PDA

View Full Version : Dyno question


mpampis_
23-02-12, 06:29
Hello guys, does anyone tried to dyno a q4, or even tried to chiptuning in a 2wd dyno? If yes in which axel? Thank you
Steve Webb
23-02-12, 10:07
Hello guys, does anyone tried to dyno a q4, or even tried to chiptuning in a 2wd dyno? If yes in which axel? Thank you

Mine was done on a 4wd dyno, running a Q4 on a 2wd dyno, even with rollers under the other wheels is going to put the transmission under a lot of stress and the results you get from it would be pretty unpredictable I would of thought.
Suzumushi
23-02-12, 10:22
Mine was done on a 4wd dyno, running a Q4 on a 2wd dyno, even with rollers under the other wheels is going to put the transmission under a lot of stress and the results you get from it would be pretty unpredictable I would of thought.

But, in theory, if You can't get access to 4wd dyno, it's possible to disconnect rear diff and measure the car like fwd...
but it's only a theory.

best regards
Steve Webb
23-02-12, 10:41
But, in theory, if You can't get access to 4wd dyno, it's possible to disconnect rear diff and measure the car like fwd...
but it's only a theory.

best regards

This is where all the problems will start coming from, the car will still be trying to split the torque 47/53 f/r but as the rear wheels won't have any resistance the center diff (VC) will just lock solid, and all of the torque will go to the front wheels putting a lot more power and torque through the front transmission than it was designed to handle ,and putting an awful lot of strain on the VC.

Even with a standard car I would expect something expensive to go bang.

Thats my thinking on the process, but if someone wants to try, go ahead, just make sure you record the dyno run on camera !! :thumb:
mpampis_
23-02-12, 11:32
As I said I don't care to measure the hp and torque. This I will do it normally on 4wd dyno. They want 100euro per hour if you want to make the chip tuning, so I will need 2 hours it is 200 euro. I can do that for free but the dyno is 2wd and the only I care about is
1. If this will make a problem to the diffs
2. If I will have enough load to boost the turbo
Steve Webb
23-02-12, 18:30
Sorry I didn't realise you were just going to use the dyno to do an initial setup. You might get away with it, but personally I woundn't risk it.