Are 2 wheel dynos for AWD a nono.....?

**volvokid** · Tuesday 28th February 2012, 10:16

Very intresting, i read on here some one wanted to use a 2 wheel dyno for there S60R and they got adviced it was ok, read this and you will see its not, dunno what im gonna do for MOTs. http://forums.t5d5.org/topic/18420-s..._fromsearch__1

**Jimmie** · Tuesday 28th February 2012, 10:27

Dont worry kid they will have the proper kit.
I wonder who is going to say something negative on this subject?

**volvokid** · Tuesday 28th February 2012, 11:39

Originally Posted by Jimmie

Dont worry kid they will have the proper kit.
I wonder who is going to say something negative on this subject?

Called the garage and they said the same :^)

**s_cowen** · Tuesday 28th February 2012, 12:48

Not good at all, makes MOT times even more stressful than they already are!

**Pauld** · Tuesday 28th February 2012, 15:38

All 4x4's have the same problem at MOT time.

My local garage has always taken mine down the road for a drive to check the brakes.

On one occasion the tester came back white having done an emergency stop in a Land Rover defender with 37" tyres.

Gosh that s a dangerous car, or something like that came out of his mouth

**Santa** · Tuesday 28th February 2012, 18:04

Haldex used to have a document available before the borg warner merger that went on about 2wd dynos. One of the things mentioned was around 5% of power (or whatever) is always sent to the back for calibration reasons.

**sprintman** · Tuesday 28th February 2012, 23:42

It used to be that MOT test centres would have a 'Tapley' meter or something similar for testing 4WD's. The meter has a heavy base and sits on the floor of the car, the tester drives down the road and brakes fairly hard [hopefully in a safe place!], and the meter indicates the overall braking efficiency. I'm not an MOT tester, so I don't know how it's done these days, the guy that tested my V70 AWD recently just drove the car through the workshop and braked! So how they can test the individual efficiency of the brakes as they do for 2WD's is beyond me.

**Santa** · Wednesday 29th February 2012, 07:39

Guys can we keep this on topic and not accuse or insult each other. (I'm sure the original poster hasn't got this intention). There is a lot of information out there regarding the suitability of running Haldex equiped AWD cars on 2WD drive dynos. Some information shows its fine, some shows it not.

On the braking under MOT tests this is the first time I've considered this because of this post.

Ultimately its up to individual car owners to decide if they wish to use 2WD dynos, use the brake testing equipment at MOT stations or run there cars with broken collar/bevel gears but they should be able to make this decision based on balanced information!

In summary and an owner of a haldex equiped car I'm interested in seeing a balanced discussion of the for and against. (Especially for, as theres a lot of information out there with supporting reasons as to why its not ok). What I'm not interested in is accusations and insults. (If anyone wants to report an issue you know how to PM me).

**hamish** · Wednesday 29th February 2012, 10:14

Originally Posted by volvokid

Very intresting, i read on here some one wanted to use a 2 wheel dyno for there S60R and they got adviced it was ok, read this and you will see its not, dunno what im gonna do for MOTs. http://forums.t5d5.org/topic/18420-s..._fromsearch__1

Volvokid,

It is a well known fact that you should NOT run Haldex cars on Unlinked 4WD Dynos. With regards the MOT EVERY single station has a Decelerometer and will use it where necessary.

Regards.

**stribo** · Wednesday 29th February 2012, 10:33

Very useful post, I hadn't even thought about the MOT brake test until this thread.

**Santa** · Thursday 1st March 2012, 08:15

Please note this is an edited copy of the original thread. If you wish for one of your posts to be removed please contact a moderator.

Please refer to my post 8. Please keep this thread on topic and balanced!

**volvokid** · Thursday 1st March 2012, 10:50

Im not writing this to stir it up again, i have spoke to my garage regarding mots and he said he wouldnt run my car on the brake tester. As a garage what is your take on this and what do you guys use for high speed dyno runs? Is it 2wd or 4?

**volvokid** · Thursday 1st March 2012, 10:52

Nats wheres ur post went????

**Santa** · Thursday 1st March 2012, 11:16

Guys ive had to close this thread. The amount of rule breaking alone is causing a massive administration burden

This could have been an informative thread where "specialiats" could have made there case with supporting facts. Instead its turned into a joke.

We now have to work out all the rules that have been casually broken.

**Santa** · Thursday 1st March 2012, 11:19

Further to my last post. To fill the void we are going to find some independant specialists and contact the manafacturers for information. Once we have the results we will post here.