Diff Gears Problem

[lacy18]

G'day

I got my first commodore a few months back (Silver 05 SV6) after a stack of saving etc...and have been working my way through different mods. Currently I've had a full exhaust system done, did the two hole airbox mod and put in a k&n air filter.
The issue that I'm havin is that she's pretty slow off the line i.e. my mates vx beats it off the line initially :bang:
After reading through all the posts on here (which were great) I had a look at the diff and it turns out that its got 2.87s. I know that a lot of you guys on here with SV6's have put in 3.46 or 3.73 gears but when I went to find out more I was told that my diff is a 7.5inch and that the higher ratio gears are only made to fit the v8s that have an 8inch diff??
The guy said that I'd need to get an entire new diff $$$$ and i'm just wonderin if this is right or not??
If any of you who have changed your diff gears could let me know how you did it that would be awesome!

Cheers

 

[VT Berlina 07]

do you own a broom? if you do take the stick and shove it up the braindoner's a*s that told you that. you dont need to buy a new diff. you just change the gears inside the diff. if yours is an auto you have to get it calibrated to suit the new ratio. depending on if you want an LSD fitted your looking at around the $1000 mark rebuilt with gears add another $500 for a limo. (this varies from state-state.town-town etc) hope that helps:thumbsup:

 

[lacy18]

Haha thanks for that mate. Its a 5 speed auto and it already has a LSD. Does anyone know of somewhere good in Adelaide where I can get some gears from? Also would it be better to go for 3.46 or 3.73 from your experiences?

Thanks

 

[vy-346]

Haha thanks for that mate. Its a 5 speed auto and it already has a LSD. Does anyone know of somewhere good in Adelaide where I can get some gears from? Also would it be better to go for 3.46 or 3.73 from your experiences?

Thanks

3.46 for sure mate, and be revving at 2400rpm at 110. 3.73 is probly a bit too much for the auto as the gearset in the box is already pretty steep.

 

[commodoreuteboy]

Are the manuals the same as the autos?

 

[Nordy]

The diff ratio is the same in the manuals as the 5-speed autos, the 2.87 ratio. Although when it comes to changing the diff ratio, also keep in mind the gearbox ratios which will differ between the auto n manual

 

[impulsesv6]

if you have the auto you will need to have the speed sender recalibrated.
and maybe the gearbox ,but i think the gearbox is calibrated by the speed sender.

holden or your tuner should be able to do this

 

[lacy18]

So does anyone know where I can buy some new gears from in Adelaide? Or would it be easier to get some second-hand ones off ebay?

 

[StevieP]

second hand ones of ebay or one of the V8 forums....