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Guys, I need some advice here as I have virtually no experience with automatics, only manuals.
I don't want to get sidetracked debating man vs auto in general, but as it applies to my particular situation I will consider all options.
My situation is a little bit unusual. Please take a quick look at this motor and attached pics:
http://www.remyinc.com/docs/HVH250R4.pdf
I picked up an engineering lab prototype off ebay which seems very similar to the HVH250. It differs in looks in that there is a hollow shaft, splined on the inside and on the outside there is a helical gear. Looks like it should plug into a planetary arrangement. I'm thinking that this may be one of the motors from Chrysler's 2 motor transmission project. Even if it doesn't end up with as much gusto, on both accounts it appears that it is intended to be filled or totally submersed in ATF. This oil is also used for cooling, I do not yet know if it's self pumping or if I need an aux pump to push ATF through it. But it is a "special needs" motor.
This is going on a RWD car (1981 bmw 633).
My original plan was to fit the motor straight to the differential, but that was before I got this thing with it's ATF needs and the available ratios are kind of low. I would prefer to maintain stock diff to keep my final drive ratio options open, typically in the range of 2.73:1 to 4.1:1.
There are some oddballs outside of that range but if I was to do a single-speed car I would shoot for about total of 8:1. For this car running it through the manual trans that would be leaving it permanently in 2nd.
I think fitting an auto with this motor sans the torque converter may be a good option. Solenoid control is the easy part for me, lets just concentrate on mechanical here. I only need a single speed reduction, but 2 or 3 speeds would be nice. Lightweight/compact would be best, something without a bunch of clutches and extra fancy stuff. I'm thinking if it's like a planetary where the second speed locks the sun for basic 2-speed (like a cordless drill) that would be the most simple/efficient. Especially if the default from low pressure from low/no idle would be the low gear, switching to the high gear would always be at speed so no pressure issues.
If it's a FWD trans with integrated diff I can entertain the idea.. would have to be limited slip and I would offset mount it to keep the halfshafts equal length. I'm not too attached to the trunkspace and gas tank area though.. I like the idea of having the whole drive mounted to the rear subframe. Nice thing about batteries is you can balance out almost anything. It would have to be the perfect trans though, this thing looks like it's built for hybrid action so keeping RWD config leaves me the option of stacking another motor in front of it.
No matter what the choice, the input side will most likely get some custom welded part to interface the motor instead of torque converter, just knowing a good starting point is something that someone who's pulled apart several different transmissions would be better qualified to answer than me.
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Thanks for any input.. this one is gonna take some work. I should physically have it in my possession soon, 1st thing I need to figure out, aside from making sure it isn't a 75lb paperweight, is where exactly the oil goes in/out.. if it's feed lines or totally enclosed/submersed.
I don't want to get sidetracked debating man vs auto in general, but as it applies to my particular situation I will consider all options.
My situation is a little bit unusual. Please take a quick look at this motor and attached pics:
http://www.remyinc.com/docs/HVH250R4.pdf
I picked up an engineering lab prototype off ebay which seems very similar to the HVH250. It differs in looks in that there is a hollow shaft, splined on the inside and on the outside there is a helical gear. Looks like it should plug into a planetary arrangement. I'm thinking that this may be one of the motors from Chrysler's 2 motor transmission project. Even if it doesn't end up with as much gusto, on both accounts it appears that it is intended to be filled or totally submersed in ATF. This oil is also used for cooling, I do not yet know if it's self pumping or if I need an aux pump to push ATF through it. But it is a "special needs" motor.
This is going on a RWD car (1981 bmw 633).
My original plan was to fit the motor straight to the differential, but that was before I got this thing with it's ATF needs and the available ratios are kind of low. I would prefer to maintain stock diff to keep my final drive ratio options open, typically in the range of 2.73:1 to 4.1:1.
There are some oddballs outside of that range but if I was to do a single-speed car I would shoot for about total of 8:1. For this car running it through the manual trans that would be leaving it permanently in 2nd.
I think fitting an auto with this motor sans the torque converter may be a good option. Solenoid control is the easy part for me, lets just concentrate on mechanical here. I only need a single speed reduction, but 2 or 3 speeds would be nice. Lightweight/compact would be best, something without a bunch of clutches and extra fancy stuff. I'm thinking if it's like a planetary where the second speed locks the sun for basic 2-speed (like a cordless drill) that would be the most simple/efficient. Especially if the default from low pressure from low/no idle would be the low gear, switching to the high gear would always be at speed so no pressure issues.
If it's a FWD trans with integrated diff I can entertain the idea.. would have to be limited slip and I would offset mount it to keep the halfshafts equal length. I'm not too attached to the trunkspace and gas tank area though.. I like the idea of having the whole drive mounted to the rear subframe. Nice thing about batteries is you can balance out almost anything. It would have to be the perfect trans though, this thing looks like it's built for hybrid action so keeping RWD config leaves me the option of stacking another motor in front of it.
No matter what the choice, the input side will most likely get some custom welded part to interface the motor instead of torque converter, just knowing a good starting point is something that someone who's pulled apart several different transmissions would be better qualified to answer than me.
Thanks for any input.. this one is gonna take some work. I should physically have it in my possession soon, 1st thing I need to figure out, aside from making sure it isn't a 75lb paperweight, is where exactly the oil goes in/out.. if it's feed lines or totally enclosed/submersed.
