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Discussion Starter · #1 ·
So, I have another idea. This one doesn't require so much hack and slash to the car as my first one. (if it works I'm doing it to my daily-driver too)

I should probably patent the idea.. but nah, I'll just copyright the software controller :)

MX-6 - Hybrid AWD drive! A little extra weight in the back for a lot more power, superior launches, and better weight distribution :) Win-win-win scenario. This will work on ALL FWD manual cars.

Here's the idea. Gank the lithium ion battery pack from an old possibly wrecked hybrid car or just buy a replacement pack, they're going way down in price. Mount it in the trunk.

Get a pair of decent electric motors, hook them up to the back wheels.

Get a beefier alternator.

Build yourself a car-puter and with some off-the-shelf components write yourself a program to power the motors and monitor the charge in the battery.

Benefits? A whole lot more torque and power in your acceleration, then when you're just cruising the electric motors need no power and you can charge your batteries. Should you totally run out of juice the motors just won't do anything until you have charge again.

How to control the motors:

In most hybrids the motor is part of the power-train. In this setup, the motors will form a separate propulsion system on the rear wheels, so it will take some thought to design the software controller.

The power going to the motors should be based mostly on the throttle, speed, and the clutch. If the clutch is in or the car is in neutral then all power to the motors needs to be cut. This is a safety issue and would allow the vehicle to coast along in a predictable manner when the transmission is disengaged.

In reverse the motors should also be disabled. This adds simplicity to the system by negating the need to switch the currents to power the car in reverse.

Unanswered hypothetical questions:

How should the power going to the rear wheels be handled? Assuming the voltage to the rear wheels is scaled to the throttle, would it be a problem if say the rear wheels are putting out 50% more torque than the front?

I'm not sure if the engine would just rev up faster with less load, or if the motors have too much torque and actually cause engine compression braking although that shouldn't happen with the throttle open. In theory with really powerful motors this seems possible, although I don't think it would ever actually happen.

How do electric motors handle running with less load? Do they suffer the same sort of parasitic losses that an engine does, or do they just wind right up with no trouble?

Fun factor:

There is a lot of control with motors. You could program in oversteer. Load up your drift profile and the rear wheels will always more torque than the front wheels and maintain 5-30mph faster spin than the front wheels when they break free.

Or, opposite of that, you could program in a stabilitrak sort of system where power is cut to the right or left motor if a skid is sensed.

Conclusion:

This is a totally cool concept that is a lot easier to do than my first 'call me crazy', it's also legal, and it's completely tunable without breaking any sort of emissions laws since you're leaving the motor alone.

What do you think?
 

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Good luck. :rolleyes:

While in theory it would be fun, it's not cost efficient to make an mx6 AWD when you can buy an older wrx for under 10 grand. Also, I saw a truck with an electric motor on pass time and it had a TON of motorcycle batteries that only lasted one or two runs. You're talking about full time power to TWO electric motors. For all the added weight from the batteries I think a turbo FWD Mx6 would tear you a new asshole.
 

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Discussion Starter · #4 · (Edited)
lol.. you gotta read the whole post before you say it's not practical.

This isn't a traditional AWD power train like the WRX or Evo.

You have to use your brain a bit and think outside the box.

Front wheels - full time engine powered.
Back wheels - part time electric powered.

Power comes from a battery pack like that in a Prius or Insight.

Weight? Motors might be 30 pounds each. Mounting hardware? 20 pounds. Battery? 50-100 pounds. Computer and wiring equipment? 5 pounds.

At the most we're looking at 250 pounds for what could be a tremendous amount of power on a hard launch. I just have to get the right motors and be able to drop a ton of amperage into them :)
 

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I'll echo my comment in your first thread. Pipedreams.

Sorry if I dont appear to be "thinking out the box" but unless you have seriously deep pockets and huge resources, you wont pull this off.

I am not saying it is impossible, just very improbable. MHO only.
 

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20 pounds of hardware? did you miss a zero there? motors that powerful will need a BEEFY mount, and a heatsink to match.

The alternator would draw mcshitloads as well, enough to slow you down to get rid of the difference..

unless maybe you made the winds inside the rims and had stators around the axle, but thats just as much work, and would get fried when the suspension starts moving...

mx6 is fine the way it is, they can be made to run 13s which is more then enough accelaration to have fun at the twisties, you start screwing around with the rear end and you are gonna get not much benefit for the cost of multiple compromises. If launching is a problem, learn to drive.
 

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Discussion Starter · #10 · (Edited)
There are hybrids in development like the Chevy Volt & BMW's electric Mini which have powerful motors in all four wheels and an engine to run a generator.

It's practical for these cars without weighing them down. The motors they're using are 50-100lbs each. They're quick too. No numbers on the Volt so far but the electric Mini does 0-60 in 4.5.

From what I'm reading here, you'd think these electric-motors-in-the-wheels cars would weigh 10,000lbs, cost a half million dollars, and get to 60mph in a good thirty minutes.

I know how to drive, thanks. AWD > RWD > FWD, and you know this. I'm aiming for something a little better than a 13 second quarter mile. I'd like to do it without spending money on an illegal JDM swap with unknown mileage history. By now you should be getting the point that I don't want to do something that's been done before.

The whole point of hybrid cars like the Prius and Insight is because the electric motor has 100% torque available at 0 rpm. This helps push the car until it's at a speed where the engine can handle the load more efficiently. It's not too hard to imagine this as a performance system where beefier motors viciously catapult the car into the engine's power-band and continue to help acceleration.

BTW, its not full-time power to the motors. They turn on in acceleration, and rest while cruising. The power to the motors is based on the engine's throttle. If the throttle is only open enough to sustain a cruise, the motors are off and the battery is charging. C'mon guys, you know how hybrids work.

The trick is to find the right motors.
 

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Discussion Starter · #11 ·
unless maybe you made the winds inside the rims and had stators around the axle, but thats just as much work, and would get fried when the suspension starts moving...
Siemens is developing a motor exactly like this, it's called e-corner. It's a donut shaped motor that is the wheel itself, is integrated with an electric brake, and the whole thing is pretty lightweight. Awesome innovation.

YouTube - Siemens VDO eCorner Project:
 

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Discussion Starter · #14 ·
do it dude. sounds cool id like to see how it goes. mby get rid of the independant rear use one motor and use like a good rear dif.?
Yeah, depends on what I can get for motors. There's a company that does hybrid conversions but they mainly work on automatic transmission RWD trucks and SUVs. They basically stick an electric assist motor on the drive shaft, and a couple lead acid batteries in the back. It almost doubles the city mpg, believe it or not.

I could use a drive shaft & a differential and one big motor, or I could use two smaller motors and a pair of shafts from a FWD car. Depends on which would be the better power/weight ratio. Using two motors would allow me to keep the independent rear suspension.
 

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Yeah, depends on what I can get for motors. There's a company that does hybrid conversions but they mainly work on automatic transmission RWD trucks and SUVs. They basically stick an electric assist motor on the drive shaft, and a couple lead acid batteries in the back. It almost doubles the city mpg, believe it or not.

I could use a drive shaft & a differential and one big motor, or I could use two smaller motors and a pair of shafts from a FWD car. Depends on which would be the better power/weight ratio. Using two motors would allow me to keep the independent rear suspension.

or get like a vette rear dif and have independant.. im just lookin at this at a cost issue.
 

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Discussion Starter · #16 · (Edited)
Anyhoo, I'm not having any luck finding the motors that are being used by the hybrids that are both lightweight, powerful, and reasonably affordable.

Instead, I'm finding behemoth monstrosities that weigh hundreds of pounds, cost tens of thousands of dollars, and still only produce 50 hp. I e-mailed a bunch of electro-drag-racers for their ideas, we'll see if they have any alternatives I've missed.

Anyway, back to what now seems like a not-so call me crazy part 1. I've decided on an engine, at least. The Cadillac Northstar L37 V8, oh yeah, oh right. It's automatic, so that should spare me from the hassle of having to fabricate a shifting mechanism. 300 ultra-smooth caddy horses, that's what we need. That's 300 horsepower from a stock engine that should put me at or very close to a 1:10 power to weight ratio. Should I decide to convert my MX-6 to a non-street car I could turbo that up to 400 easy :)

I'm checking in with the boys at the Cadillac forums to see if I can't get some of their smog-test info. If it lines up within the ranges on my recent smog test on the MX-6 then I'm good to go :D
 

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if you are going to do that than you should also just throw in a V8 crate motor with 600 hores and add a transfer case too... you would have no problems with launchs and would have a badass ride
 

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i had the same idea a while back, basically the weight and cost are pretty big determining factors. my plan was to fit 2x hi-pa drive 120kw in wheel motors to the rears, because of regenerative braking they could recharge while driving/breaking. in theory it was a great idea but the cost would be about $30,000 not to mention the company the sells the motors wouldnt even reply to me emails and the weight of the batteries would be pretty large (i only ever planned for mine to last 15sec off a full charge to keep battery weight down) but dont listen to the haters, hybrids in this form will become very popular in a few years.

i really dont see why theres so many stupid comments about this. i can honestly say it would tear the arse out of anything on the road even with the high weight, 1500nm of torque at the rears at idle would be quite nice.

Hybrid electric cars, electric cars UK, electric vehicle conversions, hybrid motor vehicles
The 640 bhp MINI QED plug-in EV
PML Builds 640hp Electric MINI
 

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There are hybrids in development like the Chevy Volt & BMW's electric Mini which have powerful motors in all four wheels and an engine to run a generator.
and engineers that know wtf they are doing, and not just trying to retrofit what will likely turn out to be a hackjob onto a 15 year old platform.

there is no benefit to doing this. It won't make your car faster, except for the first few yards.

your weight estimates are WAY off. do more research, but if i were you, a conservative estimate should be more than twice what you came up with. powerful motors require... power. a battery or two out of a hybrid won't cut it.. you'll need a full battery setup from said hybrid.. which weighs a lot more than 50-100 lbs... or you'll need 6 or so optimas wires in parralell/series combo to achieve the reserve you wish to have.


There's thinking out of the box... and then there's thinking out of your league and ability.

while its a nice thought, what you're thinking of... your complete casual attitude about it.. as if it'll be a walk in the park.. shows you have absolutely no clue, and are just putting things down on paper with too much dream, too little actual research.

There are plenty of DIY electric projects. I would draw experience from those guys... the only difference is you won't be removing all of your running gear, only supplementing.

your idea would be better served as a gas mileage saver.... but as a performance mod.. the added weight and limited capacity will likely just hurt you instead.

**edit, and then you switch gears and want to throw a northstar v8 into your 6 lol. AND your biggest concern seems to be smog test info... lol? in case the obvious hasn't ocurred to you yet.. the mods you're planning will place you firmly in the "i have to bribe someone to pass inspection" territory.

proof of concept or ban. have you even measured one yet?

I have.

It's too tall.. won't fit under the hood unless you cut half of the hood out, and put a ridiculous scoop on it... secondly.. its an east west engine.. but to fit it between our subframe rails up front, you'll need to mount it north-south... which won't do you much good.


you seem to have far more opinion than knowhow.. sorry buddy.

I'm going to file this under "newb projects that will never happen"

talk to me in 2 years if i'm wrong.
 
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