[SCEV]

I'm brand new to electric cars (got the bug after seeing the Tesla Model S), and after doing a fair amount of research have decided to start a conversion! I've been searching for donor car options non-stop for the last week or so, and think I've finally decided on the Porsche 944. However, I've found that the model changed in 1985 (new control arms, updated interior, etc.) and added about 150 lbs to the curb weight. I've also toyed with the idea of the 1990 convertible model , but didn't know if that would reduce the trunk space for batteries.

Does anyone have experience/knowledge with these specific cars? I'm looking for some advice on whether to go pre/post 1985, and also if the convertible would limit my options.

Thanks,
Scott

[PThompson509]

Hi Scott,

The 944 is a good car to convert - it is a strong car, and parts are available. Not sure about the size constraints of the convertible - those are kinda rare.

For a very nice example 944: http://evalbum.com/3898

From what I remember when I was looking at the 944, the steering update is a good thing, the interior update was not that big a deal. I wouldn't worry too much about the extra 150 pounds - the car is already at 2600 pounds.

Any idea on your budget?

Cheers, Peter

[SCEV]

Thanks for the advice and link (it was a 924, but close enough). I found a few 944's on EVAlbum.

My budget is 15-20k (including donor), and I'm hoping for 0-60 in 6-7 seconds, range of around 80 miles, and top speed of atleast 90. So the cheaper the donor, the better.

I test drove a 87 944 N/A yesterday that the guy wanted $4k for, and am going to look at a 90 944 S2 Convertible for $6k this weekend. My wife really wants to get a convertible, but I'm not sold. I'm hoping to find a decent body (preferably black on black) that has engine trouble so I can get the donor a little cheaper, but no luck on that yet.

Also, I got a tip that I should be looking for a 944 Turbo (951) as the donor, since that has a stronger transmission. All the turbo models I can find are rather expensive though...

[PThompson509]

Turbo transmission won't be necessary unless you are going to put in something monster-sized like 11" or greater. As you mentioned, it really boosts the price.

As usual, before you convert it, make sure the 12v system works perfectly - you wont' want to debug it later. Also make sure the body is in good shape, as you won't want to fix paint / cosmetic issues later.

Top speed of 90 is doable, since you are keeping the transmission.

To get 0-60 of 6-7 seconds, you're going to need a rather strong motor - perhaps the Warp11. I don't think the Warp9 will do it (but I could be wrong).

To get 80 miles, let's do some math:
Assumption: 300 wh/mile.

80 mi * 300 wh/mi = 24000 wh = 24kw.

That is how much usable energy you need. However, you can't use the entire battery without damaging it. So what you need is at least this:

24kw = pack * 0.8. Pack = 24kw / 0.8 = 30kw.

Depending on your controller, that will determine the pack voltage and from that, the pack Ah.

Example: 120v pack, 250Ah. I'm not aware of any 250Ah batteries tho - so you'll need to a different size: 200Ah (for less range) or pairing 130Ah batteries to get 260Ah.

Cheers, Peter

[rwaudio]

Originally Posted by SCEV

Thanks for the advice and link (it was a 924, but close enough). I found a few 944's on EVAlbum.

My budget is 15-20k (including donor), and I'm hoping for 0-60 in 6-7 seconds, range of around 80 miles, and top speed of atleast 90. So the cheaper the donor, the better.

I test drove a 87 944 N/A yesterday that the guy wanted $4k for, and am going to look at a 90 944 S2 Convertible for $6k this weekend. My wife really wants to get a convertible, but I'm not sold. I'm hoping to find a decent body (preferably black on black) that has engine trouble so I can get the donor a little cheaper, but no luck on that yet.

Also, I got a tip that I should be looking for a 944 Turbo (951) as the donor, since that has a stronger transmission. All the turbo models I can find are rather expensive though...

Welcome, glad to see you made it to the forum.
It's not hard to swap the transmission if you need to. (it has to come out to remove the gas tank anyway) My 944 is a NA with a turbo transmission, not sure why the 1st owner did it back then but I'm not complaining.

I should come in a bit under my evalbum estimate for cost since I got a good deal on my A123 cells. It should be under 20k including the donor. I will only have 50-60 mile range though but should around 5 seconds 0-60.

Early on I talked to a bunch of the 944 guys who swap in Chevy V8's and use the Turbo transmission with upwards of 400-450ft-lbs of torque and no problems. A few of them said they had blown up NA transmissions with an estimated 300ft-lbs. Electric won't be the same but if you use a 1000A controller and a 9-11" motor the turbo transmission can't hurt, with a 500A controller the NA transmission might do the trick.

I'm converting an '86 but I also have an '83 that I put the engine out of my '86 into, I can say for interior alone get the 85.5+
The pre 85.5 has the interior from the 924 which is a mid 70's design that i'm not so fond of. The post 85.5 has an interior that most people I've shown the car to think is mid 90's. The driving position (mainly gear shift/center console) is much nicer in the 85.5+.

Since you have already driven an '87 simply go find an early car to drive to compare driving feel and interior and i'm sure it will be an easy choice.

The problem with 944's is they can be a money pit if not maintained. I wouldn't suggest going with the "cheapest" 944 that you can find, especially if it has engine trouble and you are not able to drive it. There are dozens of stories of the $2-3k 944 costing $10k to make a reliable daily driver. Many of the problem parts go away in an EV conversion but not all of them. Get a solid car to start with and you will be happy with it as an EV. There is no point putting 15k worth of parts and a huge amount of labour into a shitty donor.

Rennlist.com is an awesome resource for 944 knowledge and help, I found it invaluable for general 944 knowledge and questions.

Good luck with your conversion!

[SCEV]

I finally found a good donor...1986 Porsche 944 Turbo!

I've got the engine/turbo for sale on Rennlist (Porsche enthusiast forum), and a guy asked me if the DME/KLR (computers) come with the package. Does anyone know if I need to keep these for any reason? Same goes for the engine wiring harness...do I need to keep that?

[rwaudio]

Originally Posted by SCEV

I finally found a good donor...1986 Porsche 944 Turbo!

I've got the engine/turbo for sale on Rennlist (Porsche enthusiast forum), and a guy asked me if the DME/KLR (computers) come with the package. Does anyone know if I need to keep these for any reason? Same goes for the engine wiring harness...do I need to keep that?

I replied to your message, but thought it wouldn't hurt to be posted here for others interested in a 944 conversion.

The DME/KLR are not required in an EV, but it doesn't hurt to keep part of the engine harness, the 14? pin connector from beside the fuse block gives you easy access to gauge inputs and is long enough to run to your controller if mounted towards the back of the engine bay. I'll have to confirm but I believe I also got switched power and start signal from that harness that I use to power the Soliton1, although there is a ground wire listed it didn't work reliably and I had to run a dedicated ground wire to the Soliton1.

I'll take some pictures of the part of the harness that I kept to make it a bit clearer.