[nailer335]

All I can do is speculate based on how my car "feels" but I think this really wouldnt be of practical benefit until 60-70mph, or the start of 3rd gear. 1st and 2nd gear disappear in 3.x seconds anyways and you're already in 3rd at that point so...

Just a nitty gritty detail. Depending on Terrys schedule next Month and how worth it this is to him and the xi crowd, I could probably get him my car to do this with. It obviously comes down to ROI for Terry. How many of us would actually pay for this if he were able to come up with a solution? What I'm asking I guess is will this be worth it for a) me to take the risk on my car b) him to invest the time?

[shonuff]

Originally Posted by Doyle

Also, the TC opens 100% at 112mph, not 70.

Doyle knows his stuff. I'm hoping he will chime in and give you the proof/testing done behind this 100mph RWD statement.

As for ROI, I dont see why a XI owner would not want this feature!!

[itsmeek]

Heck yes- trick the awd system into thinking you're going 70 or 100. Slightly increased fuel economy and BURNOUTS.

Nailer- I'd imagine that this could be done with existing JB4 and cable. Much like Cobb who adds new features every few months to their tunes.

[Doyle]

Originally Posted by shonuff

Doyle knows his stuff. I'm hoping he will chime in and give you the proof/testing done behind this 100mph RWD statement.

As for ROI, I dont see why a XI owner would not want this feature!!

The 112mph number comes from an internal BMW marketing document. It is somewhere in this thread:

http://www.e90post.com/forums/showth...&highlight=rwd

I try to make it a point to speak in fact and not internet rumors!

[pits200]

Wouldn't you be able to tell when dynoing the car? Aren't must pulls done in 3rd gear which will take you into 100mph territory.

[itsmeek]

That's the best way to find out, put it on a 4 wheel dyno and see when the front wheels disengage.

[amclint]

I just did a dyno recently, top of 4th gear so ~130mph. At the initial start the front wheels did nothing for a few seconds (ie, < 5 mph) but at the higher speeds the front wheels never seemed to slow.

On the contrary, when the dyno operator let off, the front and rear wheels seemed to dis-engage on the dyno the same way. I don't know of any way to tell if the fronts had power or not over 100mph, but from 112-130mph if there was no power from the fronts you would think that the front roller would be spinning slower. I suspect the only way to tell would be to read the power levels from each dyno drum, that would tell you what the front drum had going to it. I will be going back to this dyno when I get my FMIC and DP on, I'll talk to the operator about what he may or may not have in his software to show each drum's details.

[Doyle]

^+1

I wouldn't trust visual clues as there will still be alot of inertia left in the front roller and changes in speed may or may not be seen. Especially since I bet there is at most a couple seconds between hitting "112", hitting the rev-limiter, and then coming back down to "112".

[Kalud]

From those internal documents its also noted that:

Operation on brake test rigs
Selector lever position N must be engaged on vehicles with xDrive and automatic gearbox for testing on brake test rigs. In this setting, the transfer case clutch remains open and the vehicle cannot be pulled out of the test rig.

In the case of vehicles with xDrive and manual gearbox, the accelerator must not be pressed when the vehicle is on the test rig to ensure the transfer case clutch is not closed.

"Closed" means engaged, driving the front, "open" means dis-engaged, rwd operation only.

[henry418]

So... did anyone try tracking in RWD mode? Or even an autox event..

[DXL007]

Subscribed

[ColdTestament]

Id love to have this option. To the poster that would take your car to Terry! Please do. I'm sure it would be a great marketing for him.

[DannyZRC]

Originally Posted by DannyZRC

On many of these clutch-coupled 4wd systems the parking brake signal will de-energize the transfer clutch.

Has anyone verified this as not being the case for the xdrive?

Anyone try this? pulling the parking brake up 1 click to close the switch?

Put it into a gravel parking lot, parking brake on one click so the light is illuminated, and test.

[Quebequer]

Subscribed.
Very interested in that feature!!!

[ColdTestament]

hey team XI - any pics of your cars? i'd be curious to see.

[Doyle]

Originally Posted by DannyZRC

Anyone try this? pulling the parking brake up 1 click to close the switch?

Put it into a gravel parking lot, parking brake on one click so the light is illuminated, and test.

Yeah, I tried it. No, it didn't work.

[DannyZRC]

Originally Posted by Doyle

Yeah, I tried it. No, it didn't work.

Well done, thanks for Data

[Mgrant]

suscribed !!!
That would definetly help make my up my mind between buying an Xi or I

[itsmeek]

C'mon CALI guys- get a car over to Terry so he can set this up for us. Slackers!

[jcarv20s]

I have an XI that I'd let Terry try to write some code to make it run RWD.....If you get me a job out in Cali haha.

[ExpensiveTaste]

Originally Posted by jcarv20s

I have an XI that I'd let Terry try to write some code to make it run RWD.....If you get me a job out in Cali haha.

Justin, nobody's going to pay you to be a women's lingerie model in Cali...I'm pretty sure Arnold Schwartzenegger would kick you in the testes and send you back to CT

[TeroRider]

bump! Guys, any development??
There were 2 of you that tried a system by yourself.