Every now and again I pull my AWD project out of the dust of my brain and take another look at it.
I'm trying to come up with a way to make an AWD car/rod. Haven't decided yet on the vehicle as that might be driven by the packaging.
Anyhow, I've settled on independent front and rear suspensions which will essentially fix all the drivetrain components in the chassis so I don't have to worry about accomodating the drivetrain moving as a live rear axle would move up and down with the suspension.
One of the things I'm seriously considering then, is mounting the transfer case in front of the rear differential, instead of directly behind the transmission. That way, the packaging that large assembly will most likely affect the rear seat area instead of the front seat area.
A real problem I've been wrestling with is how to get the front driveshaft up to the front differential from the transfer case.
I have a Sierra pickup with 4wd. I'm assuming that any AWD transfer case I'll be using will have roughly the same dimensions. In the pickup, the front driveshaft runs roughly right under the accelerator pedal. I'd really hate to have to expand the driveshaft hump that far over to encroach on the driver (or front seat passenger, if I reversed it) footwell.
So, one thing I thought about is perhaps using a system of driveshafts, universals and bearing carriers.
I figured I could have one driveshaft that angled inward from the rear transfer case towards the main driveshaft off the transmission. That would lead to a straight driveshaft, parallel to the main, and held in place by carrier bearings front and back. That would run right up to where the main driveshaft enters the transmission, where another driveshaft would angle off to the front differential.
The intermediate driveshaft would always be parallel with the main. However, the front and back sections of the multi-section driveshaft going to the front diff would have two sections that would always be angled.
Just from experience, it seems most driveshafts with universals are set up so they are straight at ride hight, and only operate at angles when the suspension moves.
So, I'm wondering if it is feasible to have driveshafts that operate at a fixed angle all the time?
Is there some maximum recommended angle that can be used without problems?
Would CV joints be better than universal joints in this sort of setup?
Any other ideas?