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Discussion Starter · #1 ·
The Project:
I retired in 2005 and had several projects I wanted to attempt. When gas prices spiked to around $3/gal the first time back in ‘05, I came up with an electric car design I thought looked pretty neat, all electric, maximized for battery space. But the more I researched, the more it just looked like it wasn’t cost effective. Then gas prices came back down, and the project got put on the back burner.

Now gas prices are back up, battery technology looks good and getting better. I think now is as good a time as any to get started.

Originally, I wanted to build a all custom fiberglass shell on a steel tube frame and try to keep the weight around 2000lbs. But since I would like to get it finished in a “reasonable” amount of time, I decided to find a car that would fit the budget and be close to my original design. I found the second generation (2G) Eclipse / Talon was pretty close, so I bought a ’96 Mitsubishi Eclipse locally for $1300 bucks, ICE still in good shape. I should be able to use most of the interior from the firewall to the B pillar, and the transmission and suspension will remain (with appropriate mods, of course). The structure will have minor roof mods, and essentially everything ahead of the front wheel and behind rear wheel will be changed, and part of the floor will be cut out between the B pillar and rear axle for the batteries (reinforcement of the structure will be steel and/or fiberglass). The rear seats will be removed and the hood, front fenders, and rear hatch will be replaced with fiberglass. All the glass behind the B pillar will be replaced with plexiglass (or similar) and I will also attempt to make custom headlights and taillights.

Goals for the car:
Has to look good. To me, cars should be functional art and should be a conversation starter with other car nuts.
Most of my trips in this car will be errands, less than 10 to 15miles, but a range of 40+ would be sweet, mostly at city speeds but highway speeds for a few miles will make it more functional. Yearly miles probably 4k or less, but really depends on how much fun it will be to drive.
I want decent performance, 0 to 35mph in less than 6 seconds, 0 to 60 in less than 15 seconds.
Weight of close to the original, ~2800lbs or less. I removed the spare tire, jack and interior behind the B pillar and weight is already 2625lbs in current ICE configuration (before any other modifications). The hood is 37lbs and rear hatch is 72lbs, both to be replaced with fiberglass. Remove ~550lbs of ICE parts, chop may remove an additional ~150lbs+??, so 2500lbs may not be an unreasonable target.

EV Equipment:
A bit early for motor, controller and battery decisions just yet, but probably a WarP 9 with a 1000 amp controller or something that will get similar performance. If I could make it less than 2500lbs, the AC50 might be an option and still meet my performance goals, but I don’t see getting it that light.
I’m open to any battery chemistry that can deliver at least 60 kw for at least 20 seconds even at low SOC, but max weight of ~900lbs (for max rear axle weight) and they’ll have to fit between the B pillar and rear axle. I’m going to try to build the battery box to accommodate 12 group 31 size batteries, but most likely will go with 36 to 40 CALB 180ah or whatever may be best this time next year (at the earliest).

What I’ve found so far with the Eclipse:
The Good:
A neat looking car (a high priority for me)
There’s a bunch out there and a lot with bad engines (I guess due to the timing belt) so you can get them pretty cheap, and a high percentage have manual transmissions.
A good drag coefficient (.29 according to the technical manual, but likely worse with my chop)
DSM forums have a lot of good info, very popular car with the tuners (DSM made the Eclipse and Eagle Talon).
Lots of aftermarket and junk parts
The Bad:
If you look at the some of the plastic wrong, it will break (door handles on several I looked at were broken off).

There is no real timeline for the project, but if I can get it finished before December 2011 and still get some tax rebates, that would be a goal. The original cost projection was around 15K, but that’s flexible. I’m not beyond saving a buck, but I’m willing to spend more if I think it’s justified.

Car Experience:
In my younger days I repaired and maintained a small fleet of ‘60s and ‘70s era trucks, kept my 1970 Opel GT running, and built a VW dunebuggy rail. I graduated from GA Tech with a degree in Mechanical Engineering and worked for Chevrolet in the mid ‘80s at the Milford Proving Grounds. I’m a retired owner of a HVAC company and have acquired some fiberglass and electronics skill from building a RC vtol aircraft (but that’s taken a back burner to my new desire to build an electric car.)

But I think it’s safe to assume I don’t know what the heck I’m doing, so any tips and tricks would be appreciated.

To Do this week:
I’ve already tested all the components I want to keep or think may be worth selling. I will go through manuals again and attempt to figure out the gauge cluster next week while the ICE is still running, see what it takes to make the tach work. The signal comes from the crankshaft into the PCM with a complex pulse for ignition timing, but I don’t know what goes to the cluster. The speedo shouldn’t be a problem since it comes from the tranny with a simple pulse signal, but it still goes through the PCM before it goes to the cluster. I’ll probably dive into the ac and heat controls since it gets a signal from the PCM. Ideally, I’d like to get rid of the PCM, but so much goes through it, or comes from it, I don’t know if it’s feasible. After that, the ICE parts come out and the chop begins.

Anything else that needs to be done before the ICE comes out please let me know.

Joe (Max) Davis
Valdosta, GA
 

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Discussion Starter · #2 ·
Moving right along

Found the tach signal coming into the back of the cluster to be about 2 pulses per rev, so I guess a standard 4 cylinder tach signal. It's actually 32 hz at ~1000+rpm, it should be 1000rpm/60 * 2 = 33.3 hz, so it's about ~5 to 6% off (similar error further up the rpm scale). It seemed to be dead on with the mph during some tests I ran for the gearing ratios, so I don't know if it's an error or if it's being tweaked in the PCM for some reason. Anyways, close enough.

The signal coming in the back of speedometer is just mph = hz, so that's pretty cool.

The wiring in this thing is unbelivagable. It seems like if there's an empty space, there's a wires going through it. I think I can more easily rewire it than figure out these wiring harnesses. I’ve labeled all the plugs to the devices I’ll keep, but I think tomorrow, the wiring harness goes. I can figure out the few switches and sensors, and will make my own microprocessor control box for the lights, air and heat, etc.

There’s no ABS on this car, I’ve removed the air bags for good (no requirement in GA to keep, that I can find).

The rear has been chopped off, the engine came out today.

The rest of this week and next:
The front will get chopped, the roof will get chopped (just the rear portion).

I’ll post pictures as it gets more interesting.
 

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Discussion Starter · #3 ·
Stripped

After rethinking my to do's from my earlier post, I thought it would be better to finish tearing down the Eclipse, cleaning up the parts I’m going to use, ordering the parts I need to replace, rather than trying to start the roof and front chop.

With almost all parts off the body, it’s good to see there is no real hidden damage or rust. With no parts to obscure my view, I’ve decided to not only cut out the floor for the battery box, I’ll also cut out the floor up to about the dash and replace with steel tube and fiberglass. I can use the extra ¾”+ for headroom, it should cut down on pavement heat, smooth out the floor (and underbelly), maybe even slightly lighter. For a few minutes I thought about chopping everything in front of the firewall and behind the B pillar and going rear drive with a new framework and suspension (Is there a name for this “finding more stuff to do” affliction?) A few quick calcs and it looks like benefits would be small for my application. A few more batteries would be cheaper, easier and overshadow any benefits of going RWD.

Just a tidbit for my earlier post about how much wire is in this thing. Wires, relays and fuses (no PCM or other controllers) is 30 lbs (first picture below). Seems a tad excessive, hopefully I can use less.

I’ll post a more comprehensive weight breakdown later for reference. For now, just some pics in it’s current state.
 

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Re: Stripped

Whoa! That's an ambitious project!
Is there a name for this “finding more stuff to do” affliction?)
In project management it is usually called scope creep. Lay out a project plan with costs and timeline, and see how much time and cost creep upward with each proposed addition. I imagine you have the time and the money. My concern, if it were me in your place, would be that I might loose interest before I finished it, if it were to drag on too long.
 

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Re: Stripped

In project management it is usually called scope creep.
Thanks Tom, I didn't even know it had a name. Just knowing it's a problem other people deal with gives me some hope. :)
Lay out a project plan with costs and timeline, and see how much time and cost creep upward with each proposed addition. I imagine you have the time and the money. My concern, if it were me in your place, would be that I might loose interest before I finished it, if it were to drag on too long.
Great advice. I have a tendency to underestimate my projects, so I just "shot gunned it" at 2500 hrs over 2 years, with a steep learning curve. Hopefully addition of replacing the floor won't add more than a couple weeks with modest costs since I was going to cut part of the floor for the battery box anyway.

And you hit the nail on the head about loosing interest. I fear if it creeps past 2 years, it may never get finished. Although this project I could almost use daily, and it's pretty expensive, so that may give some staying power. I found forum feedback also helps keeps me accountable, so thanks for the input.
 
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