I want a LSD

[Dezza]

OK ive been wanting to get a lsd for a while now but i know nothing about diffs
I got a 92 manual vpv6 and i want a lsd but i dont know wat a good diff ratio will be for me i want the car to be quick off the line but i dont want to loose too much top end would i just be able to go to a wreakers and get a lsd of a something or its to risky getting something like a diff from the wreakers? im pretty confident i can install it myself as i just hellped a mate put a lsd in his (cough) ed falcon and it didnt look that hard

[gocommygo]

id love to know the same thing lsd's rock

[sircruisealotVS]

about the only place you'll get a decent price lsd for your car is from a wreckers...as for the ratio, 3.45:1 is pretty common.

[Doctor Sodways]

3.45 on a commo should be pretty good to launch of the line with, a 3.7 will go better again but you would virtually no first gear and top end speed, 3.45 is the most common performance diff untill you get to drag cars, current SS' have a 3.45 and tickford falcons too, an early falcon up to EF(i think) diff centre should fit as far as i know as well

[Dezza]

how much would i be looking at price wise ,
would 3.45's be good in a v6 i dont have a v8

[sircruisealotVS]

i could be wrong (as ive not done it to any of my cars before) but i think its about a grand to get 3.45 diff gears done.

[Doctor Sodways]

3.45s in a 6 are fine, it doesnt matter what engine you have, the diff ratio depending on whether you go up, ie; 3.45 (increases accleleration) or down; say, 2.7, increases top speed and reduces revs at cruising speed. Most commodores come with a 3.08 diff, some LSD, most not

Amazingly, i have a mate who managed to blow a 2.7 diff in a fairlane, god knows how, but he did it

[1991_Vn2nV]

If you want 3.45's, grab them from a VL. All VL's came with a 3.45 ratio, although the V8's had the 3.08 ratio like in the VN's and up. Ring your local diff place and get a price on having your diff changed to LSD. Im not sure what the cost is. Basically you could grab a VL V8 diff with LSD and then change the gear ratio's. The VL diff is like 20mm shorter on each side, but they fit. Doctor Sodways would have a VL Turbo diff in his car i think. I know the SV5000 and Group A's had them to fit the wider wheels, but not sure about the SV3800's.

The VL V8 diff (& VL Turbo) is a 4 pinion like the VN diff, the Straight 6 VL's only had a 2 pinion which is why you wouldnt go grabbing a VL Straight 6 diff, you'd only want the ratio's.

The perfect diff for you would be the VL Turbo diff with LSD as they were 4 pinion and had the 3.45 ratio too. But they are extremely hard to find.

[Doctor Sodways]

From what i can gather, i think i have a 3.08 LSD, but if i have a 3.45, which i will endeavor to find out about, im keepin it, maybe that will explain why my car launches so hard and bags so easily, id never thought of that

[1991_Vn2nV]

Im unfamiliar what size wheels the Sv3800 came with, but if they came with 8" wide wheels like the Group A and SV5000 it'd have the VL Turbo diff. Normal VN's only had 6 inch wide rims, and the extra 2 inches gave the guards a bit of trouble i think, hence the VL turbo diffs. Or maybe they just had a few spare vl turbo diffs lol.

[Doctor Sodways]

Well, the SV3800s came with colour coded walkinshaws, at i think 16x7, im gunna research this cos if i have a 3.45 im gunna be ecstatic

[Dezza]

sounds good thanks for all the info im going searching threw the trading post this week for a vlturbo diff

[Boonz]

, i have a mate who managed to blow a 2.7 diff in a fairlane, god knows how, but he did it

2.7's arent really that much different from the 3.08's as they only drop the revs about 700-800 rpm at cruising speed
but ur mate owns a falcon so anything is possible

[Doctor Sodways]

Owned a falcon, he bought a VR now he has a manual VY SS, but yeah, god knows how he blew the diff

[AlpineRaven]

To find out if you have or dont have LSD is to jack the rear diff up, ensure both rear wheels are off the ground. Route the wheels and if the wheel turns same direction as you are turning its LSD, if it turns opposite way, its open diff (non lsd)

If you open the cover up and count how many teeths such as 37 teeths and on the pinion has 12 teeths and on the crown, you can work it out - 37 divide by 12 equals 3.08:1 if it had 3.545 the crown shld be 39 teeths, pinion 11 teeths. - that is how you work out the final ratio on the diff.

Cheers
AP

[Doctor Sodways]

Or check the tag on the diff, most LSDs will have a tag that says "HIGH PERFORMANCE" on the diff, if it has that, its an LSD

[1991_Vn2nV]

Nah not necessarily. I read this on another forum, and apparently theres diffs with the high performance tag that are not LSD.....i'll check it out and get back to you.

[jNINE]

Keep in mind if you get an LSD centre by itself it won't include diff gears. So an LSD and gearing are two different things. You will aso need to get your speedo adjusted. I've been told the VR is based on road speed so has to be done via the chip, not sure about earlier models.

[IanG]

3.45's are a good all around ratio espeacially if you do a few road trips.
I've just put some three 3.9's in my VS. At 100K it revs about 500rpm higher than the 3.45's I had, my auto's overdrive helps heaps, if it was just a 3 speed it might be a pain on long trips. I'm driving from Brisbane to Melbourne next month so I'll soon find how much fuel it chews up. (Premium Petrol, ouch)

The diff bloke put a new set of gears from holden in plus new bearings etc etc. Cost me $920 including GST. He said he could do an lsd for $600 using recond' gears. (installed with warranty) My speedo's reading 5k's higher according to a gps gadget.

[1991_Vn2nV]

If you ring most diff places they will tell you not to bother getting your speedo changed for 3.45's. They can all tell u exactly how far it will throw your speedo out by though so its up to you.

[pandaman]

3.45s in a 6 are fine, it doesnt matter what engine you have, the diff ratio depending on whether you go up, ie; 3.45 (increases accleleration) or down; say, 2.7, increases top speed and reduces revs at cruising speed. Most commodores come with a 3.08 diff, some LSD, most not

Amazingly, i have a mate who managed to blow a 2.7 diff in a fairlane, god knows how, but he did it

Bit off topic, but I'm assuming it was a 2.77 diff in an X-series manual? If he blew one of those things behind an auto then I takes me hat off to him.

In answer to the original question, LSD borg warner centres are fairly easy to come by. If you're one of these types who's obsessed with using holden parts only, then a 3.08 ratio is gonna be the cheapest most likely. If you're willing to expand your mind a little and get your hands dirty, you could probably put 3.23 or 3.45 gears from an e-series falcon into a commodore diff. If memory serves, they both use the borg warner 78 diff yeah?

[pandaman]

If you ring most diff places they will tell you not to bother getting your speedo changed for 3.45's. They can all tell u exactly how far it will throw your speedo out by though so its up to you.

Well, with the gear ratios in the commo being set up as well as they are ya kinda have a point. Y'all have probably noticed how the top of first drops right back into the middle of the powerband in second, damn I love that. But that little bit more reduction will give it that little bit more punch ya know? Hell, if you're willing to pay for the extra fuel you're gonna burn (it's gonna happen, whether you like it or not ) then why not!

[Dezza]

yeah im not fussed bout my speedo being out the rear tires put the speedo out by roughly 8-10 km's anyway

[1991_Vn2nV]

Hey pandaman, Im actually getting my diff gears changed as well and i was going to go for 3.7's but its probably a little high for me. Is it possible to get say 3:54's to fit a commodore diff? I know they have never been put in a commodore but perhaps used in another application?

[Doctor Sodways]

Nah, he managed to blow it in an NC fairlane, with the 3 speed auto

Another mate blew a 9 inch in a falcon last week too, with the temporary 351 while the 460 gets worked, rich bastard