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Discussion Starter #1
Last couple weeks, I am train to figure-out how to built my everyday/track day sports car, but now I not shore what to do. :(

First off, I would like to go with Tesla rear big unit, Tesla battery packs etc (some nice people here give me some great inputs - thank you all).

So what to do about donor car? I tough Nissan 370Z was perfect for this conversion, but it is to heavy and rear part of the car is to expensive to customize so Tesla unit can fit.

So what to do? Which two door sports car to consider?

Budget for donor car (flooded, engine or gearbox dead, light damaged etc) is around 15K euro.

My idea was Porsche Cayman, or 2000-2002 Porsche 911, or Subaru BRZ/Toyota GT86, or ... I need your help :)

Please help.
 

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Discussion Starter #3 (Edited)
What's your budget for the EV conversion parts?

What's your electrical/mechanical skill level?

What's the minimum performance and range that you require?
Electric part will be done by company that produce low budget EV. For mechanical, I will use local famous company that tune and modifies cars for race.
Budget: 25 do 30K USD
Performance : 0 to 100km/h in 3.5 sec - range in dynamic track day mode plus 20km
 

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Budget: 25 do 30K USD
I suspect that will not be enough for parts and labour given your performance requirements...

Performance : 0 to 100km/h in 3.5 sec - range in dynamic track day mode plus 20km
We know the Tesla large rear drive units have problems with overheating on the track (see here and here). You could consider a dual motor approach using the Tesla small drive units or follow Chris Hazells attempts to split the inverter and stator cooling on the large drive unit.

Have you considered rapid charging at the track so that you can use a much smaller, lighter, and cheaper battery? Lots of tracks have three phase AC available in the pits and you could build yourself a supercharger using recovered Tesla chargers :cool:

I think once Chris's car is racing or we have the 2018 Cobra updates we'll have a lot more knowledge about what really works on the track :)
 

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My idea was Porsche Cayman, or 2000-2002 Porsche 911, or Subaru BRZ/Toyota GT86, or ... I need your help :)
I think the challenge is deciding whether you need one or two motors to meet your performance goals... from what we know today I think it's more likely you'll have success with two small Tesla drive units because of the known cooling issues with the Tesla large drive units.
 

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Discussion Starter #6 (Edited)
Still waiting Chris offer for Tesla unit and parts. Still do not know how much will cost all!

So can you Kevin make me approximately cost estimation for the parts in total without battery - for my request setup?
 

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So can you Kevin make me approximately cost estimation for the parts in total without battery - for my request setup?
I will post a detailed list of my build costs when I get a moment...

Until then, if we assume you're building a twin Tesla motor setup then a quick look at vendors in our list (here) shows the two motors available for an asking price 7250 euros (here) and the inverter controllers 1500 euros each (here). So, if you budget 7250 euros for the two motors, 3000 euros for the two motor controllers, and say another 5000 euros for a charger, charger controller, DCDC, HVJB's, inlet, contactors, etc., you should be ok.

Note, this ~15000 euro estimate assumes you're testing the motors yourself. If you want/need fully tested and supported products then you must factor in additional costs from vendors like Chris. That said, Damien has bare controller PCBs available for 50 euros if you have the skills to manufacture, test, and support the inverter controller yourself. :cool:
 

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So what to do about donor car? I [thought] Nissan 370Z was perfect for this conversion, but it is to heavy and rear part of the car is to expensive to customize so Tesla unit can fit.

So what to do? Which two door sports car to consider?

...

My idea was Porsche Cayman, or 2000-2002 Porsche 911, or Subaru BRZ/Toyota GT86, or ... I need your help :)

Please help.
I don't know why it would be likely to be easier to stuff Telsa drive unit into the back of a BRZ/FR-S/86 than into a 370Z. Neither one is designed to fit an electric motor in the area of the rear axle, or to have any mechanical part extending rearward from the rear axle line. The BRZ/FR-S/86 might be relatively cheap, but it is small; that's what you want, but it also means that fit problems could be greater than with larger "sports" cars. There have been Tesla installations (well, at least one) in the Factory Five 818 kit car, which uses a Subaru Impreza rear suspension like the BRZ/FR-S/86, but the 818 uses none of the stock suspension arms and nothing like the stock subframe.

A Tesla drive unit might fit in fine with the 996 (1999-2004 911) or 993 (1995-1998 911) rear suspension, but it should definitely fits with the 964 (1989-1994 911) and earlier rear suspensions. Of course, the older design (964 and prior) is an inferior suspension, and older cars are more rusty.
 

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Ok, lets forgot Tesla for the moment. Which car to use than? Which motors and controllers, any suggestion?
A complete drive unit with the motor in front of the axle changes the packaging issues in a typical front-engine and rear-drive car, but still isn't easy - I can't think of anyone who has done it. The most popular candidate discussed for this would be a Nissan Leaf unit.

Many motors have been used in place of an engine, or in place of an engine and transmission. The Leaf motor with inverter, but without the transaxle, is perhaps the currently most popular of modern salvaged EV motors, but even that is rare; there's an example shown in another thread. A problem with this approach is that it usually (as in that example) means a motor occupying the original engine space in the front of the car, and not much room left for battery.

If you're sacrificing the rear seat space, a typical 2+2 sports coupe might fit the motor and inverter in front of the stock final drive unit (differential), leaving the front compartment entirely for batteries. berlinger did this in his Latvian mazda RX-8 project, but the idea would work equally well (and have similar challenges) in other cars.

A natural fit would be to use a mid-engined car, replacing the transverse engine and transaxle with a motor and transaxle unit from an EV (such as a Leaf). There have been many Toyota MR-2s converted, but with that model and the other mid-engine cars of the era (Fiat X1/9, Pontiac Fiero) long out of production, cars to convert are now rare. Of course you can use a Lotus (like the Tesla-powered Evora), but most people don't have the budget to start with a Lotus (or Ferrari, or whatever); recently, there have been no reasonably-priced cars using a mid-engine layout.

There are many kit cars intended for mid-engine installations; any of them could work for some variety of EV conversion. I mentioned the Factory Five 818 (intended to have a Subaru engine and transaxle) built with a Tesla complete drive unit, and when I just did a quick search, I found that many people have at least discussed this particular model and a few actually get built. Packaging batteries is still a challenge, since if the motor is put where the engine belongs, the remaining space around the motor, the fuel tank space, and the trunk(s) usually don't provide good space for a battery pack and it ends up being in a bunch of small boxes all over the place. For the 818, and probably other mid-engine kits with tubular steel frames, the Tesla drive unit is probably the way to go if you can make the suspension work (leaving the entire space ahead of the axle for battery).
 
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