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I'm Dave. I'm looking at converting a 96 Ranger that's undergoing a street legal off road race truck build. I got side tracked earlier this year when a classic that was in the family for decades was passed on to me. I've been busy doing a survivor type restoration between driving it off and on. Just after the first of the year I should be able to turn my attention to the Ranger.

The Ranger is intended as a lower HP desert toy. I took a stock V6 4.0 with a cracked head out of it. It's a 5 speed manual trans. It's a mid travel off road suspension front and rear with 33" tires. It was/is being built as a street legal Class 7100/7sx race truck. Converting it to an EV would make it more of a proof of concept rather than anything that had the range to race.

Skills and tools include race fab (welding, tube fab, CNC), restoration, power train, data acquisition, electronics and some shade tree paint and body. I guess I'm a jack of all trades, master of none (or very few) and hackneyed at some. Saving grace is I know when to say "uncle" and go to a pro when needed. As for tools I've got just about everything but a two post lift. I've also been part of the Open Hardware movement for the last 6-8 years primarily desktop CNC and 3D printers.

Current plan of attack is to immerse in the tech. We've wanted an EV for a few years now but what we can afford/justify doesn't have the range we need. We're a single car family for our daily (not counting the classic Mustang). For a daily we'd need 300 miles or so range as we go out of the area often. For the Ranger I'd like 100 mile range and the ability for a top off road speed of around 60 mph.

As for budget I'd like to keep it to no more than $10k. That's not looking so good but I'd like to hit around there. One thought was to buy a salvaged Leaf for $6k-$7k and use that as a donor. Another was used parts from ebay, other enthusiasts, salvagers, etc. To keep the impact of battery bill low I was considering starting with enough cells to be able to start it and get it rolling then add cells as I wanted/could afford more power. The cells would be in the back between the chassis rails. There is no bed on a race truck only fiberglass sides with a rear cage. The fuel cell is normally back there, the batteries would replace the fuel cell.

My biggest consideration is overall weight. The chassis is a roller (suspension complete) with the rest stripped enough to start cage fab. A race ready cage is going to add 250-300 lbs. I don't yet have a weight on the roller just yet. I plan to compare those to the weight of the Leaf and see where I am. At this point it may be overall weight that tanks the feasibility of the project. A gas powered race truck in this class is about 3400 lbs without drivers, spares or fuel. There have been a couple of EV attempts at desert racing (including one at the Baja 1000 this year) and I'm looking at how they've done it as well.

Thanks!
 

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Discussion Starter #2
It took 10 days or so to get the post approved. I've done a ton of research since then and started following salvaged Leafs at Autobidmaster.com.

I'd still like to hear some comments/advice/criticism. I'm not seeing the Leaf viable for this project. Due to the relative simplicity of the power requirements dealing with the related modules other than what drives the powertrain is adding unwanted complexity. It would be one thing were it a street car with all the accessories. This is basically a race truck though. I'm seeing a better approach being build bare bones with parts and open source controllers.

Weight is what is going to make or break the project. Suspension wise the truck is capable of getting 4-5' of air. With too much weight it won't be able to leave the ground and may negatively impact handling. Still have a lot of work to do planning to see if it's suitable for this type of build.
 

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Got one but it's an 88 street runner/commuter.

Score a motor then decide on everything else. Volt batteries can shed a bunch of weight if you unpack them and reassemble. Packs as removed are 400 lbs, Yabert got his down to 88lbs but I'm not sure how safe for your application. Not sure if tesla packs are sturdy enough.

Your current tranny might last 15 minutes, but depending on motor, you may not need one. You will need a 4wd box out of something beefy the 13-40 series is ok, but not rated for the torque you'll make.

Oh and all the" experts" should show up soon to help you along. GOOD luck there
 

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Thanks. It's only 2wd for this class. I can fabricate rugged battery housings no problem but it would likely have to be externally cooled. Info on the buggy that ran the 1000 this year is hard to come by. The team and builder are in Baja aren't part of the online off road social scene.

I suppose I'm looking at it bass ackwards. Now that you mentioned it I do notice that the build threads generally start with a motor and work from there. I was designing around the battery and controller for range and weight and building from there. That's where the bulk of my research and napkin sketches are. I'll start from the motor end and work the other way and see where that leads me. Though I have the trans I doubt I'll need it after a few weeks looking into it. If it were a street build there are a lot of good EV Ranger examples. I think once I can get to the point where I can get the weight/range issue designed I'll have a better idea on what it will take. I see me blowing right by the $10k build goal though.
 

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Nah, I only did $10K buying all new stuff: motor, adapter, controller, FLA batteries. I don't weld for poop, and have no access to machine tools anymore.

Stuff can be had cheaper now.

The only advantage to looking at street builds is that they show you basics of where/ how to put components.

There were a couple of rock crawlers on ths site until the new owners messed everything.
 

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Reading your original post - If you keep the ranger mostly stock you will need 60kwh of battery to hit 60 and run 100 miles in an offroad baja type event... maybe more.

To me the only crack you have at doing this is to get rid of most of the Ranger.
Start with the bare rolling chassis (throw the trans away too). Weld on roll cage keeping weight in mind, add fiberglass body and aluminum interior, aluminum seat. The Ford 8.8" rear end I believe the highest ratio you can get for that is a 5.71? You will need this to run direct drive to the motor. IF not you will have to keep using the transmission

Like most people on the forum, a forklift motor 11" or so would do the job direct drive. acceleration won't be incredible, but if you've kept the weight down it should move out just fine with a 1000A controller.

For batteries - two complete Chevy Volt packs would likely do the job - throwing out the 1kwh modules you'll have 28kwh worth of 2kwh module - These you'll want to tie together 4 in series so you end up with a pack that is 3 banks of these wide totaling 24kwh and around 200V. You may need to drop down to 3 series and 4 wide to keep within a reasonable controller cost - a ZEVA 1000 would work (max is 175V?). Parallel them carefully through the original BMS ports, and tie to your BMS. Mount this mess of a battery where the box of the truck used to be - and you are all set for well under $10k! Good luck!
 

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Discussion Starter #7
Like most people on the forum, a forklift motor 11" or so would do the job direct drive. acceleration won't be incredible, but if you've kept the weight down it should move out just fine with a 1000A controller.
Thanks. It's more likely to have a 9" Ford rear end. That's the common part not only in race but specifically in off road racing. You can get to a 6.50 if needed.

In working out battery placement they're going to have to go more toward the front if not outright in what would have been the engine compartment. The motor can easily fit in the trans tunnel with some mods. On a short bed there isn't enough distance between the cab and the rear axle to get the center of gravity in a place where it's not going to tank the handling and how the rear suspension performs. That's where I'm at now, seeing how to balance the battery and motor weight in relation to how a race truck should handle using an 11" DC motor and the Volt packs.
 

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Could split your pack between the "bed" against the rear of the cab, and the engine compartment. That plus the motor in the trans tunnel gives you room to fine-tune weight balance a bit.

Can you put some numbers to the weight concerns? What is your ideal weight budget for batteries? It can be difficult to get both cheap & light. For example ~26kWh of Tesla modules runs close to $8k and weighs 275lbs. While 27kWh of volt batteries cost more like $3.6k but weigh ~500 lbs (before you start stripping them down). You should also consider current limits (and C rating)for the batteries you are deciding between. When I was planning my build, I made a small spreadsheet to compare price, price/kWh, voltage& current limits, weight, and volume. That helped me figure out what made sense for my goals and I'd recommend it. Another one to consider for high-current applications is these LG Chem batteries, which I noticed EV West used in the refresh of their pike's peak racing M3.
 

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Thanks. It's more likely to have a 9" Ford rear end. That's the common part not only in race but specifically in off road racing. You can get to a 6.50 if needed.

In working out battery placement they're going to have to go more toward the front if not outright in what would have been the engine compartment. The motor can easily fit in the trans tunnel with some mods. On a short bed there isn't enough distance between the cab and the rear axle to get the center of gravity in a place where it's not going to tank the handling and how the rear suspension performs. That's where I'm at now, seeing how to balance the battery and motor weight in relation to how a race truck should handle using an 11" DC motor and the Volt packs.

I guess I misread the original post - it sounds like the ranger already somewhat exists as a racing truck, which is a step in the right direction. If you already have the 9" rear end that is definitely the ideal unit. Personally I would go a step further and get into a quick change so I can adjust ratios in a matter of a few minutes!

As bawfuls mentions you may want to divide the pack up and run some of it up front and some in the rear. Ideally you would not want to parallel modules but it is really the only way to get the current draw from the lower voltage to keep it powerful and somewhat inexpensive (using Volt cells). Since they have become more common I'm surprised the 24V 5kwh Tesla modules have not dropped in price much... still about $1000/piece. 5 or 6 of those in series would be ideal.
 
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