My Blue Max EV Conversion Project

[GoinManta]

Since I put the last post in the wrong part of the forum, I would correct that and put it here where others can actually see it.

Anyone following my EV research and trials and tribulations knows I have been looking at doing an Opel EV for a while. I at first was going to do the Blue Max I had.. but had "almost" decided against it. I was going to do my already restored 4 door Kadett.. but then said never mind to that.. Then almost traded for a GT.. then decided against it and went back to the Manta.

I kept coming up with about the same basic range, and such on all three cars. So I decided I will go with the Blue Max. Just not with the Blue Max interior.. So, by the end of the month (April 08) I will be starting on my Blue Max EV. Starting with stripping the car down and figuring a way to safely remove the vinyl top.

In the meantime, I know others have contemplated and asked for info on doing a EV Conversion, so I will post my contacts, insights, experiences, and screw-ups ( Although I am sure everything will go smoothly and there won't be any though.. ) here.

All I know is that my motor will be ordered within the month and the project will get started shortly there after.

OK.. lets start with the cars.. ( I will focus on my Manta for the most part, if I have anything to add for GT Owners I will mention it too )

Weights :

Opel GT -From GM and assorted magazines

1969 1.1L GT 4-speed, curb weight 1863 - 1881 lbs

1969 1.9L GT 4-speed, curb weight 2070 - 2109 lb

Opel Manta (My project)

1972 1.9L Curb weight : 2232

Approximate weight of:

1.9L Motor : 275 lbs (bare motor)

Motor Accessories : +/- 45 lbs
(Manifolds, Alternator, Carb, Starter, etc.. )

Manual Transmission : 65 lbs

Automatic Transmission : 115 lbs
(Manual states add 50 lbs for Auto)

Weight of exhaust : +/- 20 lbs

Weight of gas tank/metal lines/filler neck : +/- 10 lbs

Weight of radiator and hoses : 10 lbs

Weight of GT headlight buckets & assembly w/ cables, etc.. : 25 lbs

.................

Transmissions

Opel 4 speed Manual - 3.428 / 2.156 / 1.366 / 1.00

TH-180 3 speed Automatic - 2.40 / 1.47 / 1.00

S-10 5 Speed Transmissions
(Much easier to swap to now that you won’t have an Opel motor, and kits are out there for mating to this transmission pretty inexpensively.)

1985 Minivan : 4.3L : 3.50 / 2.14 / 1.39 / 1.00 / 0.73
1984-86 Chevette: 1.6D : 3.76 / 2.37 / 1.49 / 1.00 / 0.86
1985-86 S10 : 2.5L & 2.8L : 3.76 / 2.18 / 1.42 / 1.00 / 0.72
1982-1984 S10 : Most : 4.03 / 2.37 / 1.49 / 1.00 / 0.86

Personally if you are to go the S10 route, go for the 85-86 S10 as the 0.72 5th gear will give you a better top speed.

.................

Rear Ends:

Std Opel Rear Dif Gear - 3.44
Optional GT (Kadett) - 3.18 / 3.67
Optional Manta Rallye - 3.67

For top end speed (especially lower voltage projects (Under 96 V) go with the 3.18 and the Chevy S-10 tranny. The lower the ratio the higher the top end. The thing to remember is the Electric motor has a ton of torque.. and no problem turning the higher gear ratios (Or is it lower.. I always get that backwards - either way the lower numbers) What an electric motor lacks is RPM (Depending on Battery Pack< I will get to that later). You can get some that want to go into the 6000 range, but they are happiest in the 3000 range. Also lower the RPM range, the less power the motor uses.

...........

First things to consider..

The VERY first thing to consider is budget.. There are a few distinctive things you can and can not do based on budget.

A base budget of $3000-$5000 gets you a 72-96V system, running DC power.

Good system for around town, but not long commutes on the interstate.

Pro: Simple to install and Inexpensive, weight is under the GVWR and handles pretty much like it always did. Some minor amount of spring improvement maybe needed.

Con: Not super fast (No worse than 1.9L), 60-65 MPH top speed and a range under 30 miles.

A mid-range budget of $5000-$9000 a DC system in the 144V range.

This option is good for those going on the highways to work regularly.. etc..

Pro: Also simple to install and relatively inexpensive.. , A fast as the ICE Cars on the road.

Con: about 75 MPH top speed and a range under 40 miles. Car is going to be really heavy.

A high budget.. $10,000-$20,000 a DC OR AC system..

This is a car like more modern EVs, with AC you get better power, and regenerative braking power. Not something easily done on a DC System.

Pro: On a DC System, your probably still looking at a 144V system, but you can upgrade your batteries to Li-Ion or Ni-MH dropping your weight back down under the GVWR of your Opel, and the cars handling will improve, as will the range, etc.. Also batteries will last almost double the Lead Acid ones.

Con: If your doing a AC system.. your car will still be bloated and heavy, but it will be able to regenerate power from braking, and have more power. Your probably looking at a Lead Battery 240V system.

Money is no object – AC System

This is a fast and nimble home made version of the Tesla Roadster.

Pro: Fast as a Porsche, Range over 100 miles, Durable 100,000 mile drivetrain.

Con: Exotic batteries are expensive.. and with the technology changing every day, you maybe out dated quickly. Also parts are harder to find and if a problem arises, expensive to repair.

………………

So you have a budget..

At first I thought the first decision I would have to make was the batteries. After all my research I found that wasn't the case. The overall performance is dictated by the Motor selection, that is dictated on transmission (or lack there of) choice. All of which as noted above is dictated by budget. To a point.. more on that later as well.

Anyway, I am going with something between the basic and mid-range. High end Sealed Lead Acid batteries and High End DC motor, mated to mid-range and budget components. To save weight and money I am going with a 96V system.

The great thing about this approach is when new battery technology emerges, I can upgrade to better batteries, bigger pack, new controller and leave everything else the same. Because the motor I selected operates in a range of 96V to 194V. So I have room to improve later.

...........

So you have the budget figured out.. now the motor.

There are a few different manufacturers of motors for EV Conversion, the biggest being D&D, Advanced DC, and NetGain. Netgain being the motor of choice for most EV’ers. Their motors tend to be better built, heavier duty, and they have a larger selection of motors in the higher HP and Torque range. Those that disagree that NetGain is the best, tend to be the vendors that don’t sell NetGain at all. Ask the companies that sell both or all three and its NetGain hands down. Same holds true for the hobbists that are making EVs.

So that said, before you can select a motor you have to select a transmission.. because some motors can do some things and some can do others. While some can do it all.

Direct Drive..

Some companies offer direct drive kits, using ADC motors. But from what I have heard they will be sluggish and run into overheating and reliability problems if you are hard on the car at all. If your building something for just around the neighborhood then maybe..

With the (http://www.go-ev.com) NetGain Transwarp 9, Transwarp 11, and Transwarp 13 motors you can get them with a short Turbo400 shaft and simply make a driveshaft and bolt them in. In theory this is easy and great.. in the real world I was told unless your under 2500 lbs, this is not a good option, that is unless your looking at drag racing your Opel.

The reason is they get hot, certain stresses of that design can lock up the motor if your on a hill at a stop light, etc.... I am not sure of all the "ins and outs" but a talk with the manufacturer of the motors pretty much convinced me that if I want a reliable setup, without having to worry about any issues or breakdowns then I shouldn’t go direct drive.

Now they did say it can be done and would be great. The basic gist of it was that in my application and with the hills in my area, it wouldn’t be prudent. That said, if you don’t have any hills that you have to stop on, say in Florida, Kansas, etc.. then it maybe the perfect option for you.

Automatics

Depending on who you talk to.. (A LOT OF that in the EV world I found out.. more so than the Opel world by a ton..) YOU either can not do a Automatic, its useless to do an automatic, or its fine if your willing to lose a bit of range, power and use a little ingenuity.

Looking at our little bullet proof piece of technology.. Believe it or not the TH180 is probably one of the best choices for a Automatic EV. Small lock up torque converter so the loss isn’t as bad as it could be with say a 700R4 or TH350 and we all know how bullet proof they can be.

The one problem with designing an EV with an automatic is you have to "Idle" the motor to keep the torque converter running and requires a higher torque motor. Not to hard to figure out how to do that.. but its an additional loss of power and range. BTW.. by higher torque motor, it basically means a NetGain motor. The guys that sell ADC and D&D are by far the ones that recommend highly against an automatic.. which kind of tells you something.

Positive side is using the torque converter and a heavier motor means this part of your drive train should last a long time as the stress is greatly reduced.

Manual Transmissions:

By far the best and most popular choice, that said there is areason most Opel owners want to ditch the 4 speed for a 5 speed.

First off as weak as the syncros on the Opel 4 speed are, I would highly recommend replacing the transmission with a S10 transmission. ON top of reliability, the overdrive gear, and such an added benefit is that conversion kits are available for motor in a number of places.

Some like this one: Adaptor Plate, Chev S-10 & other GM to 9" ADC

You will reuse the clutch.. which means you will lose some power and since you can leave your EV in one gear most the time its not necessary.

Others like this one:

JC's EV Division - Services and are available through http://www.evamerica.com

Will make it clutchless and you will have to double clutch shift. But it saves weight on the drive train, and gives you more power and range to a point.

…………..

Since the Blue Max is an Automatic.. and I rather keep the Automatic console, etc.. and its what I have anyway. Its what I am going with.

Since I am going with an automatic.. My motor choice is a Transwarp 9, the largest 9 inch motor available. Its also one of only 2 or 3 that mentions mounting to a Automatic as not voiding warranty. The others being the Transwarp 11 and Transwarp 13..

Well.. now that we got that figured out.. Lets talk Batteries..

[OpelGT-de]

fyi,

see this

http://www.elektroporsche.de/presse/op_1205.pdf

Grüner Flitzer: Sakrileg unter der Haube - Porsche brettert mit E-Motor - Auto - SPIEGEL ONLINE - Nachrichten

elektroporsche.de


Porsche conversation.

The car is suitable for everyday use and the modification costs were close to your estimate

[GoinManta]

Originally Posted by OpelGT-de fyi, see this http://www.elektroporsche.de/presse/op_1205.pdf Grüner Flitzer: Sakrileg unter der Haube - Porsche brettert mit E-Motor - Auto - SPIEGEL ONLINE - Nachrichten elektroporsche.de Porsche conversation. The car is suitable for everyday use and the modification costs were close to your estimate

You will even find if you look online a number of EV conversion businesses showing a 959 Porsche AC EV conversion for $65,000.. (add extra for Li-Ion batteries.. ) Not sure if the companies are all in on it, or if its one guy having them advertise his car.. But for $65,000 its not a bad deal.. compared to $90,000 for a Tesla.

I am writing up the battery article now.. but it's not easy to write. Because as much differences EV'ers have over transmissions and motors, the real "debate" lies in the batteries. That said there is equally as little information on some other apects of the batteries too, especially new sealed lead batteries.. but I digress..

Charles

[tomking]

It will be interesting to see this take shape. But a question, You said:
This is a car like more modern EVs, with AC you get better power, and regenerative braking power. Not something easily done on a DC System.
Why isnt regen braking easy with a DC system? Did you mean braking recharging not easy with DC system? Isnt regen braking easy with a DC system with just shunt resistors?

[GoinManta]

As for regenative breaking. I won't claim to be an expert. I decided against it early so I haven't researched it much. BTW, If I am wrong in any of my posts anyone feel free to correct me. Most of my information comes from different vendors, and manufacturers and EV'ers themselves. Just like the Opel world there are differences of opinon and mis-information abounds.. So take what I say for what it is, raw research that I have collected and consolidated to what I think is fairly accurate. Then I based my build on this information. I could be wrong on some of my info, or approach.. I wont know until I am done.

As for regenative braking..

From what I was told by a few people is the problem isn't so much doing it.. its the nature of the DC motors. They run hot and need better cooling. Netgain as even developed a forced air attachment for thier Wrap 9 motor to help with this.

The real issue as far as I am concerned comes down to a few factors.

1) DC controllers that have regen capablility are newer and not as bullet proof.

2) The controllers are more expensive as well

3) Extra wear on the motor (The motor works in both directions with no "down time")

4) Won't work well on a Automatic.. (Torque convertor anyone?)

All the wear and tear and cost of adding regenative braking adds about 5-8% range.

Since I am limiting batteries on my car for wieght, my range will be about 30 miles. I wil be putting about 16 miles a day on the car in regular use. So I dont need the extra 2-3 miles I will get, so the cost of adding more complexity into the system, and wear and tear on the system isn't worth the cost.

Why modern manufacturer EVs are going AC is simple.

1) As far as I can deduce AC is the better system.. but it runs better as a high voltage system.

2) Regen is more effective in an AC motor due to the nature of AC Power to go both ways.

3) The motors are virtually maintence free other than the shaft bearings.

4) Higher voltage packs are now available in lightwieght Li-Ion and Ni-MH batteries..

5) They run at higher voltages and are they inherently more efficient because of it.

6) The AC motors are also more responsive

So thats why manufacturers are using them.

Why DC is the choice for a hobbyist conversion..

The very simple answer is the very first thing you had to decide when doing a conversion.. Budget.

Higher Voltage = larger or custom battery packs = $10,000-$30,000

That alone puts AC out of most budgets. Now AC can be done with Lead, but your talking a lot of battery wieght even with smaller amp hour batteries.. and even then you would want to use high end Lead batteries. Which would still cost about $5000.

This gets back to batteries selections and pros and cons.. which I havent finished writing.. But you get the idea.

Other costs and considerations for a hobbyist doing AC. Motors specifically built for AC use are not readily available yet and what there is is expensive.. usually double or triple the cost of a comparable DC motor.

As for controllers, the same holds true.. the technology for the hobbyist is also not as readily available and is much more expensive.

As you go up the Voltage level, the more custom and expensive the components are. The base componenets for a 72-96V system are readily availabe and fairly inexpensive. Go to 108-144V and the parts are more expensive and selection of avialable parts starts getting thinner. Go over 192V and the parts get even more expensive.

If you can afford a 192V system ( The limit for most DC motors ) the power and performance of a Siemens AC motor vs a Netgain Transwarp 11, would be about the same.

I was told it's simple.. it takes X amount of watts to drive down the road, physics doesnt car if its DC or AC or what voltage. So DC vs AC wont affect range, or power. Thats in the design of the motor you select and the battery pack size and voltage. That said, because you can run the AC systems in some very high voltage ranges I have seen as high as 400V and more. They can be more effiecient than the DC systems.

The last thing to mention is how batteries affect range. Just because you add twice the batteries does NOT mean you get twice the range. Now this is true and false at the same time..

This is an example, not real calculations..

If you took a 100 lb Lead Acid Battery with 100 amps and went 10 miles.

If you doubled the lead batteries you would probably get you 14-15 miles for your 200 lbs.

If you instead installed a 100lb Li-Ion battery with 200 amps, then you would go 20 miles.

For the record, those numbers are off the top of my head not real numbers, but they give you an idea of why AC systems go further. Its because the guy building the AC system has more money, and thus can afford better and lighter battery packs.

A real example would be my project battery pack is a 96V at 166ah thats 8 batteries at 103lbs or 824lbs for the pack. Which is 15936 Wh of juice.

I could have gone with a 144v at 100ah thats 12 batteries at 68lbs or 816 lbs for the pack. Which is 14400 Wh.

I will let you in on something.. the 100ah batteries cost about 80% the cost of the 166ah batteries.. and since I need four more of them, they will cost more as a pack for less Wh. Not to mention the extra wieght and issues of having 4 more batteries.

Then add to that the cost of the 144V components verse the 96V would add about $2000 more to the cost of the project. But would only marginally affect the project. The 144V pack would give me more "HP" and high end speed, and the little more range given by the higher voltage is offset by the less Wh in the battery pack.

Due to the 3 main reasons Budget, Budget, Budget.... my system will be a 96V DC system without regenative braking..

Now to select the batteries.. Wet, AGM, VRSLA, SLA, FireFly, NiMH, Li-ON, Li-S4, which ones are best.. ? 6V, 8V, 12V or 24V batteries to build the battery pack? Lets say I may not know if I am right until I am done and can test what I selected. The batteries I selected have been around a few years as UPS batteries, and should be perfect.. so far havent found a sole that has used them. Hopefully my information is good and they will work well. I will go into what batteries I am using later.

[tomking]

The auto tranny would negate regen braking

[oldopelguy]

Originally Posted by GoinManta (Torque convertor anyone?)

Any particular reason for running a torque converter at all? With nearly full torque available from 0rpm with the electric motor you don't really need the torque multiplication, and the slippage and heat would both be bad things for battery life. Lots of race cars running around with a stub shaft of sorts direct coupling the engine into the trans without the torque converter, I would see if a local transmission shop thinks the Opel auto can handle it or not.

[GoinManta]

The issue with wanting to run an Auto is just simply a matter of ease of modification..

The reason I believe I have to keep the torque convertor is so I have the pressure to do the shifting.. doesnt the transmission rely on the pressure of the ATF to operate?

Charles

[blancojp]

In order to maximize the available components and reduce weight, I believe you should be looking into a CVT unit instead of using a regular car type transmission.

As to the power supply, I believe a transwarp motor at 96Vdc requires 180A per hour to maintain HP rating. So when you take off, you will need three times that amount to break inhertia on the motor and induce rotation. This means everytime you take off from a stopped position, a good chunk of your power supply gets utilized.

I believe your project has merit so continue the good work!

[GoinManta]

Originally Posted by blancojp In order to maximize the available components and reduce weight, I believe you should be looking into a CVT unit instead of using a regular car type transmission.

Dont disagree.. but that said.. this falls into the first selection issue. Budget. I don't know of a CVT transmissions in a RWD configuration thats available, most are in FWD. Even if I did, I doubt they would be realitively cheap at all.

If I were to ditch the Auto, I would go to a S-10 manual. Again.. for budget reasons. It would be inexpensive and has a history of being a standard transmission used on EVs.. and of being used in Opels. So I know it would fit fairly well, conversion parts readily availble, and inexpensive. On the plus side if I went to a T5 tranny, I could go to a cheaper main motor. To be honest its still a possiblity. But I think I rather have the Automatic.. believe it or not I want to keep the automatic, mainly to keep the interior looking stock with the automatic shifter. Silly I know. I may still get the S10 tranny and see how it fits and looks. Since they are fairly cheap at my local pick-a-part.

Originally Posted by blancojp As to the power supply, I believe a transwarp motor at 96Vdc requires 180A per hour to maintain HP rating. So when you take off, you will need three times that amount to break inhertia on the motor and induce rotation. This means everytime you take off from a stopped position, a good chunk of your power supply gets utilized. I believe your project has merit so continue the good work!

Thats about right.. My pack will have a higher peak rating than 166a.. thats the 20 amp hour rating. The 1 hour rating is 91.8 amp. Which means roughly I have 51% of that or about 30 minutes of continuous run time. Depending on my speed, the amount of stop and go, time I spend coasting or going downhill vs time I go up hill, etc etc etc... I should get about 45 miles in a standard city cycle, or if I got on the interstate and ran at top speed of 65 mph, about 31 miles.

Either way I attached the battery selection I have.

If any more of our electrical engineer types that arent afraid of math want to critic it, feel free. Like to get your opinon of the battery selection.

I also included the alternate battery I was thinking of going with, and may have to go with depending on budget if the price of the first battery selection keeps going up.

[Aardvaark]

This is an interesting project. I had electric car experience with slot cars
as a kid scratch building them, but this is way more of a challenge. Will the extra weight necessitate beefier brakes do you recon?

[GoinManta]

Originally Posted by tomking The auto tranny would negate regen braking

Which is why amoung a few other reasons the regen braking got crossed off the list early..

[jtb]

Awesome post, Charles, very interesting reading.

It is my understanding that the AC motors have regen capabilities by their nature (think about your alternators, guys). But the controllers can be really expensive for AC. There is a Porsche 928 AC conversion in my neck of the woods, but the cost of his conversion is "don't even ask!". Al Godfrey's 1978 Porsche 928

I look forward to reading more, keep it coming!!

Cheers,

jtb

[opelwasp]

Now Charles, does this mean you will be forever altering one of the last 3 Manta Blue Max's? I hope not. Try to keep this project reversible.

[GoinManta]

Originally Posted by jtb It is my understanding that the AC motors have regen capabilities by their nature (think about your alternators, guys). But the controllers can be really expensive for AC.

That would be very true.. which is why I again say budget is the number 1 thing to consder on a EV Conversion.

Budget dictates DC vs AC, Range, Battery type, etc.. etc.. etc.. All which of course dictate the other.

But the biggest thing is the budget. If you only have $5000 then a low budget DC is your ONLY choice..

Here is what I have come to realize.. in very general terms..

$5,000 or so - Base model 72-96V DC (Lead Acid)

$5,000-$10,000 - 96-144V Mid range DC (Sealed Lead Acid)

$10,000 - $15,000 144-192V High End DC (W/ possibly somewhat exotic batteries maybe regen) or low end AC with Lead.

$15,000 - $20,000 - Thats when you can start talking high voltage AC with exotic batteries..

Anything over $20,000 your talking AC, lots of Li-Ion batteries, Regen braking, etc. etc.. etc..

So there is no debating that thier are a ton of options, and various opinons.. Just as there is no debating.. you can only get certain things and certain setup for a certain amount of money.

Thus.. when deciding to do a EV, budget is the first thing you have to consider. Of course, the older this post, the larger the chance there will be whats available for what amount of money will change as well.

Charles

[GoinManta]

Originally Posted by opelwasp Now Charles, does this mean you will be forever altering one of the last 3 Manta Blue Max's? I hope not. Try to keep this project reversible.

Yes.. that said Mother Nature had more to do with it than me.

Also when you consider I had it for sale as a Blue Max with all the Blue Max bits I collected for a few months with no takers, then just with the metal to restore it, and again no takers, then as a base to start a restoration with.. again no takers. It came to what I originally said a few months if not years ago.

It maybe a Blue Max.. but in reality its a solid $800 Manta.. nothing more nothing less. Too much rust and work needed for anyone to restore unless really committed, and to be restored as a factory original car.. almost impossible.

It would be too expensive for me to find another early Manta to replace this one to do a EV project on. Just to sell this one for a loss, to someone that MIGHT restore it to a Blue Max and then buy another restorable early Manta for more money. It just makes no sense.. add to that the rust I have to repair, and the fact I have to remoe the vynil roof to attack the rust, etc. etc.. its not to far gone to modify and play with.. but its too far gone to restore back to a Blue Max.

Now on the plus side, a Blue Max owner in Florida.. is getting all the Blue Max bits and pieces (Seat covers, etc.. ) to restore his to a real Blue Max. Since mine is not going to ever go back to being a real Blue Max.. so all my work collecting the Blue Max parts, and the Blue Max parts from the car will go to good use.

Charles

[GoinManta]

Originally Posted by Aardvaark Will the extra weight necessitate beefier brakes do you recon?

Exactly.. wieght is the a midigating factor.

For the same wieght (Say under my target of 2600-2900 lbs)

Lower budget = heavier parts = lower range

Higher budget = lighter parts = higher range

Mix any of those..

But as you noted.. say you go even lower on the budget with cheaper batteries.. guess what.. ?

Cheaper batteries = heavier wieght = reinforced brakes and suspension

Which of course means more money to reinforce brakes and suspension..

Thus the batteries I choosed.

I do plan on rear disc brakes (ala my tried and true Isuzu Disc brake project) and 75' front brakes and station wagon springs. If I stay under 2800 lbs that should be enough. If I go over the GVWR of the Opel you have to beef up suspension and brakes over those simple modifications.

Charles

[blancojp]

I believe your best best is to minimize the weight of the vehicle and try to remove the unwanted mechanicals. An auto transmission would be an extra weight which will only serve you to eat up your power supply.

We had a project like this at RR where we designed a vehicle to be used by tourists in Barcelona. We decided to modify an existing vehicle with a 5-sp tranny but we killed the range due to un-necessary power usage. We then converted the same vehicle using a modified series 92 torque converter from Comet industries and the results were surprizing. By installing the motor and torque converter over the differential, we gained 22% in speed and 38% longer range with the same 96V power plant.

In your case, you are removing the engine (300Lbs approx.) and adding over 500Lbs in batteries and framing. Since you are using an automatic with a torque converter, the motor will need to spin to over 800rpm before you transfer any power to the drive shaft. You will also have an insertion loss due to the other internal transmission peripherals you need to move as well. And last but not least, you will have an insertion loss created by the controller which also requires power to operate. Overall efficiency will be very low and your range will be minute in comparison to the calculated values.

You also have other peripheral devices which you need to power, like lights and so on. Normally you would use what we call a house battery bank to power all of these. This would add an extra 80Lbs to your vehicle unless you drive these from the 12Vdc aux port on the controller; which will eat up your supply even faster.

Not being Johnny Raincloud here, your project has merit but in an electric vehicle gasoline mechanical components are not always the wise parts to use.

[GoinManta]

Originally Posted by blancojp I believe your best best is to minimize the weight of the vehicle and try to remove the unwanted mechanicals. An auto transmission would be an extra weight which will only serve you to eat up your power supply.

I agree... but when you go back to the first choice, budget, the auto fits the budget for now. That said the current version of the project won't need a ton of range.. under 20 miles will be fine. My new job will be under 3 miles away so the limitations of the auto transmission aren't a terrible hinderance, and I am just curious as to what the end result will be. So thats why I am sticking with it for now.. If it proves to be a terrible choice, then I will swap it for a S-10 5 speed. Probably in a clutchless setup. The other option maybe to see if I can convert a VW rear end into the Manta, and then go with a true clutchless VW rear transmission.

Originally Posted by blancojp You also have other peripheral devices which you need to power, like lights and so on. Normally you would use what we call a house battery bank to power all of these. This would add an extra 80Lbs to your vehicle unless you drive these from the 12Vdc aux port on the controller; which will eat up your supply even faster.

Better than that.. Transwarp 9 motors are dual shaft.. meaning there is a shaft end on both ends.

I plan on running a Geo Metro Alternator for the 12V, buffered through a small 12V 30ah battery and a Puegeot Diesel Vacuum Pump for the brakes. Drag on the motor should have minimal affect on range or power output. Overall weight & cost will be much less than a 12V DC/DC convertor and/or larger battery/charger and electric vaccum pump.

The great thing about starting on the low end with the transmisson I have, lead acid batteries and a 96V system, but with a high end motor (The upper range of the Transwarp 9 is 192V with the right controller). Is that I can remove the motor and change the transmission, upgrade the batteries or the controller or both as a budget for upgrades presents itself. So I can go to 144V, or the 5 speed, or a CVT or some other transmission. To lighten the car, improve range, etc. etc..

But as I have mentioned from the start, the budget is the driving force which then dictates the other choices. So while limited in range, power, etc.. with the first generation of my project, I can still upgrade later on. That's why after the second most important choice after budget is the motor.

Charles

[blancojp]

If you are going to use a transwarp motor, get the one that has the built in drive shaft end and tie it directly to the rear end via the Opel drive shaft. Place the motor where the transmission goes and now you have a light solution which if you do the math, top speed should be far greater than 70mph.

Electric motors of this type can accellerate at the 100HP rate for a few seconds, which should allow you to take off quite nicely. If it is coupled to the rear end, you gain regen when the controller is at idle stage so you are able to charge your batteries when going down hill or coasting. Just take the example of a jet engine, the starter is enabled to spin the rotor and when the engine starts, the starter becomes the generator which charges the system.

The second point is the Geo alternator requires a minimum RPM for power generation. In your case, the alternator will only work when you are moving so your battery might not get any charge to speak off. The vacuum pump can be easily replaced by a Wilwood manual master cylinder with individual front and rear circuits. The complete brake pedal assembly is about $275 and works just as well as what you are proposing. You don't really need to do anything to upgrade the brakes but if you do, use the Geo Metro front brake upgrade I posted some time ago and upgrade the rear to a 3/4" wheel cylinder. That will stop the car 20% better than the stock unit while reducing front weight.

I can help you with the controller since I designed several of them in the past for a multitude of different HP motors. So when you get to that stage, let me know and I can look for schematics which are suited for the electric motor selected. The controller also has a braking system which only applies to the wheels driven if you connect the motor directly to the driven wheels.

Hope this helps you.

[GTJIM]

You can eliminate the torque convertor by using a sleeve connected to the crankshaft to operate the oil pump and seal the ATF into the auto trans.
You do not need a clutch or any other method of de-coupling the electric motor since its speed is fully controllable - down to zero revs - and peak torque is available right from 1 rpm. The auto would still shift (and have reverse available) to give more gearing to help the electric motor accelerate the car.

[GoinManta]

Thats awesome !! Do you know where I could get a sleeve pre-made for a TH180.. That would make the automatic almost more effiecent than the manual. There wouldnt be the shifting lag.. Not to mention removing the wieght and issue of the torque convertor.

As for direct coupling the motor to rear end.. that was my initial concept, but told by the guys at Netgain that that could overheat the motor in a daily driver. The direct coupling option is more for drag racers where its not as critical. One of the things that is causing the concern for overheating.. is in the way to Midlothian, there is an about 100 foot hill at about a 4% grade for 1/4 mile or so. At the top of the hill is the stop light I have to take to get into my neighborhood. So the concern is the motor will heat going up the hill, and as I go from a dead stop..

As for the alternator, the plan was to use it to charge a small 12V battery, something about half the size of the standard Opel battery and use that for a small radio and lights and heater.

The real issue I was told was the 12V DC/DC Convertor put an unequal drag on the battery pack and it was best for the battery pack life and balance to run a completely seperate system. Also it goes back to budget. An alternator and battery is much cheaper than a 12v DC/DC Convertor, same holds true with the Vaccum Pump. Used Peugoet Vacuum pump, cost me $45. THe electric versions are over $300 and redesigning the brakes to go to a manual brake would cost even more, not only that the car will be heavy, and I think I really need the brake boost.

My plans for the brakes are simple..

Opel Commodore "B" Master Cylinder with a 75' Opel Manta Booster
75 Manta A brakes in the front
1985 Isuzu Impulse brakes for the rear

That should help with the heavy rear end of the battery pack.

So... that all said.

How much would a home built controller cost?

Could it be made to be programmable or adjustable to go from 96V to 144V or so.. ?

Regen ?

Whats your thoughts on the overheating issue of the Transwarp? Over concern by the manufacturer?

I will say this.. these are the only "DEFINATE" things I am 100% on right now.

1) The car will be the 73 Manta
2) The motor will be a Transwarp 9
3) Wieght will be right under or around 3000lbs
4) Batteries will be Sealed Lead Acid.. and somewhere between the Powersonic PG-12V150-FR and the PS-121000 The higher amp perfeered, the lower amp due to budget. There are 120 and 140ah Powersonic versions that could also be used..

I am open to change plans.. as long as the budget stays within $5000 for the conversion. I dont have much room to go over that.. as I still have interior and exterior body work and paint to consider.

Charles

[vikesman101]

Charles

I am following this as best I can... and not being a jeanous I am doing my best to keep up. My mind contimplates to other concepts and wonders if they help at all in your quest. A gas powered golf cart uses a small engine that starts when you step on the gas, the drives a generator to refill the battery. Could you use a small perhaps diesel engine to accomplish more or less the same thing? Or are you trying to stay 100% electric? If you want a strictly EV then my second thought is also a mute point... locomotive are diesel electric as well and run on a similar design and I have often wondered why the current hybreds don't use that idea.
I only point all this out because I started doing the math, and when you factor in intiall costs and replacement parts (batteries) as well as routine maintance, this does not seem very cost effective. Am I wrong on this? Either way I find this very intresting and will folow your progress closely.
Good Luck
Tom

[opelgt73]

Originally Posted by GoinManta Thats awesome !! Do you know where I could get a sleeve pre-made for a TH180.. That would make the automatic almost more effiecent than the manual. There wouldnt be the shifting lag.. Not to mention removing the wieght and issue of the torque convertor.

I can't for the life of me figure out why you would want to use an Auto transmission on an EV car. There is no need for it. Even without the torque converter it robs power and is still heavier. You don't need all those gear ratios in an EV, most EV folks will tell you that they typically put their (manual) car in 2nd or 3rd and never touch it again.

Originally Posted by GoinManta As for direct coupling the motor to rear end.. that was my initial concept, but told by the guys at Netgain that that could overheat the motor in a daily driver. The direct coupling option is more for drag racers where its not as critical.

I don't understand this either. If the motor to final drive ratio is the same (as say a manual in 2nd gear) then why would their be more ware on the motor? The problem is you would need to swap out the rear diff with the proper ratio.

Originally Posted by GoinManta As for the alternator, the plan was to use it to charge a small 12V battery, something about half the size of the standard Opel battery and use that for a small radio and lights and heater. The real issue I was told was the 12V DC/DC Converter put an unequal drag on the battery pack and it was best for the battery pack life and balance to run a completely separate system.

Can you post a link where this is being explained? This seems to be opposite of what I would expect. I find it hard to believe that 1). Main Battery->EV drive motor->Belt->Alternator->separate accessory battery pack is more efficient than a switch mode DC/DC converter or that 2). A DC/DC converter causes unequal drag on the battery pack. If anything I would expect it to cause a linear drag on the battery pack whereas the drive motor (stopping and starting) would cause an unequal load.

[GoinManta]

Originally Posted by opelgt73 I can't for the life of me figure out why you would want to use an Auto transmission on an EV car. There is no need for it. Even without the torque converter it robs power and is still heavier. You don't need all those gear ratios in an EV, most EV folks will tell you that they typically put their (manual) car in 2nd or 3rd and never touch it again. I don't understand this either. If the motor to final drive ratio is the same (as say a manual in 2nd gear) then why would their be more ware on the motor? The problem is you would need to swap out the rear diff with the proper ratio.

I dont understand it either. But apparently this is where the theoretical world and real world converge.

That said, the reason could be gearing. As you noted most EV'ers stick it in 2nd or 3rd and leave it there. Lets assume that the average 2nd or 3rd gear is 2.2 then the average rear end is say a 3.4, that would be a final ratio of 7.5 or so..

So to get the same effect in a direct drive application would require a rear end in that area.. Which would be why transmissions are still put into EVs as opposed to going direct drive.

As for Automatic vs Manual.. I am not 100% married to the Automatic. But the car came with one, and installing a S-10 transmission would be more cost. Cost for the S-10, fitment, drive shaft, etc. etc..

So the reason to stick with the Automatic is simply one reason only.. Budget.

The advantage of sticking with the TH-180 is that until its all assembled and running, everything is theorehtical, everything that is except the budget. So if I stick with the automatic, and the perfromance, range, etc.. is adversely affected, then the only thing I am out of is the money to make the engine/transmission adapter. Which will be less than the cost of the S-10 transmission.

I can then easily swap over to the S-10 tranny when the budget allows. The Automatic allows me to complete the project within the budget for now.

Originally Posted by opelgt73 Can you post a link where this is being explained? This seems to be opposite of what I would expect. I find it hard to believe that 1). Main Battery->EV drive motor->Belt->Alternator->separate accessory battery pack is more efficient than a switch mode DC/DC converter.

No link.. it may not be more efficent, that said, may only marginally less efficient. Again its a matter of budget. The DC/DC convertor can cost over $300. The alternator cost me $20 at a pick-a-part. That said, it wasnt a Geo Metro one, instead I got an OPEL Alternator off a 1.3L Pontiac Lemans it was equally small, and looks to be fairly light.. not only that its Opel

Originally Posted by opelgt73 2). A DC/DC converter causes unequal drag on the battery pack. If anything I would expect it to cause a linear drag on the battery pack whereas the drive motor (stopping and starting) would cause an unequal load.

I had this explained to me this way.. the battery packs like a equal load taken on them. In the case of a DC/DC convertor it will tend to pull the voltage out of the closest battery in the pack. Causing it to be discharged more than the rest of the pack, meaning it will develop an imbalanced charge to the rest of the pack.

To this point, I am even looking at the fact the UPS batteries I picked show a problem with this on the charging end more so than flooded batteries, they are meant to be at most in groups of 4. So I think I came up with a cheap and yet simple solution to help the batteries get charged more evenly.

A pack of 4 in the front and a pack of 4 in the rear. They are joined together as a 96V pack in operational mode. But when I go to charge I will disconnect the two packs and charge each set with a 48V charger. This has a few advantages. First of all being the fact 2 48V chargers are cheaper than a 96V one. The second the batteries should get charged more equally and faster. Because the charger only has to focus on 4 batteries and balancing the charge of the 4. If I set both chargers at the same final voltage, then the packs should stay in balance as well.

Again its theorhetical.. but I like it due to the fact it would also be cheaper.

Again, if for some reason this doesnt work.. I can easily switch to a 96V charger later.

I am not saying all the things I am doing are the most optimal, efficienct or in some cases may even go against the best design practices. What I am doing is based on wanting to convert my Manta to an EV and within the $5000 budget. Since the motor will cost $1700, and the controller another $1100. That leaves $2200 for everything else. The Battery pack alone will cost at least another $1800 (PG-12V120 FR for example), I truly want to use the PG-12V150V FR batteries.. but they will cost almost $1000 more than the 120 model so using them would put me $600 over budget and I wouldn't have bought a single cable, or tranmssion adaptor, or vaccum pump, or brake component yet... With the 120 model it still only leaves $400 for all that. Which means no matter what unless I find cheaper batteries, or controller I will be over the $5000 budget.

The plus side of the 120 over the 150 is a savings of 23 lbs a battery or almost 200 lbs. Now I am under no illusion, I will be over budget. But I want to keep the EV conversion components to at least meet the budget.

So you see, I have to balance everything against the budget and wieght. I know it would be BEST to go with a 144V system. That adds four batteries, thier cost and wieght, now I can reduce the size of the battery. It would reduce the wieght and the cost to within the budget, but it will cost about $600 more as the components of a 144V system have to be stronger than the 96V, and cost more and are less available. I.E. the chargers, have to be more complex to balance the battery pack, etc.. The end result is I would weigh considerably more, and cost more. Not to mention since I would wiegh more extra modifications to suspension and brakes owuld incur more cost.

Its not that I am not listening to everyones insights and comments, and for the most part I agree with them.. but the budget is the key element I have to consider.

Thus an automatic, along with an alternator and vaccum pump to operate the brakes and accessories.. while not the most efficient options, should save me over $1000 minimum in my project. What I sacrifice for budget is range and power.

Charles