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Been lurking and digging through posts here for a while, figured it would be a good time to say hi, smart group of peeps here!
  • Your skill level with auto mechanics and fabrication
    • (15 years turning wrenches and slinging steel)
  • The range you are hoping to get (how many miles/charge)
    • (no idea how long batteries last while trail riding, thinking around a 40 kw/h pack)
  • What level of performance you are hoping to get
    • (would like to max out the capability of the controller)
  • How much money you are willing to put into your project
    • (my battery budget is a few to 5 grand)
  • What parts you've already considered, if any.
    • (Ive got an HPEVS 35 Motor and a curtis 1239e-8521 controller)
Had my samurai for years, It's on 35's and is stripped completely down for offroading purposes. I was finally able to snag a motor and controller for ten cents on the dollar at an auction.

So now time to design and lots of stuff has changed since last time I got into EV's a bunch.

So without further ado:

Configuration:

-Too keep the trans or remove the trans and go right to the transfer case? I'm thinking keep the trans.

-Who are the new hotness providers in adaptors these days? Internal key slots are a pain to pull off for the hobby machinist, is this a part most people usually buy?

-I see some liquid cooled baseplates available for the Curtis, but I also see testimony about guys just replacing the stock heat sink on the bottom with a way beefier one and never having any temperature issues. I'm slightly concerned about heat, Not much airflow when you're slowly rock crawling.

-Is it possible to get more hrsprs out of the curtis with liquid cooling? Has anyone hacked these things and seen what they're really capable of?

-Max input voltage to the Curtis is 170 volts DC, so that's what I'm going to aim for with the batteries. What's everyone using for contactors that can handle 170 volts these days? Same with DC/DC converters

-What kinda scrap yard parts are commonly used in EV's these days? Electric Power Steering pumps? Electric Brake boosters? Electric water pumps? Electric Fans? Contactors? Any tips on year/make/model of stuff I should keep an eye out for at the pick and pull?

Controller:

I feel like an idiot but I can't even find a proper datasheet for this thing, just a basic overview. Where is a good resource to find the manual and all the little details like what connectors I'll need, and what software is required to program it and all that jazz. Curtis website just says contact curtis, so we'll see if they email me back.

Batteries:

Now this is where it gets really wild. Back in the day guys were doing group orders of cells by the pallet load from maos dollar store. Is this still a thing or have 18650s supplanted those pouch batteries everyone used to buy to build packs from.

Are there preferred EV batteries to get from scrap cars?

If I do end up building my own packs (which I'm kind of leaning towards) what is the new hotness in BMS solutions these days?

Is there a good resource for the KwH and Nominal voltages of various EV packs? I'm having difficulty finding voltages for the packs to figure out how many i need to get upto 170

Thanks for taking the time to check out my questions, appreciate the input of your experience.
-Coleston
 

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Some builders use electric pumps (from OEM electrohydraulic steering systems) to replace engine-driven pumps, but others use electric racks or columns. Electric columns are available aftermarket, and are probably easier to use than working with salvaged OEM components, but they're expensive.

For brake boost, electric vacuum pumps are annoying and some builders are now adapting Bosch iBooster electrically assisted master cylinders salvaged from various production cars; Tesla uses them, but they're not the only ones (in both EVs and engine-driven cars).

For Curtis manuals, first try a web search by model name - various retailer and enthusiast sites have copies of some manuals posted.

For battery voltage, just assume 3.2 V nominal for LiFePO4, and 3.75 V nominal (~4.2 V maximum) for other lithium variants.

Choosing battery modules depends largely on your preference regarding active thermal management (liquid cooling), configuration choices (series/parallel cell arrangements), packaging constraints (what fits), and simply what can be found. The PHEV modules were popular (from the Chevrolet Volt and the Chrysler Pacifica), but they're small (in energy capacity) and the LG Chem 16S modules (intended for the Pacifica) which some companies were selling are no longer available. Leaf modules (of any generation and capacity) are still used; they don't need cooling and the original style are easy to reconfigure. The Tesla Model S modules are still popular, and a rare few projects are now using Model 3 modules. There are lots of other choices, and no single recommendation.

It's unlikely that building your own pack from individual cells will make sense, unless you want LiFePO4, but you may need an aftermarket BMS even with OEM battery modules. LiFePO4 prismatic cells have fallen out of favour due to cost, bulk, and weight (for a given capacity)... and the annoyance of all those interconnections.
 

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I'm same boat brother! 1989 Suzuki Samurai on 33's looking at completing the conversion this winter. Lets stay in touch, Samurias should be an easy conversion and they deserve it given their lackluster 65HP that barely hits 70 floored going downhill with a tailwind...

Been lurking and digging through posts here for a while, figured it would be a good time to say hi, smart group of peeps here!
  • Your skill level with auto mechanics and fabrication
    • (15 years turning wrenches and slinging steel)
  • The range you are hoping to get (how many miles/charge)
    • (no idea how long batteries last while trail riding, thinking around a 40 kw/h pack)
  • What level of performance you are hoping to get
    • (would like to max out the capability of the controller)
  • How much money you are willing to put into your project
    • (my battery budget is a few to 5 grand)
  • What parts you've already considered, if any.
    • (Ive got an HPEVS 35 Motor and a curtis 1239e-8521 controller)
Had my samurai for years, It's on 35's and is stripped completely down for offroading purposes. I was finally able to snag a motor and controller for ten cents on the dollar at an auction.

So now time to design and lots of stuff has changed since last time I got into EV's a bunch.

So without further ado:

Configuration:

-Too keep the trans or remove the trans and go right to the transfer case? I'm thinking keep the trans.

-Who are the new hotness providers in adaptors these days? Internal key slots are a pain to pull off for the hobby machinist, is this a part most people usually buy?

-I see some liquid cooled baseplates available for the Curtis, but I also see testimony about guys just replacing the stock heat sink on the bottom with a way beefier one and never having any temperature issues. I'm slightly concerned about heat, Not much airflow when you're slowly rock crawling.

-Is it possible to get more hrsprs out of the curtis with liquid cooling? Has anyone hacked these things and seen what they're really capable of?

-Max input voltage to the Curtis is 170 volts DC, so that's what I'm going to aim for with the batteries. What's everyone using for contactors that can handle 170 volts these days? Same with DC/DC converters

-What kinda scrap yard parts are commonly used in EV's these days? Electric Power Steering pumps? Electric Brake boosters? Electric water pumps? Electric Fans? Contactors? Any tips on year/make/model of stuff I should keep an eye out for at the pick and pull?

Controller:

I feel like an idiot but I can't even find a proper datasheet for this thing, just a basic overview. Where is a good resource to find the manual and all the little details like what connectors I'll need, and what software is required to program it and all that jazz. Curtis website just says contact curtis, so we'll see if they email me back.

Batteries:

Now this is where it gets really wild. Back in the day guys were doing group orders of cells by the pallet load from maos dollar store. Is this still a thing or have 18650s supplanted those pouch batteries everyone used to buy to build packs from.

Are there preferred EV batteries to get from scrap cars?

If I do end up building my own packs (which I'm kind of leaning towards) what is the new hotness in BMS solutions these days?

Is there a good resource for the KwH and Nominal voltages of various EV packs? I'm having difficulty finding voltages for the packs to figure out how many i need to get upto 170

Thanks for taking the time to check out my questions, appreciate the input of your experience.
-Coleston
 

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I'm in. Looking forward to seeing what you come up with. 5 speed manual will allow you to have your choice of tons of ratios off road in low-range but you might consider ditching it for the weight and space saving, though I'm sure the trans in the Sami is feather light compared to most.
 

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... 5 speed manual will allow you to have your choice of tons of ratios off road in low-range but you might consider ditching it for the weight and space saving, though I'm sure the trans in the Sami is feather light compared to most.
According to a randomly selected source, the entire transmission (without clutch, flywheel, or shift linkage) weighs 71 pounds. Not a lot as transmissions go. I think the space is more of an issue.
 

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Best bet for batteries is a wrecked Leaf or maybe Bolt. Maybe even a Smart ED, Fiat 500e, or BMW i3. Maybe some packs from a Model S. Whatever is the most prevalent factory EV in your area that is 5+ years old...particularly if you can find a cheap wreck.

You probably won't need power steering or brakes. Fans and pumps are easily found for short money—it's all just 12v stuff. For contactors, just grab something off eBay. a Leaf box gives you two contactors and a precharge contactor.
 
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