Selectable Trans/T-Case Questions

[TSiWarrior]

I've got the selectable trans/t-case combo. I've been playing arund with it a bit goofing around in FWD mode, etc. I've got a few questions about it tho.

1. Does driving hard (on the gas) in fwd mode damage anything?
2. Can the FWD mode safely handle power?
3. Are these trasmissions more noisy than normal, or is that just mine?
4. If I equip the transmission with some electronics (already have plans layed out) can the tcase and transmission parts properly seperate under power. I.E AWD launch then throw it into FWD. I can understand why FWD to AWD while moving would be near impossible. I've checked the VFAQ about this trans and it looks like it *should* be able to disengage while moving without problems.
5. Is there anything that I should be careful about or take special notice to (different fluid, anything) about these transmissions?

I'm having a good time with my trans so far, it seems to be working good. It's real fun in FWD mode having the AWD gearset Thanks!

 

[SolidBoostTSi]

I've got the selectable trans/t-case combo. I've been playing arund with it a bit goofing around in FWD mode, etc. I've got a few questions about it tho.

1. Does driving hard (on the gas) in fwd mode damage anything?
2. Can the FWD mode safely handle power?
3. Are these trasmissions more noisy than normal, or is that just mine?
4. If I equip the transmission with some electronics (already have plans layed out) can the tcase and transmission parts properly seperate under power. I.E AWD launch then throw it into FWD. I can understand why FWD to AWD while moving would be near impossible. I've checked the VFAQ about this trans and it looks like it *should* be able to disengage while moving without problems.
5. Is there anything that I should be careful about or take special notice to (different fluid, anything) about these transmissions?

I'm having a good time with my trans so far, it seems to be working good. It's real fun in FWD mode having the AWD gearset Thanks!

I have one aswell and as far as going from mechanical to electronic switching, you would have to do some soleniod attaching here and there. Also does your switchable have a front LSD?? because mine does and I didn't know if they all came like that. FWD mode should be able to handle the power except for the fact that you are transfering the power 100% to the front drive wheels I would just treat it like a GST, and face the tracion issues from a dig. keep me posted

 

[GRNDSM]

I have been playing with a switchable transfer case for over 7 years, so I have quite a bit of experience with it.

1. Does driving hard (on the gas) in fwd mode damage anything?

Your tires . As long as you do not get wheelhop,which is easier to experience because of less traction, you should be fine.

2. Can the FWD mode safely handle power?

Yes, FWD is accomplished by making a 4x4, just like a VCE, and then turning off RWD. So it is just as safe as VCE equipped car. But bare in mind that it still has a 4 spider gear center diff, so you can bust it pretty easy. And in FWD mode, your torque is going through the spider gears.

3. Are these trasmissions more noisy than normal, or is that just mine?

It is just you or your particular tranny . There is nothing about that should make them noisier.

4. If I equip the transmission with some electronics (already have plans layed out) can the tcase and transmission parts properly seperate under power. I.E AWD launch then throw it into FWD. I can understand why FWD to AWD while moving would be near impossible. I've checked the VFAQ about this trans and it looks like it *should* be able to disengage while moving without problems.

The problem with solenoids is that they do not like to be seeing 100% duty for a long period of time. Then, you have to decide which mode you want to make as your default. FWD default will give you safer option for FWD dyno testing, but it can ruin your race if it fails. But AWD default can be very dangerous if it fails on a FWD dyno! After much though, I have decided that a mechanical actuator (via a cable) is the best option.

I actually have a system designed and half made, but then I ran out of time/interest in completing it.

5. Is there anything that I should be careful about or take special notice to (different fluid, anything) about these transmissions?

Nope, they are pretty simple. I am actually convinced that switchable transfer case is STRONGER than the US market unit! The tranny is just as weak as any other 90 DSM tranny. They also do not have the good synchros of the 93+ trannies

 

[TSiWarrior]

Anyone know where I could purchase a rebuild kit with upgraded syncros for it?

 

[GRNDSM]

Sure, I just send it to ShepRacing and John figures out all the right parts .

 

[TSiWarrior]

Grndsm,

So you belive the trans has the capaiblity to switch from AWD to FWD while moving? I could build a cable system pretty easily, but I want to make sure it wont destroy things when I switch it.

 

[GRNDSM]

So you belive the trans has the capaiblity to switch from AWD to FWD while moving? I could build a cable system pretty easily, but I want to make sure it wont destroy things when I switch it.

While moving? Sure! While under 400hp+ load? Probably not the best idea.

It is sort of like taking a tranny out of a gear. You can do it while moving, but it is difficult to do while under load.

You could time it that it turns off when you are shifting into 4th. You wouldn't want a 400whp FWD car in 3rd gear anyway .