Has anyone changed an IRS diff ratio?

Casper · 24-12-2005, 09:09 AM

Just out of curiosity, has anyone on the forums got an IRS setup with shorter gears than 3.45's in them? Any 3.73's or 3.9's?
I know the live axle has had it done heaps of times but I've yet to come across an IRS setup with these gearings.

T3man · 24-12-2005, 09:33 AM

I have considered going the other way with mine as first is a bit short. Only problem is that fifth is geared for about 300km/h as it is now, so any taller would be a problem at that end. What I really need is a gear in between fourth and fifth ...

However, to answer your Q I know Mal Woods has done a couple of cars with 3.73. But I don't know if they are people from this site. I know they have also done a couple of BAs with 3.73 but 3.91 is not yet available for the BA diffs.

wild6 · 24-12-2005, 10:42 AM

ive got 3.9's in my au xr8 and ive had no problems managed to get a 13.9 out of it so it must have made some improvement

LUXO_8 · 24-12-2005, 11:04 AM

Quote:

Originally Posted by wild6

ive got 3.9's in my au xr8 and ive had no problems managed to get a 13.9 out of it so it must have made some improvement

how much was it to have the gears put into the IRS? are they the same gears as used in a live axle diff???

Casper · 24-12-2005, 11:09 AM

Quote:

Originally Posted by MADNC_8

how much was it to have the gears put into the IRS? are they the same gears as used in a live axle diff???

I've been quoted around $1650 for a full rebuild including new diff gears on mine. As for the actual gears, I believe they are different to the live axle ones from what I've been told..

buickman · 24-12-2005, 01:29 PM

Most places charge about $1,500 to change & rebuild the Borg warner diff. So that price would be the norm

TCK-098 · 24-12-2005, 05:26 PM

To get mine diff done IRS currently 3.45 open wheeler $750 to change over to L.S.D and about $1400 to go to a 3.9 L.S.D centre.

Hope that helps

Cespenar · 04-01-2006, 07:17 PM

I have bought a Max Ellery's workshop manual for the AU's and it states that "once the differential has been removed from the carrier it is identical to the conventional beam axle carrier. Hope this helps.

LOWAU · 04-01-2006, 09:51 PM

Quote:

Originally Posted by Cespenar

I have bought a Max Ellery's workshop manual for the AU's and it states that "once the differential has been removed from the carrier it is identical to the conventional beam axle carrier. Hope this helps.

So if I was to get LSD center including gears from a IRS it would fit in a live axle diff?
I need this cleared as I am on the hunt for a cheap stoko LSD diff for my car and XR6 HP LSD diffs are hard to find, but there is a few IRS LSDs around.

Casper- my brother (SIKSIX) got his diff converted from SS to LSD with new cones and 3.7s for around $1000, but it is a live axle so maybe it doesn't help you much,

wild6 · 05-01-2006, 08:02 PM

i got mine rebuilt and gears changed to 3.9s for $1350 i think its bout $700 to just change the gears

X ORSMXR · 05-01-2006, 09:38 PM

Mate give Chris a Call at Blue Power racing as he does all in house work ie

iff gears and gearbox work and do a very good job...

Lightning Strike GT · 05-01-2006, 10:17 PM

Give grunter (moderator on the XR6 & XR8 club of QLD section) a PM as he had his AU2 XR8 done at Mal Woods about 2 years ago

Casper · 05-01-2006, 10:26 PM

Oh, I know it can be done, I also have quotes and have already worked out the details, I was just curious to know if anyone had already done it to an IRS setup and what it was like.