[Baratong]

I'm converting a 1979 Triumph Spitfire to electric. Seeing the other Spitfire conversions here, it seems to be at least a mildly popular choice.

For me, when I thought through what donor to pick, I decided I wanted something with some classic style, preferably convertible, 2-seater, and fun to tool around in. I narrowed my options down to 60's to 70's Fiat, Triumph, or MG.

I looked for a few months for an appropriate donor and finally found this 1979 Triumph Spitfire. It has a relatively decent exterior, non-functioning ICE, and overall was in decent enough condition. (I didn't want to embark on a complete restoration project.)

I began acquiring major components saving them for the day when I would have the time to put into the conversion. I've still got quite a few of the minor components to buy and piece it all together.

I've read most everything I could get my hands on about doing a conversion and I've followed these forums for a while -- which has been an unending source of inspiration, and based on how top-notch the work is in quite a few of the builds, it's also been humbling to watch the masters at work.

Builders like evmetro, steelneck, toddshotrods, favguy, skooler and others have shown me how good a quality, creative build can be.

And of course the other Spitfire builders, Moltenmetal, ClinkK, Bottomfeeder have provided quite a bit of information on the specifics of converting a Spitfire -- which is extremely helpful!

I see my build being an evolution. I don't see, or necessarily want it to end. I'll get to my first 'completion' point and I'm sure I'll have many ideas on how to make it better. So it will continue to evolve.

That being said, the design decisions are based on many factors, not the least of which are budget, time available, skills and tools for the mechanical fabrication, etc.

I've been an electronics engineer for over 30 years, specializing in embedded product design including both the hardware and software. So I just couldn't leave the electronics alone. Along the way, part of my build will be about designing major electronic components of my own for the build, and build in as much style and uniqueness as possible.

I'm a lot less confident on the mechanical fabrication side of the build. I've been a bit of a 'gearhead' my whole life, but it's not my first language. So on this part I tend to plan, plan, plan, plan and re-plan before making a move -- which stretches the timeline.

During the build I welcome all suggestions, comments, etc. that will help.


Here's the donor. The picture makes it look better than it is, but its certainly not bad.. more on the donor in the next post.

Pic with the hard-top on. ( I had just moved so lots of boxes in the garage at the time!)

A little more moved in.. but conversion hadn't started yet.

 

[Moltenmetal]

Your donor looks beautiful...I suspect you'll be done before me, because mine will continue to consume my life with rust repairs...

Keep us posted! Looking forward to seeing it progress!

 

[Baratong]

Your donor looks beautiful...I suspect you'll be done before me, because mine will continue to consume my life with rust repairs...

Keep us posted! Looking forward to seeing it progress!

Hey Thanks! I've followed your conversion and really like the direction you're going with it. I'm interested to see how much you like the AC motor.. it should be pretty peppy in a car this light!

On the donor, I'm in Phoenix and this car spent its entire life here in the southwest so there isn't any rust on the exterior. There was a little rust on the interior specifically on the seat frames and under the carpet. It appears that the car took on some water (rain possibly) a few times in its past, but it's so small it's nothing to complain about.

Also, getting into it, it appears the car has been in a pretty bad accident fairly recently. There is a fair amount of frame work and welding on the front end, and that would also explain the 'insurance adjuster special' quality of the new paint job.

First pic is of the partially fitted motor that was in the car when I bought it. It's a Ford Zetec that was only partially mounted. The prior owner had attempted to fit this into the car, got partially through the project and had to sell. So first task was to remove it.

There were some modifications to the frame to make room for the Zetec and tranny but it looks like the mods are sturdy enough to not need to be fixed.

Second pic, ICE removed. The firewall was cut up pretty good to make room for the Zetec, so that will need some patching.

 

[Moltenmetal]

Hopefully you'll be able to get a few bucks for the ztec engine- I got nothing for ny 20r, but the tranny plate from CanEV saved a heap of time.

Yous looks to be in very good shape- don't sweat the accident, as the frame is pretty sturdy And easy to fix- you might have minor alignment problems but mine was hard on front tires too so who knows? Don't sweat the firewall either, as there's no more fire risk! You'll be glad to be rid of that 80 pounds of gas behind your back, separated from you by the seat and a piece of vinyl- covered 1/8" pressboard...you'd figure an electric conversion of this car would be far cheaper to insure on that basis alone...

Keep us up to date with the pics- my batteries come soon!

 

[Baratong]

Hopefully you'll be able to get a few bucks for the ztec engine- I got nothing for ny 20r, but the tranny plate from CanEV saved a heap of time.

Yous looks to be in very good shape- don't sweat the accident, as the frame is pretty sturdy And easy to fix- you might have minor alignment problems but mine was hard on front tires too so who knows? Don't sweat the firewall either, as there's no more fire risk! You'll be glad to be rid of that 80 pounds of fans behind your back, separated from you by the seat and a piece of vinyl- covered 1/8" pressboard...you'd figure an electric conversion of this car would be far cheaper to insure on that basis alone...

Keep us up to date with the pics- my batteries come soon!

Thanks! The frame does look quite sturdy and the work was professionally done so I'm not too worried about it. Yes, the gas tank nearly right behind the seat separated with nothing but the thin pressboard was alarming to see! I don't think I'd want to drive this car in it's original ICE configuration!

What batteries did you order, and how do you plan to mount them? I'm looking at putting most of my batteries up front under the hood with 14 or so mounted where the gas tank was.

 

[Moltenmetal]

32 x180 Ah Sinopoly cells. Bought it all from CanEV which is an easy option for Canadians- in the US you have more choices without having to worry about paying importation twice. People seem to favour the CALB cells at the moment but CanEV has a lot of Sinopoly cells in service so I'm not concerned. The plan is for 18-20 up front, (The Bumblebee fit 20 so I might try that) plus ten where the gas tank was, and either 2or 4 on either side of the spare. But not doing anything with boxes etc until I have the cells, which should be next week.

 

[Baratong]

I chose a Warp9 motor for my conversion for various reasons.

After looking into transmission options, and talking to several other Spitfire owners who converted I decided on going with direct-drive on this conversion. This car is very light, the Warp9 has good torque, and going with a traditional transmission + adapter plate/coupler would require a large chunk of change. I've read and have been told that the original Triumph transmission has trouble handling the torque from the Warp9, and I've seen examples of the carnage that can result inside the gear box.

Also, Phoenix is very flat. You have to go looking for a hill around here. The biggest hill I'd have to go up with this car is the freeway on-ramp. Given that, I feel that the disadvantages of going direct drive are small enough to make it a viable option for my particular circumstances.

So, I did the CAD work for a couple of adapter plates that will let me attach the Spitfire's tailshaft to the Warp9 and had them machined.

After unbolting the original tailshaft from the transmission, I then bolted the adapters and tailshaft onto the Warp9. I kept the shifter because I'm planning to use it to select Forward, Reverse, or Neutral.

And then put the Warp9 in the car.

View from the interior:

Because I'm in Phoenix, heat is more of a consideration than cold (to put it mildly!) So I put a forced-air arrangement on the Warp9.

Next up... Battery Boxes!

 

[Moltenmetal]

See, I told you that you'd likely be done before me!

Looking great- but can't imagine that aluminum for those adapter/ mounting plates was all that cheap, given what I was soaked for a 1/4" x29x 16" plate...I wish you well with your direct drive. Definitely wasn't an option for me.

 

[Baratong]

Well, I'm not so sure about who'll be done first, I've got a long way to go on this one still, and yours is looking well in-hand! With temperatures being what they are, it's hard to get much work done during the summer here. I'm limited right now to getting all the garage work done before about 11am, so the going is a little slow until it cools down.

Yeah, direct drive wasn't my first choice. I read up on the factory trans and it doesn't seem to be the strongest transmission out there . I talked with Daniel Busby (BottomFeeder on this forum) about his experience with his Spitfire/Warp9 conversion. His transmission didn't last very long with the Warp9. I really didn't want to put much effort and money into it if the transmission was iffy for my application.

I looked at fitting a T5 manual at first, then really looked hard at going with a powerglide with direct coupling (no torque converter) and full manual valve body over the last few weeks. Both options would end up being over $1k to complete when clutch(T5), adaptor plate, motor to trans coupling and then a modified drive-shaft to mate with the new trans, are taken into account.

So I settled for direct drive but may revisit it if I really don't like how it drives.

I used 1/2" aluminum for these mounts and it ran about $125 for the raw materials. The whole job was less than $200 (barely). Adding in the reversing contactor ~$150 and I'm in for around $350 overall.

Paul

 

[Moltenmetal]

Regrettably I think you made the right decision- the original gearbox wasn't even up to the job with the gutless little 1496cc engine originally in the Spitfire- mine had 1/2 tooth out of 1st gear when I got rid of it...Fortunately my Toyota 20R was a 2.2L and the tranny is a pretty robust 5 speed- and one which CanEV had mounting plates and couplings to match. Not cheap- way more expensive than what you paid for your waterjet cut pieces and drilling- but totally headache free. My AC50 is only capable of 120 ft-lbs of torque max so I suppose I could have gone clutchless- but shifts would have been slow and that would likely have robbed some of the fun in driving this car- that was a price I wasn't willing to pay.

 

[Baratong]

I have worked on how to mount my batteries. I've got 48 100ah HiPower cells for this build and did a trial fit with a few bits of angle clamped on. I was working out fit issues, and figuring out how the whole thing should go together.

I just noticed Moltenmetal posted how he put his front battery box together and it looks great -- I think I'll do that! Great to have another Spitfire conversion going on at the same time!

So, here's a couple pics of the trial fit of the batteries. Looks like I can fit 25 up front. The clearance on the front three is tight but workable. When I do the actual fit I may not include those just to have a little more room up front.

And from a different angle-

Now to go build the battery box(s).

 

[Moltenmetal]

Hmm, tight but workable makes me a little nervous about mine...your 100Ah cells aren't as tall as my 180Ah. Looks like you front three end up around the same line as mine. How tall are they, and how close to the hood do they come?

 

[Baratong]

I mentioned in my first post that I've been in embedded electronics hardware and software design and development for more years than I'd like to remember.

As a result, I just had to build some of my own components for this build. First up, the battery management system! (Doesn't everyone try building one of these?)

Design goals for this:
Distributed BMS - one board per battery
-Safety, Safety, and more safety!!!
--1. BMS must survive improper installation. If this BMS board is installed backwards on a cell .. nothing happens, doesn't work, but isn't damaged either.
--2. If one fails, the rest of the system including all communications must continue. I used a multi-drop communications system so one failure doesn't phase the rest of the system.
--3. If the cell fails open, there is little damage as in it doesn't catch fire. This is perhaps the worst possible outcome for a BMS board mounted directly to a cell. Full pack current will go thru the BMS board. I've got a self-resetting fuse on this board to help with that.
--4. Any type of catastrophic failure in the system should not damage any other part of the system. On this, no board is electrically connected to the others. This isolates catastrophic failures as much as can be done. Unfortunately, catastrophic failures tend to be, well, catastrophic in their own right.

Other considerations:
-Must use very little current from the battery. This *should* only draw about 5ma at full operation, and I'll write the software to reduce that as the battery charge drops. When the battery starts getting low, this should be able to go down into the micro-amp range by using every increasing sleep/wake cycles to lower the overall draw.
-Reports both voltage and temperature (of course)..
-Active shunting for pack leveling and to aid with charging
-Because this is an evolution, it must be flexible to meet differing needs and experimentation.
--Shunt can be configured for 300ma to 1.4a based on how many of the shunting resistors are placed.
--I wanted to boards to be able to be placed in either Positive up, or Negative up position so when they are on a pack, they are all facing the same direction. A simple stuffing option allows for this selection at build time.

And of course, the real reason for building it is I wan't it to look very cool! (More on that after I build the boards and take a couple of pics)

So, the board was laid out last week, I should have everything in to build up a few on Monday.

Next will be the 'controller' that these talk to, and other items such as a current sensor.

First cut at the board layout on the current sensor is below. It is designed to sense -800a to +800a so it detects and tracks both discharge and charge. This lets it be used as a state of charge monitor so it can drive a digital 'gas guage'.

 

[Moltenmetal]

Jealous of your electronic skill! Very much looking forward to seeing how this all works out for you!

...and if you get a chance to measure the height of your hood at the corners of your front row of batteries as a double-check on what ClintK of the beautiful Bumblebee Spitfire did for me, that would be wonderful- worrying that I may have to jack the hood again, and that's a look I don't want- been there, done that, didn't like the result. Well, an inch is no problem, but I had it up around 3.5" to fit that 20R in there and it looked [email protected]. But glad I didn't put a scoop in the hood, or I'd be undoing that now!

I noticed an unusual black strip along your bumper line- would that happen to be a piece of weatherstripping missing from my car, or was your hood lifted to fit that VTEC engine? And how did they fit that VTEC engine in there without changing the tranny?

 

[Moltenmetal]

Looked up the HiPower cell dimensions- they're around the same as my 180 Ah Sinopolys- 11.1" to top of post. Whew- just put a lot of effort into that box- wouldn't want to have to change it now!

 

[Baratong]

Yes that black strip is weather stripping that gets compressed by the hood when the hood is down.

On the front most battery clearance, the edge closest to the side of the car has about 1.25" clearance between the top of the battery case and the hood. The battery bolt point stands up about an eighth above that so say 1.125" overall clearance. I say 'about' because with the hood down and the sheet metal in that the batteries are standing on it's tough to really get up in there. So there may be about another 16th of clearance.

HiPower has a couple of different models of the 100ah battery. Mine is the HP-PW-100AH, which is 163x51x278mm.. so just under 11" tall on the case, with the extra height of the bolt at about 11.1".

Weather strip picture:

 

[Baratong]

On the Zetec engine, the whole thing fit just barely under the hood so the hood wasn't lifted. The engine was mated to a '79 Mustang tranny, and the whole thing was in the car. The tranny though is quite long and doesn't fit the car well (it has a long tailshaft). There would have had to be quite a bit of modification to the drive-shaft tunnel to complete the install. I didn't want to tear it up like that so just removed the whole thing.

When I bought the car, the prior owner still had the old Spitfire tranny and it came with the car.

 

[Moltenmetal]

When my girlfriend (now wife of 15 yrs) and I moved into our house, my dad and stepmom showed up about 3 days later with a trailer load of stuff from home- including my original Spitfire engine and tranny. We were deep in boxes and renos at the time so I put an ad in the Auto Trader and sold them cheap. Never looked back- no offence to Spitfire restorers, but that stuff was crap! I'm well shot of it. As it turns out, the differential has developed a bad leak, so it will have to come out to have the seals replaced as fluid leaks can be grounds to fail a safety here, so the Leyland demons haven't completely left me yet.

Good luck with your tail shaft- not much to screw up there!

 

[Baratong]

Well, my BMS boards and components arrived late Monday so I didn't build them until today.

Just a few pics of the build-

Front side of boards after applying solder paste:

Next, back side with components placed in solder paste: (That CPU is a QFN-20 and it is real tricky to get down correctly without using solder paste stencils to apply the paste)

Into the reflow oven they go:

Out of the oven, through hole components attached (only top communications connectors), touched up and loaded my software, then attached to a battery:

And a short video of it in operation as the LED cycles between displaying voltage and temperature. The temp is in C, and I haven't calibrated it yet so it's showing a little bit off. Even though it was a warm day in Phoenix, it wasn't 33 on my workbench!



Next up, board for the main controller that these BMS boards communicate with should be in later this week or maybe early next week... then the fun begins writing the software for the whole system.

 

[Baratong]

Just a quick update... I've been sidetracked this week on a few things so haven't done much work on the car. I've got more circuit boards in and am building up the 'control' unit for my BMS. I should have pics of it up and running in a few days.

I did manage to resolve a few decisions this week that I was agonizing over.. glad to be moving forward...

-DC-DC Converter, or dedicated Lithium 4-cell pack?
I chose to go with 4cell 60ah LiFePo4 pack for my 12v system. It's more expensive than a cheap DC-DC converter, but not much different than a higher end unit would be for the amount of power it can put out. I picked up a cheap 4-cell charger so this small pack can charge separately from the traction pack.

-Air conditioning
Since it was 115 degrees (in the shade) here when I was making this decision, I was reminded that the Spitfire would be unusable in the summer if I didn't do something about the air conditioning. I researched 12VDC compressors, and that would be a viable option if this car had ever had air. Since this car has none of the other components for air, it would be an expensive proposition. Sooo, I decided to try using a small home window-unit and adapt it to the car... and use an AC 120v inverter to drive it. (I noticed that 'evmetro' was also going this route on his Eldorado build.) The unit I picked has a remote control that lets you handle all the settings, so the main unit doesn't have to be accessible at all.

-Heating
Nope, decided not to go there. If I move away from Phoenix in the future, I may have to do something about heat. Since it never snows (well twice in the over 40 years I've lived here), and goes below freezing maybe a couple times a year, heating is an option that I can easily do without.

So I got all those parts ordered plus all of the other small parts (contactors, fuses, cables, lugs, etc., etc) this week. Everything should start arriving by the 1st week of August.

In the mean time, I'll have to put some effort into getting the battery boxes built and installed next week!