% respectively for a total of 140% above stock and my cart would still probably slow to walking speed on hills that it will now accelerates on.

Those are special purpose tires designed for driving through swamps and to run them you'll have to upgrade your cart far, far, far more than what you've mentioned. The tires may be free, but the needed upgrades won't be and the end results may not be suitable for the terrain you have.

[g.schucks]

JonnieB that really puts it into perspective for me, thank you. So I think I am just going to totally ditch the lift for now and focus on more torque. I think I am going to go with an alltrax 400 and bigger solenoid. The thought is that if I start there, I could still go to the 42V option if I still wanted more power/torque.

Questions to doing this would be how does this effect the stock motor and the batteries? Any harm pushing that much more voltage to the stock motor? Will this shorten the life of the batteries that I just replaced brand new last year? I felt good about the price I paid for them, but 600 bucks is 600 bucks and I don't look forward to replacing them all. With the thought of going to 42 volt, would it be better to do this now since the batteries only have one season on them so far?

I want to get setup for this year at the lake to be confident that this cart will climb the hill from the dock with the cart loaded with people and coolers. It will make the hill now, but very slow and seems questionable at best.

Thanks,
g.schucks

[JohnnieB]

The trick is to figure out what you want the cart to do, or to be, and then build towards that goal.
What makes it tricky is that just about everything you can do to an electric cart is a juggling act.
IE: If you install taller tires, you gain speed and loose torque. If you install shorter tires, you gain torque and lose speed.
If you install a Hi-Speed motor, you gain top end speed and loose low end torque while installing a Hi-Torque motor gains low end torque and looses top end speed. (However, there are motors that will increase both torque and speed)

On the other hand, if you install low pressure tires you loose both torque and speed, but gain traction in swamps and deep sand.
Conversely, if you increase the pack voltage, you gain both torque and speed, but have to get a charge that matches the pack voltage. (Solenoid coil also has to match pack voltage, but there are solenoids that will work at 36V, 42V and 48V.)

Then there is the beauty is in the eye of the beholder aspect. Some people like the looks of carts you need a ladder to climb onto, while other likes them slung low to the ground. Either is okay if that is the look you want, or the ground clearance needed, but you have to make appropriate compensations to offset the torque or speed and/or stability losses caused by the "Look" or it is all show and no go.

Okay, Ill get off the stump.

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A stock PDS motor can only handle short bursts (<1 Minute) of 400A at 48V, but due to the laws of physics, on stock height tires (18") and stock (12.44:1) differential gears, the only time a stock PDS motor is capable of drawing 400A@48V is at walking speeds (<1,000 RPM or 4 MPH) and below.

A stock PDS controller is 300A, so installing a 400A controller will give you about 33% more low end torque and will climb the incline coming up from the dock better, but will still slow down quite a bit. (All electric carts slow down going uphill.)

Going to 42V will increase the torque by nearly 17% across the board, so it will climb up from the dock quicker and have more top speed on level ground.

My original setup was a DCX400 and a 48V 400A contentious/1000A Peak solenoid with 2Ga cable throughout, fed by a 36V battery pack. The top speed was 24 MPH and it would climb 20° inclines at better than walking speeds.

My goal was range rather than speed or torque and I wasn't getting the range I wanted, so I replaced the 36V-225AH (8.6kWh storage) battery pack with a 42V-245AH (10.9kWh storage) pack. That gave me the round trip distance I wanted plus some wiggle room and it upped the top speed to 28MPH and didn't slow as much on the steep hills.

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Ideally, if you want to go to 42V by adding one battery to you existing 36V pack, it would be best to find a used battery the same make and model and about the same age as the existing batteries. Adding a new battery (same make and model) will work, but the new battery will quickly age to the same age as the existing ones and the overall life of the pack might be a little less than what it would have otherwise been, but you'll be getting improved performance for the slightly shorter lifespan.

[g.schucks]

Originally Posted by JohnnieB

A stock PDS motor can only handle short bursts (<1 Minute) of 400A at 48V, but due to the laws of physics, on stock height tires (18") and stock (12.44:1) differential gears, the only time a stock PDS motor is capable of drawing 400A@48V is at walking speeds (<1,000 RPM or 4 MPH) and below.

A stock PDS controller is 300A, so installing a 400A controller will give you about 33% more low end torque and will climb the incline coming up from the dock better, but will still slow down quite a bit. (All electric carts slow down going uphill.)

Going to 42V will increase the torque by nearly 17% across the board, so it will climb up from the dock quicker and have more top speed on level ground.

Question about the limitation of the stock motor you listed there. When drawing that at walking speeds are you saying walking speed like trying to go up a hill that slows down the cart to that speed?

You might have talked me into the 42V addition as well. Just wish I didn't have to replace the charger as well, they are not cheap!

Any ideal knobby tires that would keep the stock 18" size that you could recommend? Had the cart out in the woods earlier today and I could have used something better than the turf tires I have now.

g.schucks