Resolved [RESOLVED] How does AWD work? [Merged 9-7] torque split division slip drive

[turboawd1992]

Just always wondered, does anyone know how much power a 1g AWD sends to the front/ rear wheels?

 

[steve]

It's 50/50. See page 21-9 of the 1G tech manual.

https://www.dsmtuners.com/threads/1g-dsm-1990-technical-information-manual.517385/

Steve

 

[turboawd1992]

thanx guys, I'll just assume the 50/50 is correct.

 

[ItsStockOfficer]

Ok, when someone can explain how a viscous limited slip center differential can do anything OTHER THEN a 50/50 split I'll stop calling you all idiots. When you launch it acts like an open diff and sends power where its easiest to go, then it heats up and locks.

 

[2-0turbo]

To my knowledge, the only way you could get anything other than 50/50 is with either a) computer controlled lockup or b) some type of slipper clutch that will only transmit XX ft-lbs of torque. Of course, as you add power (more boost, upgrades, etc), your split would change.

 

[steve]

, perhaps you should correct all your grammar and spelling errors before calling others idiots.

I believe from what I've read, one way other cars achieve torque splits other than 50/50 is by difference in the front and rear gear ratios while holding the speed differences at the VCU to a minimum. 2-0turbo has mentioned a couple of other ways.

Steve

 

[igs]

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[steve]

More from the manual. You'll see that the normal distribution is 50:50 but that changes as wheels turn at different speeds and the VCU tries to equalize the differential speeds.

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The VCU is also capable of locking.

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Steve

 

[turboawd1992]

Wow, thats a lot more than I really wanted to know. So, in general it's almost 50:50. I think you guys can all stop arguing over it now. Steve and IGS just made their case pretty solidly.

 

[Ktreece777]

Is it full time or is it rear wheel drive till it starts slipping?

 

[Spln_Hrd]

full time
sends about 60% of power to front wheels and 40 to rear
unless u break a center diff like me then u can get all to the front, all to the rear, or none to either, or u can get like 60 to the rear and 40 to the front, kinda an interesting part

 

[Ktreece777]

So how would you get 60 to the rear and 40 to the front... or is it if it starts going out... you cant change it can you

 

[98RedGs]

Originally posted by Ktreece777
So how would you get 60 to the rear and 40 to the front... or is it if it starts going out... you cant change it can you

MachV sells a vicious couplin eliminator that you can use so you can turn the car to a front wheel drive. But I dont think they sell anything else as far as to make it an even distrubition.

 

[Spln_Hrd]

u can change a center diff, i am waiting for a rebuild kit(gets here friday) and i am just estimating on percents, there isn't anywhere to find them out here in nebraska

 

[Defiant]

Full-time, 50/50 split. Gearing front and rear is the same, and it's transferred through viscous couplings. If a tire spins, the coupling locks up (real fast).

It's one of the few cars to have an even power split.

It's also the only right way to build AWD, until you get into the (better and) expensive _real_ Hummer.

 

[boostin91]

There is no preset split such as 40-60.

All that happens is that power follows the path of least resistance in the center differential and if either the front or rears lose traction the viscous coupler transfers power to the wheels that are aren't spinning.

It is very easy to see on a diagram, the viscous coupler joins two shafts, one that goes to the rear diff (after it goes through the transfercase) and one that goes to the front diff. If either of these shafts spins at a different rate the viscous coupler is turned. When the viscous coupler the momentum of fluid inside is used to "try" to join the two shafts together.

This is how power is transferred to to wheels with traction. I'm not great at explaining this, but check out howstuffworks.com they have some good diagrams that show how diffs, viscous couplers, and X-Cases work.

 

[Spln_Hrd]

sorry if i am a moron and i am wrong, but i think u can get differant power distributions, otherwise the skylines wouldn't be able to change the power distribustion by computer. I think they make a kit so you can control it manually (saw it on the skyline in the 2002 scc ultimate street car challenge).
please don't jump up my a$$ if i am wrong.

There trannies have some alien special technology in them that i do not know about, but i HEARD awd dsms have 60/40 power split front/rear

 

[boostin91]

Spln_Hrd, I've heard that same 40-60 split comment before too, but I think it is just plain wrong.

Our cars don't have "presets", we have a center differential that is attached to a viscous coupler, which transfers power to the wheels that are not spinning. There is a free technical book floating around on the net, it has good pictures and info on this stuff, anybody got a link?

I think your right about skylines having controllable presets, don't know how they do it though.

 

[TheTSiGuy]

I was curious as to if my awd was working correctly. The other night in the rain i launched and floored it coming off of a stoplight. The result was that my backend started to ever so slightly slide out, but then it corrected itself. is that how its supposed to work?

 

[Spln_Hrd]

btw i know how everything looks, i pulled my center diff out yesterday, i should take a pic and show u how much it is thrashed, i still don't understand how it works though but i know how it looks and the viscous coupling,
what ever the distribution is who cares?
i took a wrx outa the hole and that thing had way more power than me(i got smoked) so it must be pretty good

 

[boostin91]

I did a google search on skylines center diffs. they have an incredible system. Apparently instead of using a viscous coupler they have multiple clutches that engage the front to a varying degree. Sensors such as throttle position, accleration, and speed sensors control the degree to which these clutches lock up. So it sounds like they can be programmed to any split that is desired.

 

[CowPimp]

I have also heard the 50/50 power split is what our cars have. I think 50/50 is a good split for our cars. I would say 40/60 F/R is better, but our cars are noseheavy.

 

[Spln_Hrd]

i liked my car the most as 0/100 f/r cuz i could do wicked burnouts and get sidewayz all the way through second when i was trying to go strait plus i noticed a huge diff in top end, but then it broke and i had no wheel drive, it was on my birthday, which made it worse

 

[Ktreece777]

So does anyone actually know if its 60/40 or 50/50 or ?

 

[Spln_Hrd]

sounds like the vote is for 50/50, i don't KNOW for sure though, either way if u get an awd u will be happy with the launch, i have been in 12 second awd dsms that barely spin the tires in first gear, i would say thats good enough for me