Electric Assist Project: E-charger (2000 Subaru Outback)

[ademonrower]

I admire your motivation and ingenuity! I'd been considering doing this kind of thing with a European manual car from the 1970s, i.e. where the technology is very basic, and there's loads of room in the engine compartment! I really like the idea of the e-motor driving the crank pulley via a belt, thereby taking load off the engine directly. I am assuming that your Subaru has automatic transmission. I suspect that that might work better than manual in this situation, but correct me if I'm wrong. I'm basically hoping that manual tramission will be no hindrance to doing a project like this. I'm sorry I don't have advice for YOU, but I don't have a hairswidth of the experience that you do in this area :-/ Thank you!

[Logic]

Originally Posted by ademonrower

I admire your motivation and ingenuity! I'd been considering doing this kind of thing with a European manual car from the 1970s, i.e. where the technology is very basic, and there's loads of room in the engine compartment! I really like the idea of the e-motor driving the crank pulley via a belt, thereby taking load off the engine directly. I am assuming that your Subaru has automatic transmission. I suspect that that might work better than manual in this situation, but correct me if I'm wrong. I'm basically hoping that manual tramission will be no hindrance to doing a project like this. I'm sorry I don't have advice for YOU, but I don't have a hairswidth of the experience that you do in this area :-/ Thank you!

I do too. It's just all those extra controls I feel would be better integrated with the existing controls.
Combining the throttle with the motor throttle and the brakes with regen should work OK and quite easy.
I haven t read this thread in a while and dont know what your skill and research level is so forgive me if I'm repeating stuff.

NB the the belt pulls on the PULLeys of the ancillaries.
So when the engines crank pulley is pulling on the belt its under tension until after the last ancillary.
After that it would be slack back to the crankshaft if it wasn't for a spring loaded tensioner 'pulley'.

When the pulling is elsewhere on the belt and pulling on the crankshaft pulley, the slack is on the other side... So 2 tensioners are required.

Also look at the mountings of the various ancillaries.
Are they strong enough to handle the extra tension on the belt?

Also NB that this method does not work if the engine is off as you then have to drag the engine along through a whole lot of compression etc strokes.

As you're in Germany your neighbor is likely to have a lathe and milling machine in his garage and do excellent work.
He will be able to build an electric motor into your gearbox before the gearing.
ie: You keep the gearing, allowing you to get away with a cheaper smaller motor, just like the one for your original plan.

This way the engine only drags on the motor when the clutch is engaged and you get to drive with the main engine off and get better/more regen.

The disadvantage is the constantly depressed clutch and constant turning of the clutch release bearing that is likely to wear is out way sooner time wise.
Also the other ancillaries on the engine belt stop working, as does your engine vacuum powered brake assist.
With EVs at the scrapyard nowadays you should be able to find electrically driven replacements for all these.

[ademonrower]

Many thanks for those very good points! Thank you also for making one thing clear: that if I can get the machining done, or do it myself (fortunately I have a lathe), the motor before the gearbox would be the better option. There are a few manual transmission hybrid cars these days, e.g. the Fiat 500 and Ford Fiesta... must be a few on scrap yards somewhere. Fiesta would be good, because it's nearer in weight to my car. I have no idea, but I might be able, essentially, to use the components and electronics, adapting them around my car. I think this one rates as "ninja" on the scale of Ecomodder modifications, right? :-)

[Logic]

Originally Posted by ademonrower

Many thanks for those very good points! Thank you also for making one thing clear: that if I can get the machining done, or do it myself (fortunately I have a lathe), the motor before the gearbox would be the better option. There are a few manual transmission hybrid cars these days, e.g. the Fiat 500 and Ford Fiesta... must be a few on scrap yards somewhere. Fiesta would be good, because it's nearer in weight to my car. I have no idea, but I might be able, essentially, to use the components and electronics, adapting them around my car. I think this one rates as "ninja" on the scale of Ecomodder modifications, right? :-)

"...I have a lathe..." See; I knew that! lol!

You're talking about those Motor-Generator-Starters that fit between the engine and gearbox on some hybrid models right?
They may be made to fit with an adapter plate/s etc, or perhaps fit the whole clutch-motor-gearbox assembly to your engine/car if the ratios and specs are similar enough.
That's certainly Up-There as far as an Ecomod goes.

I would say that putting a gear that matches the gear teeth on the input and/or counter shaft on a motor and fitting/mounting it to the gearbox is likely the better cheaper option.
You might even be able to mount the motor direct to the end of the counter shat if the motors rpms match. It all depends on your specific gearbox.
(You may have to mod the car's transmission tunnel some, somewhere to make space for the motor, but that's not a biggey)

(This shows the gearbox basics for those wondering)

https://www.youtube.com/watch?v=wCu9W9xNwtI

This shows cutting and weldng engine crankcases etc to make a 2 cylinder from 2 one cylinders.
As similar modding to your gearbox would be required, it serves to show that cutting, welding and machining a gearbox like casing is pretty straight forward. Inspiration!

https://www.youtube.com/watch?v=4Lafg4XwL-Q

One last thing: While a PM magnet motor is efficient it would 'drag' on the engine when not in use.
A motor with a DC rotor winding is cheaper and you can just cut power to the rotor for coasting (most efficient conservation of energy) and when you don't want to use it like if there's a fault somewhere.

Playing with the rotor voltage opens up all sorts of opportunities! (higher rpm ranges, settings to match controller/regen, etc)
So this cheaper motor option may end up being more efficient overall..?
Some of the alternator stuff being looked at:
https://www.mdpi.com/2075-1702/10/6/478

[ademonrower]

Thank you very much for those very useful details: much for me to think about! I have a couple of pals who could help me. I even know someone who converted an old Volvo 850 to complete electric, but I'm not going to do that: need the car for longer journeys :-) er, and it wouldn't be much of a classic anymore...