# 1985 VW Cabriolet *Build Thread*



## Yabert (Feb 7, 2010)

Hi bwjunkie

Nice car and conversion. You will enjoy it.
But take care to do it right in the first time. Few points:

1-The Warp 9 can produce over 150 lbs-ft of torque at 600A. It's serious torque and your motor mounts don't seem strong enought. Especially the small strap with holes. 

2-The motor and transmision shafts need to be precisely aligned. Adapter plate is generally precisely aligned with the transmision with pins. Done? 
And do you have pics of your motor coupler?

3-And about your range of 40 miles, it's probably more realistic to expect between 25 and max 35 miles (at low speed). Don't hesitate to go 48S (or more) if you can (I saw bms 48S). That will give you 6-7% more power and range.

Good luck and continue your good work.


----------



## bwjunkie (Jul 31, 2013)

Thanks for the input Yabert, couple things:
I don't really understand the term 48S but does that mean 48 cells?

Regarding motor mounts, I kind of agree with you. I have a total of 4 mounts for the trans/motor assembly, and it's really not enough long term. I want to add a 5th mount to the top eye-lift bolt of the motor with 1/4" angle iron but just looking for good places to secure it to the engine compartment. Also I can double up the 1/16"x1.5" steel strap you mentioned so it isn't such a weak link.

Range: I've been concerned about that for a while, but not too concerned, I could survive on 30 miles, just not ideal. I wonder if I can go up to 200v as a solution?

My adapter plate came from EVAmerica pre-cut for this motor and they provided alignment pins as you mentioned to get the transmission bolts in exactly. A total of 9 bolts hold the trans and motor to that plate, so hopefully it's strong as a single unit.

The coupler is a small steel hub on the motor side attached to a modofied clutch plate connecting to the splines on the trans, this was all designed by EVA. My only picture of this doesn't really show the hub which is on the back side of the plate on this pic: 









thanks again, any input is very helpful to me.
Josh


----------



## Yabert (Feb 7, 2010)

bwjunkie said:


> I don't really understand the term 48S but does that mean 48 cells?


48S mean 48 cells in series (48x3,2v = 154v nominal)



> Range: I've been concerned about that for a while, but not too concerned, I could survive on 30 miles, just not ideal. I wonder if I can go up to 200v as a solution?


Yes, if you add 60ah cells (say 62S for 198v nominal) that will give you more total energy, you range will be higher.
Another good solution is to complete your conversion like you started and double your cells count by adding another 60 ah cell on each used 60 ah cell when you will need more range.

Example: 
45S 1P = 144v and 60ah for 8640 wh of energy (8,6 kwh)
45S 2P = 144v and 120ah for 17280 wh of energyy (17,3 kwh)


----------



## bwjunkie (Jul 31, 2013)

Somewhat major setback occured today when I went for another test drive (with 2 added motor mounts) to see how things felt and listen/watch for vibrations etc. As I was coming home I lost power to the drive train but the motor was still spinning up (but did not over-rev). And was definitely not spinning the trans in neutral either, just zero drag.

I looked through the open hole where the old starter motor used to mount on the trans, and could see that the coupler/clutchplate system was not spinning either, so I guess that means the splines are not stripped. My guess is the coupler slid down the shaft and off of the motor? I was not under heavy power, in fact I may have been coasting somewhat (as I crested a small hill).

I suppose the good news is, nothing sounded like it was breaking or tearing, there was no loud sounds, just lost power while going slow. still a bummer, as I will have to remove the motor at the very least. Possibly also the trans (hopefully not).

Other minor good news, the switches I put in the dash to power up the controller and the contactor are working, plus my rear lights are working. And it was nice I didn't have to tow it back, I was able to roll far (because I took the time to pump up the tires extra firm) small victories. 

Other minor bad news I could not get her in reverse, my shifter linkage must not be quite right.

josh


----------



## bwjunkie (Jul 31, 2013)

I finally got around to removing the gas tank, and can now consider the large protected space left behind for a battery box, in front of the rear axle instead of behind, for better driving stability hopefully.

The yellow outlines possible cutting areas...



underneath:




the tank, eww:


----------



## hbthink (Dec 21, 2010)

I've got an 83 Cabby, using Soliton Jr and 20 Valence 12.8 x 40ah batteries which gives me a range of about 35 conservative miles, although I've managed 40 going boulevard and keeping speed down, with coasting. Car is about 100 lbs lighter than stock, stripped it bare. I used a composite material for the battery boxes. An FB4001 powers it similar to your Warp 9. I broke the original lower motor mount and replaced with new one its been fine since. I setup the Soliton for range vs less startup power and that solved a lot of the excess torque problems. Cabby's make great conversions! Love mine.

http://www.evalbum.com/4204


----------



## bwjunkie (Jul 31, 2013)

Awesome Steve, looks great!

I love the "mini atx computer" idea, I'm doing similar with a Raspberry Pi and a 3" touch screen. This choice has proven to be quite a lot of extra work, I'll have to write a x windows GUI in python because Java is quite sluggish on the RPi, but it's moving along okay (only needs 5watt!).

Your range sounds decent to me for what you are using. I too have a very bare bones conversion, heck I'm stilldriving around with no vacuum brake booster and I just capped off my old power steering lines, and it steers easy.

When your mount broke did you have another mount on the back of the motor going up toward the top of passenger side strut?

I'm also wishing I had a clutch, I'd really like to use 1st gear often to better manage the power-band from starts.

Did you put any batteries where the old gas tank went? I'm kind of excited about this new idea, but still not sure what I'll be making the boxes out of.

Josh



hbthink said:


> I've got an 83 Cabby, using Soliton Jr and 20 Valence 12.8 x 40ah batteries which gives me a range of about 35 conservative miles, although I've managed 40 going boulevard and keeping speed down, with coasting. Car is about 100 lbs lighter than stock, stripped it bare. I used a composite material for the battery boxes. An FB4001 powers it similar to your Warp 9. I broke the original lower motor mount and replaced with new one its been fine since. I setup the Soliton for range vs less startup power and that solved a lot of the excess torque problems. Cabby's make great conversions! Love mine.
> 
> http://www.evalbum.com/4204


----------



## bwjunkie (Jul 31, 2013)

I received my Vicor Maxi DC / DC today, and wow is it tiny!
Not really sure how the "evaluation board" is going to fit into the picture, but I'm kind of glad I bought it...

Also my Raspberry Pi which is now running the Orion BMS software via USB to the unit, but I will be programing my own lite version to show minimal diagnostic data. The 7" display is not touch, and I finally realized I didn't want that thing in my car along with some sort of mouse/keyboard contrpation. Besides at $150 it was too expensive to have laying around a convertible VW. At $35 the Raspberry Pi is a reasonable loss.











So anyway, this Vicor, and evaluation board (which might get relabeled to "production board" by me), I don't really know how to start with it, I suppose I'll just hook it up to my traction pack and see if it blows up.










and the front side faced down into the board:









*shrug* anyone got a suggestion on what to solder first?

it's so tiny! reminds me of a deck of cards, so maybe I should head to Blackhawk and play some NLHE tomorrow? Live Casino Poker really is a lot closer to a slot machine than you'd think.


----------



## Semper Vivus (Apr 13, 2011)

Is that dc dc an isolated version?
Regards
Tom


----------



## bwjunkie (Jul 31, 2013)

Semper Vivus said:


> Is that dc dc an isolated version?
> Regards
> Tom


I have no idea, here is the diagram. Kinda looks isolated?


----------



## favguy (May 2, 2008)

Yes, they are isolated, I used 3 of these, similar to yours but at 150 watts to make my DC/DC.

Your single module at 500w appears to be no larger, incredible!


----------



## bwjunkie (Jul 31, 2013)

ya I was astounded by the small size. (that's what she said?)

After scary fun with a reciprocating saw, and nearly destroying my car?
Last night I did a pegboard mock of my sub-level battery holder. Here is some pics.

first the scary hole (opps did I just ruin my EV?)
The large angle iron seen is the rear axle, has no vertical or lateral movement but it does swivel slightly so nothing can be touching it.









more cutting, and then the pegboard mock...









overhead shot, make sense? Total of 3 rows of 15 batteries = 45 = 144v
just the thought of moving this weight lower and in front of the rear axle makes me happy from the viewpoints of suspension/handling/catastrophe









is it okay to have 1 row of batteries laying on their sides? I'm pretty sure I read that it is okay but still not certain.


----------



## bwjunkie (Jul 31, 2013)

battery box ideas...

I got impatient waiting around for welding quotes, found the best sheet metal surplus I could ever imagine and after a total $30 on 30 sq ft of 16 gauge steel, I have begun to weld for the first time in 20 years! 
Bought a little $500 lincoln electric MIG, $110 on a new tank of Argon-CO2 and shabam, I'm a welder? decades ago I only welded Stick and Oxyacetylene but MIG is nice so far.

Here is my first box... mostly just tack/spot welded for the moment until I see it will all fit right, and the sides were folded up, which is nice but a pita with no proper sheet bending device. I'm still debating on how to bolt the box to the car (I don't want to weld it to the car for some reason)
Despite the shiny appearance, it is not stainless, so will need some primer/paint or powder coating maybe someday when I feel like a boss.


----------



## bwjunkie (Jul 31, 2013)

In the last 3 weeks I went from: batteries in the trunk...








to chopping up my car








to Mocking up an idea that seemed fairly easy








to these finised metal boxes, which wasn't easy... 









lots of new skills learned, people and places met, and a few scratches. no burns or ruined eyes or ears!


----------



## bwjunkie (Jul 31, 2013)

I'm vaguely thinking about moving all my parts to a 60's Chevy Corvair chassis. Which did also come in convertible, but living in Denver convertibles as your only car, is a love/hate relationship, so the hard top would be a consideration

The two main reasons are:
1. I feel the suspension options are better, even if I do ever figure out my VW springs quandry, I don't know if the wheel base and general design is living up to it's german name. This becomes more important as I look into adding more battery weight for increased range. I'm SO proud of my welded boxes into the old gas tank spot, but even so, I can feel the entire chassis wiggle with a fever in it's belly.

2. I really want a clutch. I not a fan of my current clutchless system. So if I'm really going to be switching out my adapter plate system and re-building some motor mounts for the change, it might be a good opportunity to push those efforts into a dream chassis like the Corvair.

3. I don't speak _Deutsch_! 4. My drums are more likely to fit in a corvair. 5. My dog is less likely to fly a mile during a medium speed crash.

thoughts?
josh


----------



## mk4gti (May 6, 2011)

You have to calculate if your current gear can swap over to a bigger, heavier vehicle. I went from a 1700lbs car to a 2100lbs and I notice the range/ power is not the same.


----------



## tchapin (Feb 2, 2011)

If you go the corvair path. go for a 1964 and newer. That is when they added the mono leaf spring to the rear end. Personally I would go with the last body style 1965-69. The early style looks like a bathtub on wheels. Esp. the convertibles..


----------



## bwjunkie (Jul 31, 2013)

Hi, thanks for the input tchapin

I agree about the rear suspension, I've been looking into that. 

I've got my eyes on some '64 models, I actually like the older design more than the late 60s one. For me the later model is more of a "plain musicle car" look which fine, but so far I prefer the funkyness of the older "hint of 50's" look.

josh


----------



## twright (Aug 20, 2013)

The upgraded Corvair suspension started in 1965.


----------



## Wilfred (Mar 26, 2014)

Hey bwjunkie

I am really interested how you got the gas tank off? I've been looking at mine to think of the best way to get it done but I have a feeling I'll just end up taking my jigsaw to it like I have to so many other things .....

Also if you could lead me to some insight as to how you rigged up the motor / transmission to be clutchless? And why you've come to the conclusion that you'd prefer to have a clutch? Or is it solely for the full range ? I was thinking about that as an option for mine

Thanks!!


----------



## mk4gti (May 6, 2011)

Rear axle beam has to come out, then you remove the metal straps holding the tank and a few bolts. Also remember to remove the wiring for the inside pump/fuel level sending unit. Easier if the tank is empty so pump the fuel out using the intank pump and a small 12v battery.


----------



## bwjunkie (Jul 31, 2013)

I did not remove the rear axle, but only "lowered" it maybe 8 inches or so. There is a tutorial on the cabby forums, I'll see if I can find it or you can search for it.

I kept my rear brake lines attached and lowered the rear axle to the max the brake lines would allow which also involves detaching the struts with their lower bolts. This is a pain in the booty, and leaves barely enough room to squeeze the gas tank out, which then is a bit of a wrestling match. 

If you drain and detach the brake lines then you can drop the axle further to the ground and would have more room which is what mk4gti is saying.

I don't know how difficult it is to drain and detach the brake lines because I never tried it.

josh


----------



## bwjunkie (Jul 31, 2013)

Wilfred said:


> Also if you could lead me to some insight as to how you rigged up the motor / transmission to be clutches? And why you've come to the conclusion that you'd prefer to have a clutch? Or is it solely for the full range ? I was thinking about that as an option for mine


In my case evamerica sells aluminum plates and a hub connected to clutch plate with splines made for your car, this results in a clutch less drive system for the EV.

the shifting issue is a ramble of preferences and nuances, but here it is:

I have to shift from 2nd to 3rd and back to 2nd since I have a smooth toll freeway nearby where everyone drives 85. Then moving to an offramp or another slower freeway I've got to downshift back to 2nd, which is a lot more difficult than upshifting but not terrible.

I never use 1st gear, because getting in and out of it is a pain, but I wish I could because darting across moving cross-traffic is no fun in 2nd gear, the lag time to reach my motor's powerband is longer.

Also when cruising say 30mph and a distant light up ahead turns yellow, I would normally (in a gas car) engage the clutch and coast, or pop into neutral and coast. But doing this in a clutchless EV results in future problems because if you are still coasting 20mph in neutral and the light turns back to green now you have to get back into gear, which means revving up an electric motor which has only a lightweight clutch plate attached to it (no flywheel). I do it often but really it's not a good idea. I could just in 2nd and roll toward the red light, but then there is a slight noise and drag from the motor., This is a matter of preference and habit, but seems odd to me and does reduce the coasting distance, I can feel and hear the difference.

Finally the experimental reason is getting the torque off the line that is provided by a flywheel. (disclaimer: I really have no clue what I'm talking about)
In a gas car you can get a tiny jump off the line (from a dead stop) which is sometimes needed, by engaging the clutch on a spinning flywheel.

In fairness to clutchless system designers, I'll say my shifting linkage is sloppy and probably has contributed some to my poor shifting experiences. But we shall see! because I'm going to build a super dope 1965 mk1 Cortina EV, which WILL have a clutch. 
fun ramble!
josh


----------



## Wilfred (Mar 26, 2014)

Thanks for that!! I probably won't get rid of the tankf for a while, it seems like a pain and right now I'm just working in my backyard...

I also don't know much of what I'm talking about... But it seems even when people do use clutches, they only use 2nd and 3rd anyways because EV motors give out pretty much all their torque right away and 1st gear would just be a lot of spinning out? Does your car spin out in reverse if you're not careful?

As for coasting... You say there is a noise and drag if you stay in gear and just take off the throttle? I am just not 100% sure if that's what you were saying...

Also it'll be fun to see your new build!!


----------



## bwjunkie (Jul 31, 2013)

thanks Wilfred, the Cortina is going to be a really exciting adventure.

I have never spun-out the tires, and it seems unlikely that it is even possible in my car even with 1st gear or reverse. But also I have my controller set to 350 amp max. Changing this limititation might offer more possibilities. But really... I can already easily drive 85 mph, does it make sense to raise my max current just to gain torque that can come from the flywheel/gears?

re: coasting drag/noise. Yes, when at 0 throttle in 2nd gear moving 30mph, the electric motor has a small amount of drag and noise. In contrast to rolling the chassis in neutral I feel it's quite noticeable and detracts from the driving experience (<- lol). I could be partly why some EV's feel like a golf cart, due to lack of contrast. How is this different from an auto-trans, I have no clue!

I don't know about the max torque from 0 rpm either. I was guessing that final power to the wheels still be dependent on gear ratio? 
Anyway I plan to find a way to get a small jump off the line to dart across traffic. If this comes from 1st gear or from flywheel torque (or both) I don't yet know, but I'll have both methods available to experiment with.

josh


----------



## Wilfred (Mar 26, 2014)

Experimentation is definitely the best way to learn!! 

Well those problems I can learn to deal with... I was not paying attention when I sold the engine and the clutch and flywheel went with it... And I'm pretty sure couplers are easier to install which is good for me as this is my first conversion 

BTW if you end up starting your new project soon I'd be glad to buy your vw coupler  haha


----------



## bwjunkie (Jul 31, 2013)

I'll keep ya posted the the adapter plate. I just drove around a bunch today, and I really think the clutchless system is fine, it's just I'm being a little nitpicky and want to try with a clutch because I "think" I'll prefer the results.

Keep me posted on your build as well! and send me a PM if you need to talk voice about any issues, I'll do my best to be of help.

josh


----------



## Wilfred (Mar 26, 2014)

Thanks for the offer! I'm kind of at a standstill right now because it keeps raining  but when I'm able to get into it again I'll probably have some questions haha


----------



## onegreenev (May 18, 2012)

Clutch vs no clutch. If you aways drive like a hyper miler then clutchless should be just fine for you. However if you drive even remotely aggressive the clutch is real handy to move into and out of gear. If you go with a clutch or even clutch less you will need to be sure your shift mechanism is in top shape. With the old vw you also have your shift shaft bushings to contend with and those must be in top shape as well. If your car sifts crappy now it will shift crappy with or without a clutch but without, since your doing things much slower, won't be noticed as much. 

It is no longer an experiment. Also you can change the R&P and move your shifting points to better take advantage of the torque. I am using gearing in my bug that were used in the Type III as well as using a 3.44:1 R&P. I still don't use first much but I can actually go a bit faster in first now so if I need it I can use it. It is excellent on the freeway.


----------



## Wilfred (Mar 26, 2014)

Well I never really got to drive the car much before I took it all apart , but from the little I did it shifted well enough I suppose.... It wasn't the greatest to be honest. But then when I went to drain the tranny there was no fluid!! So I don't know how is actually haha


----------



## bwjunkie (Jul 31, 2013)

shhh!

This build will soon become "this" build, hehe...

gotta remove the 302 small block first...



























I simply cannot contain my excitinment about this car!
-josh


----------



## Duncan (Dec 8, 2008)

Hi Josh
If you are going for a light car like a Mk1 Cortina
What about throwing the gearbox away completely?
Just go direct drive
This would mean you could put the motor where the gearbox used to be and have the whole engine bay for batteries
Does away with all of the nonsense about clutches

I have direct drive in my car - its fun
I can't quite spin the rear tires with 500 amps - but I have 55% of my weight on the back wheels


----------



## Wilfred (Mar 26, 2014)

Looks like its in really good shape!! I'm excited to see how it goes


----------



## bwjunkie (Jul 31, 2013)

Duncan said:


> Hi Josh
> If you are going for a light car like a Mk1 Cortina
> What about throwing the gearbox away completely?
> Just go direct drive
> ...


Hi Duncan,
I have not thought the transmissionless option at all, but I think it is worth consideration, a couple questions since I'm using Warp9 DC. 
How would I use Reverse?
Would I need a gear reducer for 0 - 80mph? I know my 13inch wheels help somewhat but I'm still unclear on my max rpm.

I am kind of wondering if this existing T-5 (mustang GT) transmission might just be very heavy.
Josh


----------



## bwjunkie (Jul 31, 2013)

Wilfred said:


> Looks like its in really good shape!! I'm excited to see how it goes


thanks Wilfred,

It's nice but thankfully not restored showroom quality so I didn't spend too much for it, and I don't feel guilty drilling a few holes here and there.

Also the entire rear end / drive train is shortened late 80s Mustang GT with a 5 speed and V8 302 roller-cam. I thought I'd drive it a year before converting to EV, but this thing is seriously not a daily driver with 300+hp, lol, it's more like a track-day race car. When it comes to racing I'm strictly a 2 wheel guy (TZ250!). I need something I can drive everyday to work without getting tickets every 20 feet, so I'll probably sell the engine soon, and with some additional batteries, maybe this car can be a 60 mile range!

I'm happy because it is so dope, but also it is worth putting serious money into the suspension etc. which I didn't want to do with the VW Cabriolet.
josh


----------

