Hunting Buggy Build. Help appreciated!!!
 

I have a 2002 Ezgo TXT.
My cart is bone stock with the exception of a camo body and 10" chrome wheels and rear seats. I have just purchased 8 6volt Trojan T105's to convert it from 36 to 48v as i have read that Trojan battery company itself has put out an estimated range for various configurations. And they estimate that 8 6volt T105's will get you an estimated 80 percent longer drive time than the 6 8volt T875 configuration ( from an estimated 20ish miles to 35ish miles ). So i opted for more juice!! I also have the SR48600 Alltracks controller, HD solenoid, 6" axle drop lift and 23" Maxxis Bighorn knock offs that are 7" wide. I figured a more narrow wheel would be less rolling resistance thereby reducing battery consumption. This is my first build and all my research has lead me to leaving the stock Black motor in until i have to upgrade. I was informed that the "gray" motor didn't really change performance very much with the 48volt conversion, however the "black" motor came to life so to speak after the same upgrade, so thats what I went with for now..
Any advice from anyone who has done this will be greatly appreciated. I am using the bag-well space for the additional 2 batteries. I also have all 2ga wires for the build. anyone that has already done this, please chime in with any performance or range benefits. Thanks in advance.

Re: Hunting Buggy Build. Help appreciated!!!
 

I can't speak on behalf of the range increase, but I did upgrade my 2000 EZGO TXT from 36v to 48v. I put in 6 of the T875's, new solenoid, Alltrax 400 Amp XCT, 6" lift kit and 23" wheels. 73124-g08 2.5 HP 36VDC stock motor in the cart. Upgrade process and and performance improvement here on YouTube. Let me know if you have questions!

Re: Hunting Buggy Build. Help appreciated!!!
 

Please post a like to this information.

Range is determined by battery storage capacity vs the cart's Watts/Mile, much akin to how a car's driving range is determined by how many gallons the fuel tank holds vs the car's MPG. There is one difference though, the slower you draw energy from a lead-acid battery, the more energy can be withdrawn (Peukert's law).

A 6X8V pack of T-875 batteries stores 8.7 kWh of energy while a 8X6V pack of T-105 batteries stores 11.5 kWh of energy, or 2.8 kWh more. That is only a 32% increase in storage capacity (range). Granted the discharge rate will be slightly lower for the higher capacity pack, but I seriously doubt if the Peukert factor is enough to up the estimated range difference from 32% to 80%.

On the other hand, I manged to get a 35ish mile range from my 7X6V (42V - 245AH) battery pack (10.9 kWh of storage), but I have a sepex drive with regen braking that puts some energy back in the battery.

Re: Hunting Buggy Build. Help appreciated!!!
 

I was just going by simple math. May not be 100% correct, but it has to be in the ball park.
6 8volt T875's have 1020AH, and 8 6volt T105's have 1800AH. If you divide 1020AH by 20ish miles= 51AH per mile.

1800AH divided by the same 51AH per mile=35 miles.

going from 20 miles to 35 miles is way more than 32% increase. roughly 75% increase

Re: Hunting Buggy Build. Help appreciated!!!
 

was there a significant torque increase?

Re: Hunting Buggy Build. Help appreciated!!!
 

First, learn how to calculate the AH of a 48V battery pack. (Volts add in series, AH stay the same.)

Not quite sure where you get the 20 mile range figure for the 6x8V T-875 batteries. Have you ever ran a T-875 pack in that specific cart?

You're also assuming you can get 100% of the stored energy out of lead acid batteries without irreversibly damaging them. Trojan, and some other deep cycle battery manufactures, say you can do 80% discharges (20% SoC - State of Charge), but they sell batteries and the lower the average SoC maintained, the shorter the cradle to grave lifespan of the batteries, so most electric cart owners try not to discharge their expensive battery pack lower than 50%.

Measuring the At-Rest voltage before and after driving measured distances over mixed terrain, with different amounts of aggressiveness, my cart gets from 3.3AH/Mi to 5.6AH/Mi, the average AH/Mi being slightly higher at 42V than it was at 36V over the same course. The tests include a both stock controller and an Alltrax DCX400 running at 36V with stock PDS motor.

If you want a fairly accurate guesstimate as to how much the range difference is between a T-875 48V pack and a T-105 48V pack you at the differences in the runtime published by Trojan for their T-105 and T-875 batteries with the same discharge rate. Unfortunately, Trojan does not publish the capacity minutes for the 56A and 75A discharge rates, which is
average amp draw range for most relatively stock carts, so we have to go with the 25A rate

T-105 = 447
T-875 = 295

447 - 295 = 152
152/295 = .5152542 = 52%

IF, and that is a big if, the cart will get 20 miles with a T-875 pack, it will get (mathematically) 30.3 miles with the T-105 pack. It will be less than that due to the Amp draw averaging upwards of three times the rate that was used for comparison and the Peukert factor and peaking at ten time or more that amount.

FWIW: The increased range going from a 225AH 36V pack to a 245AH 42V pack tracked the increase in kWh stored fairly well, but the 225AH 36V pack was not the picture of health, so it may have been less.

Re: Hunting Buggy Build. Help appreciated!!!
 

I dont really understand nor comprehend all you are talking about due to the fact that i flunked out of the NASA Aeronautical Program sometime back. Im not an engineer, chemist, or battery tech specialist. I simply use common sense and good old arithmetic that Ms Shuler taught me during my second tour of third grade!!! Served me pretty well until now!!!
I do understand batteries in Series vs in parallel. As for your comment AH dont change? yes they do!! The T105 has 225 of them. 8 T105's has 1800 of them. Thats a big change!!!, And I am not assuming that I can use 100% of the stored energy. I am well aware that I shouldn't draw below 48.4 volts, so thanks for assuming that i was assuming.
Also my uneducated common sense tells me that your not really wanting to help me, but rather to try and prove me wrong on every thing i say, and im not into that. Thats not why i posted on here!!!
I have all my parts already "PURCHASED" so i dont need stats or corrections, or different thing i should have bought... I simply want to no if there is any issues i may run into installing or building the setup I have? and to anyone that has done the 8 6volt battery upgrade with bigger controller on a stock motor, I am inquiring about any performance gains? Thank you again!!!!!

Re: Hunting Buggy Build. Help appreciated!!!
 

Contrary to your apparent belief, I really do want to help you. My intent wasn't to prove you wrong, it was to dispel false information and excessive expectations for future readers of this thread.

True, a T-105 is rated at 225AH at a 20 hour discharge rate. However, when connected in series the battery voltages add and the AH remain the same, so eight t-105 batteries connected in series produces a 48V - 225AH battery pack. See attached excerpt from the Trojan User's Guide explaining series, parallel and series/parallel configurations.

As for performance a six T-875 48V battery pack weighs 378 lbs and a eight T-105 48v battery pack weighs 496 lbs, so the latter has more range, but the cart performance (acceleration and maintaining speed going uphill) is less due to having the equivalent of an additional passenger (118 lb) onboard all the time.

Re: Hunting Buggy Build. Help appreciated!!!
 

Like I said, I want someone’s advice that has done this build, not theoretical information based off numbers and I think so’s. No offense to anyone but I want information based on reality. From someone that has done this. No need to respond if you haven’t ran 8 6volt batteries in a 48volt system. I’m not interested in what may happen due to certain effect or theories, or what should happen due to whatever reason. I need real life ( because you have been there and done that ) information.

Re: Hunting Buggy Build. Help appreciated!!!
 

I just got my Alltrax SR600amp controller and 400amp solenoid with the upgraded diode and resistor. All 2ga wires everywhere. Freshly charged new 8 T105’s from a brand new 48v Accusense smart charger.

The difference in performance is AMAZING!!! It sure about the range because I am waiting on a volt meter to monitor my energy consumption so I don’t drain them below 48.4v.
But my oh my what a difference the 48v upgrade made. It will leave spin marks and hard pack gravel for 8’-10’ . Not that I will try to do that on pavement, but I bet it would carry the front tires if you wanted it too. Speed is up to 18mph from 11mph. I haven’t installed the lift or the 23” Bighorn tires yet so with everything I can read on tire comparison charts, going from 17” tires to 23” tires should give me an extra 7-9mph. So 26-28mph with a stock 2hp motor is awesome for me.
I will let everyone know the mileage when I get everything installed. I live in The Smokey Mountains in extreme mountainous conditions, this the reason for the 8 battery upgrade. With traditional 36v carts I could only get 10-15 miles on a charge. So I am realistically hoping for 20-25 miles. With my set up. I would be very pleased with that.