Conversion Budget Question

Technical discussion on converting internal combustion to electric
Post Reply
syahrr01
Noobie
Posts: 2
Joined: Wed, 14 Oct 2015, 15:19
Real Name: Rama
Location: Melbourne

Conversion Budget Question

Post by syahrr01 » Wed, 14 Oct 2015, 22:46

Hi All,

I've always had EV conversion in the back of my mind for years. Last time I looked at it (years ago), batteries cost/weight made it unrealistic for us. Hoping new development in battery technology and economy of scale have changed that.

So here's our requirement:
(i) Donor vehicle is a medium sized 4 door sedan. Curb weight with ICE is 1,500 kg
(ii) 80km/50miles range maximum. Average usage is only 30km per day.
(iii) Stop-go traffic mostly. Flat terrain.
(iv) Don't need to go beyond 100kmh/60mph
(v) Would be nice to replicate current ICE performance (0-100 around 8 seconds)

How would you approach such a conversion? Given the requirement, DC would suffice and be more cost effective? Direct drive or keep gearbox?

How much would you budget? Are there any professional garage offering conversion services?

User avatar
jonescg
Senior Member
Posts: 2817
Joined: Thu, 21 Jan 2010, 23:05
Real Name: Chris Jones
Location: Perth, WA.

Conversion Budget Question

Post by jonescg » Thu, 15 Oct 2015, 04:18

The best advice is don't set yourself a budget - start designing and then see what it costs. If you don't like the number, lower the specification. If the lower spec doesn't satisfy, don't proceed.

Personally I would go for an AC system despite the slightly higher cost. Direct drive instead of gearbox, and go for a decent battery chemistry. Ballpark figure would be around $25,000 give or take.

Make it good and you will be happy with the result - the dollar value is sort of irrelevant with these kinds of projects. Make it compromised and you'll start to question why you did it, and whether it was worth it.

I've never done a car project, but my bike was a $45,000 project and I still believe it was worth every cent and more Image
AEVA National Secretary, WA branch vice-chair

User avatar
Johny
Senior Member
Posts: 3729
Joined: Mon, 23 Jun 2008, 16:26
Real Name: John Wright
Location: Melbourne
Contact:

Conversion Budget Question

Post by Johny » Thu, 15 Oct 2015, 13:46

My initial reaction is that your donor is too heavy - unless it's a classic. Modern car powerplants are relatively light so you won't lose as much weight as you would with older cast iron block and head engines.
You distance requirements indicate that you want a power-dense battery pack so I'd be looking at Leaf cells or Headways.

I agree with Chris in that AC will give a much better long-term result but will be more expensive in the short term (once you have replaced a DC controller or two it might start to look the same economically).

Why such a heavy donor?

syahrr01
Noobie
Posts: 2
Joined: Wed, 14 Oct 2015, 15:19
Real Name: Rama
Location: Melbourne

Conversion Budget Question

Post by syahrr01 » Thu, 15 Oct 2015, 17:34

I know the donor car is not ideal. It's heavy, FWD, parts are becoming difficult to get, and will be a nightmare trying to integrate/stub the CANBUS system. It has zero resale/economic value and I doubt if it will ever be a classic. BUT our family do have a strange emotional attachment to the damn thing, particulary my wife and son.

This thing will only be driven once a week, not sure if I want to sink 25k into it to be honest.

Sounds like the concensus is AC. Trying to keep to cost down, what motor/controller combination would you recommend?

User avatar
offgridQLD
Senior Member
Posts: 1825
Joined: Tue, 23 Jul 2013, 16:05
Real Name: Kurt
Location: Fleurieu Peninsula, SA

Conversion Budget Question

Post by offgridQLD » Fri, 16 Oct 2015, 01:11

To spend 25K...most likely more. On a old front wheel drive 1500kg sedan sounds mad to me. Unless you are just looking for something to tinker with and have cash to splash.

You could by a 2nd hand Nissan leaf for that kind of money. That's a 1500kg front wheel drive family car. The home build EV wont have the same refinement, reliability and safety as one of the major OEM EV"S. Particularly when starting with a Old ICE car and a limited budget.

If it was a classic car, Custom built car or some kind of race car. I can understand but by the sounds of it it's just a run of the mill family sedan.

But hey it's not my money or car.



Last edited by offgridQLD on Thu, 15 Oct 2015, 14:13, edited 1 time in total.

User avatar
jonescg
Senior Member
Posts: 2817
Joined: Thu, 21 Jan 2010, 23:05
Real Name: Chris Jones
Location: Perth, WA.

Conversion Budget Question

Post by jonescg » Fri, 16 Oct 2015, 04:31

^^^
True that - a conversion project nowadays needs to be something special. There's just no need to do a daily driver on a budget, given you can get a used leaf for about $25k, or iMiEV for $18k which would meet all your objectives.

But if it was an all wheel drive 460 hp CRX conversion, then sure Image
AEVA National Secretary, WA branch vice-chair

Bryce
Groupie
Posts: 209
Joined: Sun, 13 Jun 2010, 16:54
Real Name: Bryce Gaton
Location: Melbourne

Conversion Budget Question

Post by Bryce » Sat, 17 Oct 2015, 00:28

Hi there - having done several conversions (including a couple of AC vehicles) - my vote is ............ for the money it costs to do a good conversion, buy a Leaf! Great all-round family car. And its cheaper than the conversion. And it's way quicker to do. (And guess what I drive now :)

Cheers
Bryce
Last edited by Bryce on Fri, 16 Oct 2015, 13:29, edited 1 time in total.
AEVA Vic Branch Secretary
AEVA national newsletter editor
Current EV drives: Kona electric, 2001 Berlingo conversion
Selling: 2011 Leaf
Past drive: 2011 Blade Getz
Past Conversions: DC Berlingo, AC Berlingo, AC Sprinter

User avatar
4Springs
Senior Member
Posts: 553
Joined: Thu, 23 Dec 2010, 01:14
Real Name: Christopher Walkden
Location: Selbourne, TAS

Conversion Budget Question

Post by 4Springs » Sun, 18 Oct 2015, 01:44

syahrr01 wrote:
How would you approach such a conversion? Given the requirement, DC would suffice and be more cost effective? Direct drive or keep gearbox?

You could probably do this for under $20k, if you kept the gearbox and used a medium sized DC motor. But you wouldn't get anywhere near the performance mentioned in (v). You'd get the speed but not the acceleration. As mentioned elsewhere the killer is the weight - unless you know this is mainly in the bits you will remove (seems unlikely).
My guess is that 18-20kWh of battery would do you. This would be fairly large and fairly heavy unless you use the more expensive cells - do you have somewhere to put it? I assume it seats 5 - are you able to re-purpose some of that space to make way for battery? (i.e. turn it into a 2 seater so that the space and carrying capacity can be used for battery)

I'd tend to agree with others that it wouldn't be an ideal donor for a conversion. But sometimes you just have to work with what you have!

Post Reply