Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: saintnick on 21 September 2007, 17:04:43

Title: 3.0 V6 diff, can i use in another car?
Post by: saintnick on 21 September 2007, 17:04:43
will i be able to use the diff from a 3.0 V6 on a 2.5 TD using the AR35 box

i know the ratios are slightly different (3.0 v6- 3.90 and the TD is 3.75)

will this cause issues or will diff have to go :-/

cheers peeps.  :y
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: IrmscherKris on 21 September 2007, 17:45:21
As far as I remember, yes it will be ok.

Did you look in to the FBW thing yet?  :y
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: Dazzler on 21 September 2007, 18:32:01
My limited understanding is that it will fit but if you change the ratios you will also change the speedo reading accuracy :-/
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: Kevin Wood on 21 September 2007, 18:44:04
My understanding is that the speedo readings come from the ABS sensors which are after the diff so they shouldn't be affected.

3.75 to 3.90 will make the gear ratios a bit shorter. It will give a bit more acceleration in the in the lower gears but it could run out of revs at higher speeds. Having said that, the difference iat 5,000 RPM is only an additional 200 rpm between these two ratios. I guess the auto box ECU could be confused by the road speed not corresponding to what the gearbox ECU expects or it could be based solely on engine RPM which shouldn't make too much difference.

If you know how RPM relates to speed with the original diff take a few spot readings and multiply them by 3.90/3.75 and see if you could live with the results.

Kevin
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: Dazzler on 21 September 2007, 19:14:18
I thought the speed reading for the ABS ECU was taken from the n/s rear wheel ABS sensor :-/ Thus if the wheel is now spinning at a different rpm due to the diff ratio then the readingd will be wrong :-/ Then again i could be completly wrong ::)
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: TheBoy on 21 September 2007, 19:36:40
Quote
I thought the speed reading for the ABS ECU was taken from the n/s rear wheel ABS sensor :-/ Thus if the wheel is now spinning at a different rpm due to the diff ratio then the readingd will be wrong :-/ Then again i could be completly wrong ::)
The rotational speed of the shaft that has the abs sensor will (for a given wheel circumference) will remain the same for a given speed, irrespective of the engine speed, so changing the gear ratios, either at box or at diff will not affect speedo accuracy.
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: Dazzler on 21 September 2007, 19:53:58
Quote
Quote
I thought the speed reading for the ABS ECU was taken from the n/s rear wheel ABS sensor :-/ Thus if the wheel is now spinning at a different rpm due to the diff ratio then the readingd will be wrong :-/ Then again i could be completly wrong ::)
The rotational speed of the shaft that has the abs sensor will (for a given wheel circumference) will remain the same for a given speed, irrespective of the engine speed, so changing the gear ratios, either at box or at diff will not affect speedo accuracy.
It doesn't take much to confuse my little brain. Sorry for misleading on this thread :-[ :-X
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: saintnick on 22 September 2007, 06:30:08
thanks for all the replies, its me being lazy really, if i dont have to change the diff, why make work for myself ;)

i think im taking enough on as it is  ::)

i know, i deserve everything i get! LOL
Title: Re: 3.0 V6 diff, can i use in another car?
Post by: saintnick on 22 September 2007, 06:34:06
Quote
As far as I remember, yes it will be ok.

Did you look in to the FBW thing yet?  :y

im going to attack that on sunday with a bit of luck, the engine is ready to lift out but might not get to do that today  :-[

im assuming it goes from the pedal up to the cruise control buttons then off to ECU so im going to demolish the dash and trace all the wiring and remove it as one piece, then try to attach in other car, that is the only way i can see it working.