2003 TF 115 EV Conversion Build Log

Immo1282 wrote: Trying to cram a decent hybrid system in alongside the F's engine seems like it'd be a much greater challenge than simply swapping for EV components as in my project! …..

I am planning to utilise the fact that the front subframe on the F/TF is basically the same as the rear subframe and there is plenty of space under the bonnet for a small electric motor, especially if it is direct drive rather than through a standard gearbox.

That makes sense - I guess I'd misinterpreted your plans - cause there's no room for a PHEV style hybrid system with any decent range - but if it's a prius-style supplementary hybrid then that's a lot more feasible. You could build a small battery pack in the spare-wheel well, and if you relocated some of the other under-bonnet parts - a direct drive motor could fit.

I'll definitely be following your project closely as and when

I'm sorry if double-posting is not good etiquette here, but I'd rather not make a new thread for it!

Picked up my TF today. There's a few things that need attention but nothing massive (thankfully...).

• The hood leaks at the back (The panel with the window is torn at one corner), but I need to replace the back window anyway, so can do that job at the same time...
• Someone's bodged an unmarked button to the left of the steering column, seems to activate the horn - and the normal horn buttons don't do anything - so I'll hopefully wire that back in normally...
• A few lights are out (reversing lights switch?, one brake light) so those need fixing.
• Fan seems to only work on settings 3 and 4, and remains off in settings 1 and 2 - Sounds like the resistor pack is partially gone, but I might leave it alone for now as it still works when it's needed and I can't really be bothered to tear apart the interior to fix a mostly-working heater

Apart from that though, it drives beautifully and will convert wonderfully once I get that going.

I would follow the wiring for the horn, it may be a failed relay in the BCU that has failed.

Check out the wiring on the boot hinge, it throughs up some weird electrical issues around the rear lights.

The resistor pack for the interior fan is accessible from the passenger footwell unless you have air con.

Going back to your conversion plans, I am surprised that you

a) plan to keep the gearbox

b) will use lead acid not lithium batteries. i know they are cheaper but the weight and capacity..........

Keeping the gearbox is not a necessity - but I'm mostly doing it to save cost & complexity. As opposed to buying or engineering a custom reduction box - I can use the stock gearbox just always set in 3rd gear for a small weight penalty. Additionally, I've got my eye on a motor that's already mounted to a rover PG1 gearbox from an Elise - used initially in another conversion but later upgraded hence it being spare.

I will be using Lithium batteries - Not sure where you picked up point B from - but my plan is to use around 90% of the battery pack from a Nissan Leaf, for a capacity of around 20kWh and a weight of only a hundred or so kilos. Pb-Acids are dead as far as conversions go, as there is enough availability of used Lithium cells even now to make the slightly cheaper price (of new batteries mind you) irrelevant. Also a factor that kills Pb-Acids is degradation - A lead acid pack will be badly degraded after a few years, whereas a Lithium pack properly looked after could last ten or fifteen.

Anyway thanks for your comment

I know the thread's a few months stale, so I apologise if I'm necro-posting (not sure what the etiquette here on that is...) but I've a small update.

Haven't started working on the actual conversion yet, but I have been doing a few small things around the car while it's SORN;

• Replaced the rear window with the glass heated version from BAS International. Stopped a big leak and is actually see-through now...
• Installed heated seat pads - 50-100W heated seats are way more effective and energy efficient than a 1500w heater (there'll be one there too, but the seats are for comfort. Put the controls for it in the ashtray with a bit of 3D printing and some carbon-fibre vinyl (see attached images)
• Removed the centre console and scraped off that dreadful rubberised finish. It was peeling and ugly before, now it's much better.

In progress of the conversion, I've got the batteries, scaled up somewhat from my original plans - I'll be using around 30kWh of new LiMnCo (Lithium Polymer, same as most OEM electric vehicles now) cells. A "Small" pack over the front axle in place of the spare wheel will weigh around 45kg. and the rest (around 120kg) will be behind the seats in place of the fuel tank. These batteries were sourced from a chap in London who himself got them from a liquidation auction from a now-defunct company manufacturing high-performance (300+kW) sports cars, so they should last for ever in the relatively gentle application of my TF.

I'll update as I make more progress. When I've the £s spare, I will be going to get the other drivetrain bits, but for now I'm content with building up the battery pack in bits and working on small things

Immo1282 wrote: I know the thread's a few months stale, so I apologise if I'm necro-posting (not sure what the etiquette here on that is...) but I've a small update....

Keep it in the same thread, makes it easier to follow.

How do you plan to demist the windscreen if you don't have the heater anymore?
I have a heated front screen to take care of that, as well as heated seats.

talkingcars wrote: How do you plan to demist the windscreen if you don't have the heater anymore?
I have a heated front screen to take care of that, as well as heated seats.

I was a little ambiguous... I will be replacing the MG heater core with an ceramic heating element (designed to run at mains voltage) directly off the high-voltage battery. That way I can use it to clear the windscreen/warm the cabin up for a few minutes as needed and then turn it off to conserve range.

The PTC ceramic elements are also good because temperature control is pretty unnecessary as their resistance increases a lot as they warm up - i.e. you can control their heat output and power consumption based on airflow - A control the car blower already has.

Really interesting thread - i'm considering converting a Morris Minor i'm restoring to electric, but an electric TF would be appealing. What do you anticipate the conversion will cost? i've heard figures of £20k to £30 bandied about just for the parts, but as you can buy a second hand Nissan Leaf for under £10k if you look around ( which appears to be very popular as a donor car) i'd be interested to know how the costs break down.

So far I'm trying to do it for under 10k - but in reality it's probably closer to 12 including the car. I can recoup a bit of cost in selling the engine, and other ICE bits that I don't end up using.

£20-30k in parts sounds like a high-performance "Tesla Swap" type conversion to me. I spent 3.5k on 30kWh of batteries - it's common for Tesla battery modules to be £1200-1500 each and that's only 5.2kWh. A Tesla Motor and motor controller could be £10-15k all in, whereas I'm sourcing a motor and motor controller second hand for around £2500 all in...

Used parts (as I'm doing) is much less expensive. I'm trying not to cut too many corners, but I don't want to spend infinite money doing it all the same.

Here's a spreadsheet of my estimated cost breakdown. Will probably overrun this but I'll update it as I go.
https://drive.google.com/open?id=1sZ-jvJrLv4vlW7Pi2y9mk04tIBxcDIRqjI4GBAhnI3Q

edit: fixed the link

I hope to produce my hybrid for a few hundred quid...…..