# What is the finished weight of your EV?



## BWA (Mar 14, 2015)

I'm shooting for 1800-1900 pounds.

My doner is 1750 with ICE.

Hoping to pull 500 pounds out of it. Engine, tranny, exhaust system, fuel tank, rad, heater, generator, clutch pedal and cable, rear seat etc.......

New E motor is 90 pounds, leaves me with nearly 500 pounds for batteries and electrics.

Should be doable/close.......


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## stealthE (Jan 31, 2016)

Well that is super light!


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## BWA (Mar 14, 2015)

Light = more range = less battery = less weight = more range......

Gee, if I get down to zero pounds, I can drive forever


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## Caps18 (Jun 8, 2008)

I don't know yet until I get mine on the road. But, I am very curious as to what it is. I know the weight of a lot of different parts, but my guess is well under what other people who have converted an S10 have reported.


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## madderscience (Jun 28, 2008)

My xB had an original curb weight of about 2400lbs and as an EV with 32kwh lithium pack it weights about 3050lbs. If I had gone with a more typically-sized for conversions 16kwh battery (100ah at 156v instead of 100ah at 320v) it would have ended up around 2700lbs. Also, the motor I am using (a solectria AC55) is just as heavy as the 1.5L ICE was, so I didn't lose any weight there. Something like an ADC 9" or HPEV system would have resulted in another 100lbs or so of reduced weight.

With lead acid the rule of thumb used to be you needed 1/3 of the overall weight of the vehicle in batteries, meaning often the car gained 40 to 50% over its original curb weight, and that would give you about a 40 mile range. Case and point my old MR2 conversion which on healthy lead could do 50 to 60 miles, had an original ICE curb weight of 2200lbs, and weighed 3400lbs as converted.

These days with lithium you can build a 50 mile car and keep the curb weight within a couple hundred pounds of the original curb weight.


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## twright (Aug 20, 2013)

My 2000 Ford Escort with a 15 kwh lithium iron phosphate pack weighs 2600 lbs. It's about the same as with the ice engine.


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## rwaudio (May 22, 2008)

1986 Porsche 944, 2950lbs with 16kwh pack. Stock was around 2780lbs.


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## favguy (May 2, 2008)

My Skoda was 860Kg (1892lbs) stock. After conversion with a 27kwh lithium pack it comes in at 1100Kg (2420lbs). So 28% increase in weight in my case.


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## jacksdad (Apr 13, 2015)

My Kit car normally weighs around 600KG with a zetec in it i'm hoping to get around 650Kg; chassis and wheels 400KG and 150kg batteries and 100KG motor & transmission and controllers/bms.


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## Vanquizor (Nov 17, 2009)

My Neon conversion was 2650 or ~150lbs over stock. It was far too heavy, I'm shooting for half that this time around.


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## dougingraham (Jul 26, 2011)

My RX-7 ended up at 2424 lbs, just a hair over 600 lbs on each tire. I didn't weigh it before conversion but the placard indicates 2350 for a penalty of 74 lbs. A full tank of gas was about 100 lbs.

One thing you have to remember is that these older cars are missing things like Airbags and power steering, ABS and I no longer have Air Conditioning. Putting the AC back in could add back in at least a hundred lbs.


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## mototreiber (Jun 10, 2011)

Hi,

My MGB GT was 2381 lbs before conversion, now it is 2160 lbs with a 19 kWh-pack.

greetings from Germany,
Sven
http://mgb-gt-e.jimdo.com/


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## halestorm (Apr 28, 2009)

I have a 1972 Porsche 914. Stock curb weight was 2100-2200 lb. When I first converted it using lead-acid batteries, I weighed in at 3060 lb (I had it weighed at a certified scale). The batteries alone were 1160 lb. My 19kWh Li-Ion pack now weighs 360 lb, so I've shed 800 lb -- that puts me at approx. 2260 lb now, which is about the stock weight. (I didn't have it weighed again, I'm just doing the rough subtraction based on the battery differences alone.)

I have to say, that with li-ion the car drives and handles great; quite noticeably different than when it had lead-acid. It feels like a normal car (only way cooler).


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## galderdi (Nov 17, 2015)

I am in two minds about responding because mine is not a road going EV so please ignore this if you want.

My EV weighs in at 530KG or 1166Lbs without occupants. But it has no real bodywork and will never be registered for driving on public streets so its probably not a good point of reference.


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## EVfun (Mar 14, 2010)

My EV is road licensed and weighs in near 1200 lb. It was 1420 lb. when it had 10 Optimas. I replaced that 400 lb. pack with 195 lb. of Lithium and also changed to off board charging. It is a classic beach buggy based on a shortened Beetle frame and doorless fiberglass body.


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## mizlplix (May 1, 2011)

My 1930 Model A roadster weighs in at 1,900Lbs without myself in the seat.

Full model A frame, hand made body, AC50/powerglide, Ford 8.8, Ford straight axle and 38 130 AH cells.

Miz


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## Sterling2015 (Jun 24, 2015)

EVfun said:


> My EV is road licensed and weighs in near 1200 lb. It was 1420 lb. when it had 10 Optimas. I replaced that 400 lb. pack with 195 lb. of Lithium and also changed to off board charging. It is a classic beach buggy based on a shortened Beetle frame and doorless fiberglass body.


Trying to stay under 2000 lbs - moved post to "*VW Standard Beetle Type I Kit car EV* "
Thanks!


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## EVfun (Mar 14, 2010)

Ooh, full Mendeola suspension front and rear on that VW chassis -- very nice! You will notice the frame runs down the middle of the Beetle chassis, so if you are concerned about safety I would recommend a 6 point cage. Otherwise, they do quite poorly in side impacts. Take a close look at the modifications to the frame, that thing carries the weight of the car. Your ebrake mods are cool, but make sure none of the tunnel modifications start to crack. Buggies sometimes have cracking problems with the stock late model ebrake because of the small openings by it.


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## danh818 (Dec 14, 2011)

My 944 weighs in at 2923lbs with driver and has a 62% rear weight bias with a 25kwh pack, stripped, caged, fiberglass and carbon fiber front end.


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## Sterling2015 (Jun 24, 2015)

moved to build thread VW Standard Bettle Type 1 Kit car EV, thanks!


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## dedlast (Aug 17, 2013)

Sterling, You should start a separate build thread so we can keep up with what you're doing, rather than wading through this thread. 

It looks really good, by the way.

B


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## Sterling2015 (Jun 24, 2015)

Will do and thanks!


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## miscrms (Sep 25, 2013)

BWA said:


> Light = more range = less battery = less weight = more range......
> 
> Gee, if I get down to zero pounds, I can drive forever


To be fair weight is probably more determining of acceleration, CdA is generally going to dominate range/efficiency unless you only drive around town.

That might be the downside to the 3000GT over the eclipse, its quite a bit bigger in cross-section area as I recall?

Rob


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## rob_kr (Apr 8, 2016)

I'm trying to follow here (I'm new to the EV scene), and what I read here makes me think my project won't work so I'm trying to double-check. This thread seems the most likely to get a right answer...

I live in Texas, my commute is 125 miles (one-way), and I'd like an EV to cover that. The gas bills were steep when it was at $2.90 a gallon, it'll get back there before too long, and I want to be ready.

An EV looked really good until I did the weight math for the battery pack. No matter what donor-vehicle I pick, at a range of say 150 miles the curb weight ends up 1.5x to 2x the original car weight (a 1960 VW beetle goes from 1850 lbs to 3850).

That would mean an all-new frame, suspension, brake system etc. That's not a conversion, that's all-new car design. Are donor-car-EV's effectively limited to a 40-50 mile range? How do other people get (way) past this point?

Thanks

RK


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## madderscience (Jun 28, 2008)

@RK You are probably best off waiting a year or two for the 200 mile Chevy Spark EV, 200 mile leaf, or the Tesla model 3. It will be a challenge to build a car with anything close to that range and reliability you need for less than the ~30K price these all will have. 

Also, we generally figure wh/mile and thus range on the highway at around 60mph. If you commute at 80mph on those wide open stretches of highway you have down there, you will need about 40% more battery than the same distance at 60mph, owing to wind drag increasing as the square of speed.

Of course with a 250 mile round trip commute you will still have to charge someplace on the trip. Hopefully a L2 charging station will be available at your place of work, even in the 'worst case' of a 3.3kw station over an 8 hour workday you will get back roughly 100 miles of range, enough to make the round trip with a fair amount of margin. The other option is a L3 charging station at your coffee break spot coming or going.

If you do want to build something, ditch the bug idea. Go for the absolute smallest and most aero donor you can find. That is probably a gen1 honda insight. EV conversions of these are able to do significantly under 200wh/mile. (20kwh for 100 miles) You might then be able to approach 200 miles usable range on 2 nissan leaf packs (48kwh nominal). that is still 1200lbs of battery, so you would have some significant work to do to upgrade suspension, brakes, etc. there are more energy dense battery options that could get the battery weight back down under 1000lbs (tesla cells, LiPo, etc) but way more expensive. For the rest of the drivetrain, HPEV AC system would be best. In terms of component costs now that nissan leaf batteries are the most affordable option for conversions you would be able to gather the parts together for less than 30K but there is still all the engineering and labor you need to put into it, including suspension/brakes work owing to the amount of weight you would be adding for an extreme range conversion. Another challenge with a conversion you are planning on driving 250 miles a day is that L3 (fast) charging options are limited. BUT you can buy L2 chargers (manzanita) with 70 amp capability, which can add back 80 to 100 miles of range per hour, assuming you can find an L2 charging station that supports that much. Maybe your employer would be willing to install, or allow you to install, one.

Dont get me wrong, I am a fan of conversions, but the economics of just buying OTS are quite compelling in this case, unless you really want to do something unique. It sounds like you mainly want a less expensive commute.

I suppose it isn't practical to move closer to where you work?

Good luck.


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## dougingraham (Jul 26, 2011)

rob_kr said:


> An EV looked really good until I did the weight math for the battery pack. No matter what donor-vehicle I pick, at a range of say 150 miles the curb weight ends up 1.5x to 2x the original car weight (a 1960 VW beetle goes from 1850 lbs to 3850).


Hopefully this 125 mile commute is all highway driving at 70 mph. If so what you are looking for is the most aerodynamic car you can find to convert. The first gen Honda insight come to mind. With that as an EV you should be able to get close to 200 Wh/mile so for an 80% pack usage you would need 156 miles of range. That means a battery pack of at least 31.2 kWh. You could do this using two Leaf Battery packs (48 kWh) or a pair of Volt Battery packs at (32 kWh). You could also use about half of the modules out of a Tesla Model S 85 kWh pack. This would give you 42 kWh at a weight of 440 lbs for the modules. The Leaf and Volt batteries are heavier at less capacity than the Tesla modules.

The above assumes you can charge at work. I say that because even with a Tesla you would be hard pressed to make 250 miles without recharging every day. Cold and rainy days with wind would make this impossible without driving too slowly to be practical. With having to replenish at least 32 kWh you would need a charge rate of 3.2 kW for 10 hours, or 4 kW for 8 hours. A 4kW service would be 240 volts at 20 amps so not unreasonable.

What would you save as far as costs go? This is an estimated 62500 miles per year. Cost of electricity if you are paying for all of it would be around $1500 per year assuming 0.12 per kWh and 200 Wh/mile. Cost of gas assuming 30 miles per gallon and $3 per gallon would be $6250 or a savings of $4750 per year.

This is all on the edge of practicality, doable but borderline and it can't be done on the cheap. My own feeling is that you should rethink where you work or live to get back the four hours of your life each day you spend driving.


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## dougingraham (Jul 26, 2011)

Now that I have read Madder's post we say almost the same things. Please do a conversion or buy an OEM EV that will meet your needs. And try to find some way to reduce your driving distance. I like to drive but I can't imagine liking it for 4 hours every day.

Best wishes!


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## rob_kr (Apr 8, 2016)

Thank you both for the insight, and amazing how the two line up. If moving closer etc were an option I'd already be there (I've been doing this for 2 years now), so I'm stuck with the commute.

I looked at the Tesla S, and I'm not seeing that one. It's a $75,000+ car, and I'd get it to 200,000 miles in 3 years. Add 6 sets of expensive tires, shocks etc (Tesla parts are up there), and I'm writing off $100,000 in car in 36 months, so $2,800 per month. Tesla won't even offer a guess if the car will last much beyond 100k, 120k miles, so I'm passing.

When I asked about the new 3-series (and an E-golf and a Bolt), same story just lower numbers. They're pretty much saying it will die in 2 years (120k - 150k miles) and it's $35,000. That's $1,500 just for the car, nice, but still not feasible.

That's where the donor car idea comes in. 

If I can find an older car, the depreciation part of the cost drops dramatically. Spare parts drop, tires drop, the Siemens motor should last a few thousand hours, and all of a sudden the money is not so bad. Plus it makes the project way cooler 


Charging at work is a given/must-have, and it's no issue. The company is happy to sponsor a full-on charging station at 208V, 240V or even 480V 3-phase (as well as a dedicated parking spot ), so that piece is handled. 


The overall vehicle weight is where I get stuck.


The Honda Insight is 1,890 lbs, and let's say the ICE++ removal drops that to 1,400 lbs? At 200 Wh per mile + DOD + 150 mile range + AC (this is Texas) etc, that's a 40kWh battery pack so 900 lbs + Siemens motor + bits&pieces, and all of a sudden the whole thing is 2,700 lbs++. The poor little car would break in half. I'd have to beef up the frame, suspension, brakes etc, add some more batteries to drag all the extras around, and it comes out at 3,000 lbs with a huge bulge in the hood to try and contain all of the batteries.

That's the part I'm not seeing / where I have a blind spot. The lighter the car, the more I'll have to re-engineer the thing to make it hold the weight of the batteries etc.


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## samwichse (Jan 28, 2012)

If you went a little higher-end on the batteries and use half a Tesla pack, you could shave 300 lbs from that total.

The engine swapped with the Siemens motor is probably a wash, as the ICE is feather light. Dropping the IMA motor+battery+controllers+fuel system probably gets you 300 lbs. 

If you can do some aluminum work, the IMA battery and the computers/drive electronics sit in a compartment over the fuel tank (but the tank is separated by the body sheet aluminum).

There's also a storage bin behind the battery that goes to the floor with the spare tire in it.

So you could basically drop the floor on top of the gas tank down to the real bottom of the car and make a more space efficient pan of the spare tire well (someone on the forum did this after their car was rear ended and more than doubled the volume in that area). If you did that, there would be a huge amount of space back there for batteries. 

Since you would be redoing the floor back there anyway you could make it fairly beefy, and the rear springs can be drop-in-replaced with Chevy Aveo springs to increase carrying capacity.

Seems doable, but not easy.


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## dougingraham (Jul 26, 2011)

rob_kr said:


> I looked at the Tesla S, and I'm not seeing that one. It's a $75,000+ car, and I'd get it to 200,000 miles in 3 years. Add 6 sets of expensive tires, shocks etc (Tesla parts are up there), and I'm writing off $100,000 in car in 36 months, so $2,800 per month. Tesla won't even offer a guess if the car will last much beyond 100k, 120k miles, so I'm passing.


There are a few people who have around 200k miles on their Model S. Tesla has an 8 year unlimited miles warranty on the battery and power train. I bought a pre-owned one last December. I have seen no frills 85 kWh cars selling for under $50k. You can put 60k tread life warranty tires on it and if you don't do max accel launches they will last.

What do you think is going to wear out? In the motor I suppose you could wear out the bearings but probably not for 20000 hours which would be 1.2 million miles at 60 mph. The brake pads will probably never need changing the way you are using the car. Probably the only service item might be changing the differential lube. Wheel bearings? Get a car with air suspension. Mine has it and it is great!



rob_kr said:


> If I can find an older car, the depreciation part of the cost drops dramatically. Spare parts drop, tires drop, the Siemens motor should last a few thousand hours, and all of a sudden the money is not so bad. Plus it makes the project way cooler


The Honda Insite conversion I saw used an AC-50 and no transmission. Used a Leaf pack for the battery. His car weighed less than the original with a 120 mile drop dead range. He had plenty of room for another full Leaf pack in the back and it would have had plenty of cargo space still. Using 8 Tesla modules would cut the weight of the batteries considerably. A Leaf pack weighs ~650 lbs, almost half of which is packaging. If you used Tesla modules you get about 5.3 kWh per module. The Tesla modules weigh 55 lbs. 6 Tesla modules would give you 32 kWh at a weight of 330 lbs. 8 modules gives 42 kWh at a weight of 440 lbs.



rob_kr said:


> The Honda Insight is 1,890 lbs, and let's say the ICE++ removal drops that to 1,400 lbs? At 200 Wh per mile + DOD + 150 mile range + AC (this is Texas) etc, that's a 40kWh battery pack so 900 lbs + Siemens motor + bits&pieces, and all of a sudden the whole thing is 2,700 lbs++. The poor little car would break in half. I'd have to beef up the frame, suspension, brakes etc, add some more batteries to drag all the extras around, and it comes out at 3,000 lbs with a huge bulge in the hood to try and contain all of the batteries.


I believe you are underestimating the amount of stuff you are taking out and overestimating the amount of stuff you are putting back in. I took out over 700 lbs on my RX-7. 90 lbs of that was in the exhaust system. The batteries would easily fit in the back where the gas tank and spare tire used to be. The area under the hood could easily hold half the modules if that was necessary.

Look up Marc Bishop's Honda Insight. I will attach some photos if I can find them.


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## Caps18 (Jun 8, 2008)

The lifetime of the batteries would be the next issue. If you are depleting them more than 80%, the will only last a few years. 

Here is a normal suggestion, and an out there one. 

Normal, buy a new Chevy Volt. 50 mile EV range, can be recharged at work for around 100 EV miles a day.

Out there, buy the same Chevy Volt, but come up with a way to add a second, larger battery pack.

The best option would be to wait until the Chevy Bolt comes out and use that. 

If you were 50-60 miles away from work, a DIY EV can be done, but 125 miles along with wind and weather conditions is probably too much.

^I do like that Insight up there. That looks like how Honda should have made it in the first place.


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## madderscience (Jun 28, 2008)

Its worth pointing out that 250 miles a day, or 50,000 miles a year just for the commute is going to wear out ANY car (EV or not) in 3 to 5 years. Heck, with an ICE car if you follow the oil change every 5000 miles routine you are changing oil once a month. 

This is a LOT of driving. Stuff is gonna wear out whether its OEM or homebuilt. 

With a homebuilt insight conversion you would have the ability to pull out all the stops to strip down the body of any unnecessary weight, and do anything you can to optimize the aero (though with an insight its already almost as good as you can get) But its gonna be a lot of work to build it.

As for battery cost, a friend of mine recently bought a used 2014 leaf that had only a couple thousand miles on it. He has a long commute (80 miles or so round trip, not 250) and then wrecked it a couple weeks later. Ouch. The insurance company assigned the salvage value at $3000. So at least in this case, he could have had a near new 24kwh battery for $3K (rest of drivetrain was still functional too apparently). If I had known the wreck happened I probably would have bought the thing...

@dougingraham


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