Allwheel Drive Omni GLH SRT4

[cj011]

So lets say that you were able to get the correct gear ratios, with the diff always putting power to the rear tires will that cause premature wear?

[Force Fed Mopar]

Only from your right foot

[Reaper1]

So lets say that you were able to get the correct gear ratios, with the diff always putting power to the rear tires will that cause premature wear?

Premature wear of what, exactly?

[cj011]

I was under the impression that there are vacuum solenoids for the cable speedo rear that control whether the rear is engaged or not. That is why I am asking. If the rear distribution of power is based on slip of the front tires, then my question is pointless. If my understanding(which could be wrong) is correct I was leaning towards diff issues due to the system always technically being engaged. If that is not the case, then that would make things alot easier since the only concern would be to match the front and rear ratios.

[86Shelby]

The minivan setup uses an overrunning clutch that engages when the front differential is turning faster than the rear differential. There is an ever so slight difference in the front & rear differential ratios that make the setup FWD all the time unless the front tires lose traction, then the rear tires recieve power through that overrunning clutch as well. The overrunning clutch only allows power to be sent one-way through it. I don't recall what the exact gear ratios are, but for example the front could be 3.5:1 and the rear could be 3.55:1. In normal driving the driveshaft between the front & rear is turning faster than the front differential due to the .05:1 difference in the ratios which causes the overrunning clutch to disengage. Once the front tires start spinning the overrunning clutch engages because the speed of front differential is more than the .05:1 difference in the ratios, which then sends power back to the rear tires through the rest of the AWD setup. No vaccuum solenoids or fancy viscous differentials are used.

[Reaper1]

There IS a viscous coupler, a 2-way bearing (overrunning clutch), and a mechanical coupler that is actuated by vacuum (for the older set-ups).

The coupler is there is take up the difference in the rotational rpm from the front and rear diffs. After a certain % of slippage the coupler will "lock" and send more power to the rear.

The overrunning clutch is there for when there is no power being applied to the driveline and it allows the rear tires to then rotate at a different rpm without locking up the viscous coupler. It is a 2-way because this action also happens in reverse.

The mechanical actuator is for reverse. When reverse is selected, the only way to get AWD in reverse is to directly drive the input to the rear diff as the viscous coupler will not work. So, the mechanical coupler forces AWD in reverse.

[cj011]

great info guys. So basically if the rear gearing is the same as stock, it wouldn't interfere with normal operation of the coupler regardless of what car its from?

[Aries_Turbo]

great info guys. So basically if the rear gearing is the same as stock, it wouldn't interfere with normal operation of the coupler regardless of what car its from?

the coupler (and all the other associated parts) are integral to the rear differential. adapting certain pieces to another rear differential would involve significant machining and custom fabrication.

Brian

[RoadWarrior222]

Basically the answer is you can fit anything to anything with a sufficiently well equipped machine shop. Sherman tank tracks on a minivan, no problem!

[86Shelby]

My bad, you're correct Reaper1. Thanks for the clarification!

[Reaper1]

great info guys. So basically if the rear gearing is the same as stock, it wouldn't interfere with normal operation of the coupler regardless of what car its from?

Like Brian said, you would have to adapt the parts in front of the rear diff in order to make it work (like stock). However, Ondonti (Brent) is wanting to run a solid rear axle from another application and get the gear ratios right with tire size and gearing. This will prevent driveline binding, but in rear world application it could potentially cause premature wear.

My bad, you're correct Reaper1. Thanks for the clarification!

NP. I hope I didn't come across harsh. The intarwebz has a bad way of making things sound offensive sometimes.

[OmniLuvr]

I could be dead wrong on this and I am just throwing an idea out there, why not just use the complete rear setup from on eclipse awd donor car?

ive wanted to do that, i think the first gen eclipse is a complete rear subframe. the diff, axles, arms all mounted to a subframe that can be removed by 4 or 6 bolts.

im glad i learned a little more on how the setup works now.

my plan was to use the complete eclipse drivetrain, but figuring out how to flip the engine to the drivers side seamed like a bigger problem then i wanted to deal with. not sure if the evo engine and trans would work (they are flipped like ours)...

anyways, subscribed for updates...

[markassbauer]

Any info on where and what this Omni has been up to? I see from the YouTube videos the OP passed away
just curious...

[Vigo]

This is more recent: http://www.turbo-mopar.com/forums/sh...rt4-needs-help

[663csx-t]

[QUOTE=markassbauer;1109258]Any info on where and what this Omni has been up to? I see from the YouTube videos the OP passed away

The omni is still around.
A lil up date turbo was rebuilt it was smoking big time.
Now I think I may have to replace vaule guide seals it's still smokes but not nearly as much. I also have to have to play with the power steering pully. When I replaced the pully I put it on to far. Now have
to pull it out a Lil bit because the belt is not line up correctly. Makeing the belt to slip off. When the slips off it messy up timing belt. Do to haveing twin babies I'm unable to get the time to work on it. The omni is soo close to being back on the streets. It's hard for me to not work on it. I also had to work part time for about 8 months so the funds was not there.i hope soon it will be back out eating mustangs

[BadAssPerformance]

Good update, thanks for sharing! For smoking, make sure the turbo oil drain is flowing well, any backup in the turbo can smoke.

[mike radowski]

Keep me in mind! I have a mint 60k mile red GLH now but I would love to get my hands on this machine!

[663csx-t]

Keep me in mind! I have a mint 60k mile red GLH now but I would love to get my hands on this machine!

Mike you will never stop trying lol

[mike radowski]

Nope! I'll shoot you an email about my recent purchase.

[Turbo Joe]

Nope! I'll shoot you an email about my recent purchase.

holy smokes !! MIke ! good to see your still messing with these cheap cars not just bmw's... is there another 10 sec. TD coming together?