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Discussion Starter #1
I have a 1962 Sunbeam Alpine sitting on my carport waiting to be restored. I am considering an EV conversion. This will be my first conversion, so please excuse me if I say something obvious as if it were a revelation.

Here is what I am thinking; Tell me if I am crazy:

Motor:
I want to mount a TransWarP9 in the space formerly occupied by the transmission. It will fit, but I may need to provide forced air cooling to the motor.

Drive System:
The turbo400 should couple easily to the propeller shaft with close to the same angle as the original equipment. The differential is a 3.89:1. The manual specifies 17.3mph per 1000rpm.

Batteries:
The batteries can be distributed to three areas. Under the bonnet, behind the seats, and under the boot (where the fuel tank used to be). I should be able to carry 600-700lbs of batteries without over-stressing the suspension or brakes.

Goal:
I hope to end up with a 2-seat convertible with 40-miles of range and a top speed of around 60mph. Primary use will be around town and on country roads. No freeway use is intended. Rapid acceleration is not a requirement. I am trying to compromise between simple and inexpensive so I think I am tied to lead-acid technology for the moment.

Questions:
Is the direct drive system a reasonable idea?
The TransWarP9 direct drive makes things simple. Can I operate at 72V to keep things inexpensive or will low Voltage give me low-speed torque problems?
If 72V is too low then what voltage should I use?
What am I overlooking?
 

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that is a sweet little car for an EV conversion.with the low starting weight of the vehicle it should be a fine candidate for a direct drive system.eliminating the transmission should save quite a bit of weight to use towards batteries.i would shoot for at least 120v.check out the beetles at evalbum.com they are close to that weight.:)
 

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Having owned lots of 20 and 30 year old Japanese cars, and having owned a couple of 30 year old British cars, I would like to respectfully point out that your Sunbeam has a pretty decent resale value :) One of the reasons that we want electric cars is that they're reliable. British cars aren't reliable. They're light, cute, fun (when they're actually running)... and that's about it. If you really want a small old car with no roof, you might look into a Datsun roadster. The British auto industry didn't go out of business because they didn't feel like selling cars anymore. They went out of business because the Japanese showed the world how nice a reliable car could be.
 

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Having owned lots of 20 and 30 year old Japanese cars, and having owned a couple of 30 year old British cars, I would like to respectfully point out that your Sunbeam has a pretty decent resale value :) One of the reasons that we want electric cars is that they're reliable. British cars aren't reliable. They're light, cute, fun (when they're actually running)... and that's about it. If you really want a small old car with no roof, you might look into a Datsun roadster. The British auto industry didn't go out of business because they didn't feel like selling cars anymore. They went out of business because the Japanese showed the world how nice a reliable car could be.
reliability should not be an issue,the ICE and transmission being removed and replaced with an electric drive system would increase reliability.british wiring has a bad reputation,but rewiring a small car of that type is not a huge undertaking.also increasing reliability.:)
 

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reliability should not be an issue,the ICE and transmission being removed and replaced with an electric drive system would increase reliability.british wiring has a bad reputation,but rewiring a small car of that type is not a huge undertaking.also increasing reliability.:)
X2 all the junk that breaks is taken out. One of the main problems with british cars is wiring and leaky oil both of witch should not be an issue.
 

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As long as the suspension, steering assembly and the differential are in good condition it should be fine.

My only problem with your conversion is that you're placing a Warp9 on a car that originally had less than 100HP in it's engine.

This means the Warp 9 at high power could easily destroy your differential.

I would be very careful about accelerating in that car especially because you'll be adding a lot of weight with the lead batteries meaning more stress on the differential.

I myself would limit the maximum amperage on the motor controller to a conservative amount, otherwise you could ruin the vehicle.
 

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what mastiff said.you can reduce costs also by using a smaller motor which could also be used with a less expensive controller.you could still hit the 120v mark as well.:)
 

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Discussion Starter #8
Thanks to everyone for the advice. You raised some questions that I hadn't considered.

As far as the Sunbeam having more value as an original, well... I want the car for me, not for someone else. I have delayed beginning this restoration for several years because I just did not want to put that damn British tractor motor back in the car. I really like the EV idea. The reliability issue has been well answered by others, but let me add this:

"Why are British auto mechanics so mean?
Because they drink warm beer. :)"

"Why do British auto mechanics drink warm beer?
Because they have Lucas refrigerators! :D"


Another point in favor of the Sunbeam, it sits on a true chassis which can be easily beefed up if needed. (see Sunbeam Tiger)

If I destroy the rear end I have quite a few options for replacing it. (Again, see Sunbeam Tiger)

I think the way I am going to proceed is this:
Install the TransWarP9.
Build boxes that can hold enough batteries to go to at least 120V.
Install 6 12-volt batteries and use a 72-volt controller that I borrowed from a friend.

After I test drive the car in this configuration I will have a better idea what I need to do to get to my target range & speed.
 

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X2 all the junk that breaks is taken out. One of the main problems with british cars is wiring and leaky oil both of witch should not be an issue.
You used the word brakes... ;) What are you going to do about those Giring brakes? Just curious. Also, I'm sure you plan on using the differential. I learned to rebuild a differential while I was a British car owner. The diff only had 88k on it. I have never had to rebuild a differential on any other car let alone at only 88k.

In short, removing the engine and transmission does not eleminate all the British parts.

I don't really want to discourage you from building this car. As you're well aware, the car is already super light, so it has huge potential as an EV. You sound like you know what you're getting into. I'm sure this will be a fun car.
 

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Discussion Starter #11
What are you going to do about those Giring brakes? Just curious. Also, I'm sure you plan on using the differential...
The brakes are a concern. Does anyone have a suggestion?

Except for the steering box, this is the same car that carried a small Ford V8 as the Sunbeam Tiger. I have the shop manual for the Alpine, but not the Tiger, so I don't know what changes were made to the suspension, brakes or differential. Web research has not answered those questions either.

I plan on building this in stages. First is a minimal 72-volt system to evaluate acceleration and top-speed. Then I will make a decision on the next step(s). This is a learning experience!!

While I am mostly thumbs (I'm an electrical engineer) when it comes to this type of stuff, my wife is a pretty good welder and body-work gal:cool:. My brother-in-law, who is helping me design and build the conversion, has been designing and building race-cars for 35-years. So I think we have a pretty good team with most of the necessary skills and knowledge.
 

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RFengineers,

I would recomend you look at selling the Sunbeam and using the money to build a different car. If you like the two seat convertable, try an MGB (they are much more common, although an MGB owner would cry sacrilige). There are very few Sunbeams left (Alpine or Tiger).

While I understand that you are building the car for yourself, life will go on and the car will be here when we are gone. At that point someone will probably want to return it to near original condition.

I have had this talk with friends in the past (Shelby GT-350, Piper Airplane). Both have come back later and said they were sorry and wished they had listened. The Shelby was sold for Apprx 1/2 of what a near stock car would have sold for. The piper is currently fo sale, at 1/2 of what was spent on the restoration and upgrade (he was ging to keep this one forever).

Ultimatly you will decide what is best for you. (I listened to people who said they wished the had kept their car from high school. I kept mine a 1969 Firebird Convertable, all original and needing a complete rebuild for the last 25 + years)

Good luck
Avn-Tech
 

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As long as the suspension, steering assembly and the differential are in good condition it should be fine.

My only problem with your conversion is that you're placing a Warp9 on a car that originally had less than 100HP in it's engine.

This means the Warp 9 at high power could easily destroy your differential.

I would be very careful about accelerating in that car especially because you'll be adding a lot of weight with the lead batteries meaning more stress on the differential.

I myself would limit the maximum amperage on the motor controller to a conservative amount, otherwise you could ruin the vehicle.
It all depends on what controller you want to use.

Grassroots couple the warp9 to different controllers for different output.
eg:
Similar in power to a four cylinder gas vehicle
War P 9" Motor $ 1,670.00
Logi144AFX 750amp Controller $1,345.00



Similar in power to a small block eight cylinder gas vehicle.
War P 9" Motor $ 1,670.00
Z1K-HV Controller $ 2,550.00


So unless your planning on running a Zilla at 144V I think you’ll be OK.
 

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I am about to buy the motor and controller for a Triumph Spitfire conversion. At first I had planned on using the transmission, but after multiple Spitfire forum members suggested I go with direct drive, I started looking into it. The more moving parts I can remove the better!

I haven't done to much with differentials and gearing, etc. So, I'm curious how to calculate what the top speed of the Spitfire would be. I suppose I'll need to know the top RPM of the TransWarP 9" as well. The spec graphs go up to 5,000 RPM. Is that the safety limit for these things?

Sorry for jumping on this thread, but I'll be facing the same issues with the Spitfire. (Including the angry purists!)

-D
 

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very interesting... i am starting a triumph spitfire conversion as well... why would you go with a direct drive for a vehicle like this?

also: @5000 Motor RPM (limited by your controller to avoid blowing your motor), with the diff being a 3.89:1, thats 1285 RPM at the tire, and with a tire circumference of about 70 inches (i think thats about what a 175/75 r13 tire is) so thats about 90000 inches per minute, or about 85 mph. I think...
 

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My main reason for removing the transmission is to get rid of as much moving parts as possible. My transmission is 44 years old, and a high torque motor may just kill it. All of the spinning weight and dead weight of the tranny will only slow it down. I suppose I'm curious as to a good reason to keep the transmission. Will my performance suffer with only one gear? There is a lot about motors I don't know.

If this is being debated elsewhere, please feel free to just send me a link so I can read the pros and cons.

Thanks!
 

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i have two reasons for wanting to keep it:

1. reverse: Instead of dealing with electronic reverse, you can just shift it into reverse no problem

2. efficiency: Ive been doing some simulations on the EV calculator (just google it), and with no transmission, it would be like running in 4th gear all the time. According to the calculator with my specs for motor and controller and all that, i go from about a 55 mile range at 40mph in 2nd gear to a 41 mile range at 40mph in 4th gear. This numbers might be a bit high, but from what ive seen, you almost always have less range using higher gears.

also: with a transmission i believe you can get away with a smaller motor and thus less cost.
 

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Hang in there, rfengineers! I'm in the process of converting a 1974 Lotus Elite, and am happy that it will take a few weeks to get my Warp9 and adapter because there's so much work to do to the car. And yes, that includes designing and installing a new wiring system...the existing one has been "repaired" by too many hacks. Good luck.
 

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hmm interesting... i am playing around with the calculator a bit more, and i've found that the Warp 9 doesnt have the same large decrease of range with different gears. In fact, it is only the 9" ADC (FB4001) that has that problem...

I wonder if it has something to do with the motor itself or perhaps a typo in the motor specs.
 
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