That's pretty cool being able to swap between the two types of drive. I live up in a snow state too, so I feel your pain. Keep up the creativity, and wrenching.
Haha thanksAwesome post man :clap:
This is really the last remaining issue to tackle to make this a viable swap so I'm very interested as well. I have other priorities right now, but sometime soon I'd like to look into whether we can just code the DSC unit we have using NCS Expert instead of swapping it with one from an E39. There's a thread where someone with a ZHP was able turn off the system that emulates an LSD using the brakes. I know that's a different unit entirely, but we may have similar options.Any electronics guys out there? I've been researching a work-around for the single stage xi DSC. I found a thread that seems to confirm the later e39 Bosch 5.7 units will bolt right in with a few swapped pins in the connector. I'm wondering if the new unit will bring fully disable-able DSC to the car, or if coding it will force it to act like a normal xi unit.
I'd be willing to guinea pig if we can get some definitive info on the coding. I recently did my own EU2 tune. The fact that rwd e39 cars shared the same DSC unit makes me hopeful. I'm capable, I just don't have enough confidence in my understanding of coding to dive in without some expert guidance.This is really the last remaining issue to tackle to make this a viable swap so I'm very interested as well. I have other priorities right now, but sometime soon I'd like to look into whether we can just code the DSC unit we have using NCS Expert instead of swapping it with one from an E39. There's a thread where someone with a ZHP was able turn off the system that emulates an LSD using the brakes. I know that's a different unit entirely, but we may have similar options.
If we can turn off our DSC units' longitudinal differential-lock function (braking the slipping axle as previously discussed), then this mod can be done without any risk to drivetrain components.
I've been working on a little side project and I've finally made enough progress to post about it here. I picked up a junkyard transfer case and welded up the planetary gearset inside. Not the prettiest welds, but there are more than enough throughout, and the final re-sealed diff spun smooth as new. With a locked center diff, I can run without a front driveshaft and enjoy the RWD. I swapped it in this afternoon and had a very successful ride home. No noise or vibrations way beyond highway cruising speed plus all the perks of rwd (noticeable power bump, oversteer under throttle, slip when I wanted it). DSC wasn't too happy with me when I did mess around, even with it "disabled", but I risked a few clutch dumps in the rain and got plenty of standing wheelspin. I'm going to unplug the unit soon and see what it can really do. The plan for now is to leave the front diff and axles in, the idea being to swap the old transfer case back when I put my snow tires on. But you never know...
Back to 4wd just in time for the first snow day of the year. I put about 10k on the car in rwd with the front diff and axles still in place. No noise or vibrations on the ride home. I'd say this first season was a success.
What happens if you just remove the front drive shaft without welding anything. In the real world, this would be the equivalent of having the front tires on ice, and the rear on pavement.
Totally understandable, if you're looking for your traditional ring/pinion/spider gear setup. A planetary gearset actually acts in the same way. In that pdf you found, look at the diagram of the gearset. The three little "planets" take the place of the spider gears. Power is applied to the carrier that houses them, much like the diff carrier in the rear. In an ideal situation (no differential action), the planets themselves don't spin (like spiders), and the whole sun/planet/ring unit spins locked in unison. Equal output speed to both front and rear, same as equal output speed under normal conditions in the rear. As differential action is naturally induced by the changes in wheel speed front-to-rear (in turns, during loss of traction), the planets begin to spin to allow a speed differential between the sun (front output) and ring (rear output). Same concept in the rear; as one wheel accelerates beyond the other, the spiders provide differential action between the two sides. And just like in an open rear, without any clutches or other gears to limit slip, the planetary gearset is more than capable of providing full differential action and sending 200% speed to the bare front output shaft vs. 0% speed to the still-connected rear.Looking at drawings of this transfer case, it doesn't resemble a differential at all.
My children, unplug abs brain in drug bin. remove front half shaft, remove tranny, tcase, add a rwd trans, plus this custom trans mount. This custom trans mount is for sale, uses all oem mounting locations on xi's, direct swap. With this custom mount, you can make your xi rwd. I sold my old rwd swap xi, working on a new project. GL, if you guys have any questions lmk. To the guy above me, yes if you have a manual tc laying around you have that small shaft.