Ve LSD Diff Information

[Johnjoe]

Ok sorry if this is somewhere else, I'm on my phone and the threads only go up to page 4.

I'm looking into getting a LSD complete diff for my ve sv6 sedan 2010 manual.

Just trying to find some info for it so I can decide if I want it, because the gear ratio for first gear is super high, I think 4. Something, it revs out too quick without having much speed before hitting second.

I assume they have done this for the people that may tow things, but will a higher ratio LSD diff make this worse? Or even just higher ratio in standard single spinner diff if that's possible

Going 3.7 in the diff obviously will give it better acceleration but what I want is for it travel further before needing to change into second.

Right now first gear is pretty much pointless, and second is too low of a ratio to start off in and get a good jump.

So will it be worse? Or will it give quicker acceleration as to not need to worry about the distance travelled before hitting second?

Cheers, John

 

[Customcreations]

Hmmm.
What's the diff ratio at the moment?

 

[Johnjoe]

2.92 for sv6 manual? I think not sure, or a low 3

 

[Customcreations]

2.92 for sv6 manual? I think not sure, or a low 3

Sorry for delay.
Was warching a spun out movie.

"stranger than fiction".
It makes me think of myself

If you want to reach a better speed before changing to second gear and for arguments sake your diff is 2.92:1
You would need to have a change from 2.92:1 - to something with a lower ratio: not higher.
( I don't know what ratios are available lower than 2.92 so don't quote me on the figures)
BUT as in from 2.92 down to 2.52 to give you the jist of it.
Ratio is measured by how many times the tailshaft (2.92X) turns to 1 time the wheel does an exact single turn.
If the tailshaft has to turn 3.08 times to 1 turn of the wheel as mine does in the VS then the distance you travel before changing will be less.
It can kind of seem back to front but if you break it down it becomes easier to realise.
less times the tail shaft turns the further or rather sooner your wheel will reach its 1 revolution.
For now it's the diff your asking about changing.

Sadly to change it in the gearbox would cost you big bucks as you would need to replace the cluster gear and it's likely that the available cluster variations would also change at least 2nd, 3rd, 4th and possibbly 5th. Though 5th should be a removable gear individually due to it being independant from the cluster gear.

 

[Johnjoe]

Yeah that's what I thought, I just was reading alot of posts and how people went to the higher diff and saying it was better but can't imagine how in a manual. Auto would be good with diff change.

I guess I can go bigger wheels ha ha, travel further in one rotation of the tyre. Unless 3.7 diff improves acceleration so much so that you make up the time in the launch.

Good movie by the way

 

[Customcreations]

I went higher profile on the tyres and it completely eliminated wheel slip so now when I take off hard (when it was auto) + the LSD it just bolts with every bit of power straight to the wheels.
It helps heaps to go higher profile not lower as everyone does.
(if you want grip that is)

 

[Fekason]

Hi,

I am assuming that your SV6 is an MY10, i.e. SIDI engined. From MY10, the SV6 manual has been fitted standard with an LSD. It has been optional on autos.

The earlier SV6 had a 2.92 diff ratio, giving around 60, 105 and 166 KPH at max power RPM (6,400) in the first three gears. The SIDI engine diffs are in fact 3.27, and give around 54, 94 and 148 for these gears. A 3.7 final diff ratio would give around 48, 83 and 131.

Thus if you are worrying about running out of first gear too quickly, the 3.7 diff would make it worse.

 

[Johnjoe]

Is this for series 1 sidi aswell? I thought LSD was only standard on hsv models and optional if you wanted it on other models.
I'll have a look at the number printed on it, anyway thanks for that info.

Anyway that brings me back to what I should do then, because going higher is going to give it quicker launch but run out of revs even quicker, so not sure if that will help or be worse. Guess will have to try and see

 

[Fekason]

Is this for series 1 sidi aswell? I thought LSD was only standard on hsv models and optional if you wanted it on other models.
I'll have a look at the number printed on it, anyway thanks for that info.

Anyway that brings me back to what I should do then, because going higher is going to give it quicker launch but run out of revs even quicker, so not sure if that will help or be worse. Guess will have to try and see

I have the MY10 (SIDI) Commodore brochure, and it indicates LSD standard on manual SV6, as does the Series II brochure.

I find the take off more than adequate in my Series II SV6 manual, and have found the gearing much better in normal driving over the MY09 SV6 manual that I had previously.

 

[Johnjoe]

You find first a bit too short? Only because I don't intend to rev it to 6500 everytime before I hit second lol. I go to around 3 or 4k and it's only doing about 25 or something like that so have to change to second, that's pretty much straight away after take off because it gets up there so quick in first.

I find it drops off around 5-5500 anyway if I keep it going, and that's still so soon aswell, whereas other cars can get to higher speeds before needin to go into second so they can get a better run