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Hi guys

I'm looking to upgrade to an LSD later in the year and just wanted to confirm a few details. I have a 97 NA8 so the diff ratio should be 4.1 open diff. Is there an easy way I can confirm that I have open diff, I have no history of the previous owners? I bought the car at a car yard and it had mainly cosmetic mods to it, so I'm thinking its unlikely to have a LSD as the rest of the car is mechanically stock?

Option 1
Torsen insert - this would keep the 4.1 ratio but I will have LSD and no speedo issues. Lower purchase price, more labour costs.

Option 2
Complete torsen diff assembly - this would change the ratio to 3.9, resulting in slightly slower acceleration and throw out the speedo. More initial purchase price less labour costs. (could probably be done at home with a jack, stands and a mate)

Option 3
6 speed + Torsen insert - Higher gear ratios + 4.1 diff, better acceleration but speedo out?

Option 4
6speed + Cmplete Torsen Diff - 3.9 diff ratio and no speedo issues?

Option 5
??????

I will mainly be doing motorkhana and lap sprints around Hidden Valley raceway. With a 1.1km straight, I'm thinking top speed will be more important than acceleration. Keeping the 5 speed and just replacing the diff is most realistic budget wise at the moment, but I would like to know the impact if I decide to get a 6 speed in the future.

thanks for any advice.

CQYD wrote:Option 2
Complete torsen diff assembly - this would change the ratio to 3.9, resulting in slightly slower acceleration and throw out the speedo. More initial purchase price less labour costs.

TorSen I in Aust is OEM in 93-95 Clubman & is 4.1.

TorSen II was typically 3.9 in ADM NBs when fitted, but also 3.6 in ADM 10AE.

Option #:
Purchase 4.3 torsen from jdm version, fit (not that expensive if you pull the diff the drop it too a shop.

Live with Speedo issue or fit Speedo correcting cable our otherwise.

Option ##
get cheapist torsen possible, buy kia 4.7 gear, live with Speedo or correct.

Standard mx runs out of power long before revs, so the quick diff is unlikely to hurt your times.

Sent from my GT-I9100 using Tapatalk 2

CQYD wrote:Hi guys

I'm looking to upgrade to an LSD later in the year and just wanted to confirm a few details. I have a 97 NA8 so the diff ratio should be 4.1 open diff. Is there an easy way I can confirm that I have open diff, I have no history of the previous owners? I bought the car at a car yard and it had mainly cosmetic mods to it, so I'm thinking its unlikely to have a LSD as the rest of the car is mechanically stock?

Option 1
Torsen insert - this would keep the 4.1 ratio but I will have LSD and no speedo issues. Lower purchase price, more labour costs.

Option 2
Complete torsen diff assembly - this would change the ratio to 3.9, resulting in slightly slower acceleration and throw out the speedo. More initial purchase price less labour costs. (could probably be done at home with a jack, stands and a mate)

Option 3
6 speed + Torsen insert - Higher gear ratios + 4.1 diff, better acceleration but speedo out?

Option 4
6speed + Cmplete Torsen Diff - 3.9 diff ratio and no speedo issues?

Option 5
??????

I will mainly be doing motorkhana and lap sprints around Hidden Valley raceway. With a 1.1km straight, I'm thinking top speed will be more important than acceleration. Keeping the 5 speed and just replacing the diff is most realistic budget wise at the moment, but I would like to know the impact if I decide to get a 6 speed in the future.

thanks for any advice.

Hi Sailaholic,

I've looked at this fairly extensively:

My advice, 4.1 with Torsen - they are available for about $900 from most importers. One that sponsors this site does them regularly
Combine that with a 6 speed box and get the right coloured gear from a 5 speed that has a 4.1 rear end. Some of the race guys may swap yours for theirs...
Race cars really only need to monitor pit lane speed
This will provide great acceleration, heaps of fun, the speedo should read right (providing you haven't got 17 inch wheels ) and will be a great car on the track. This is the set-up I had in my NA 1.8 race car the only difference was that I had a kaaz 1.5 centre which is noisy for a street car.

colster3 wrote:

CQYD wrote:Hi guys

I'm looking to upgrade to an LSD later in the year and just wanted to confirm a few details. I have a 97 NA8 so the diff ratio should be 4.1 open diff. Is there an easy way I can confirm that I have open diff, I have no history of the previous owners? I bought the car at a car yard and it had mainly cosmetic mods to it, so I'm thinking its unlikely to have a LSD as the rest of the car is mechanically stock?

Option 1
Torsen insert - this would keep the 4.1 ratio but I will have LSD and no speedo issues. Lower purchase price, more labour costs.

Option 2
Complete torsen diff assembly - this would change the ratio to 3.9, resulting in slightly slower acceleration and throw out the speedo. More initial purchase price less labour costs. (could probably be done at home with a jack, stands and a mate)

Option 3
6 speed + Torsen insert - Higher gear ratios + 4.1 diff, better acceleration but speedo out?

Option 4
6speed + Cmplete Torsen Diff - 3.9 diff ratio and no speedo issues?

Option 5
??????

I will mainly be doing motorkhana and lap sprints around Hidden Valley raceway. With a 1.1km straight, I'm thinking top speed will be more important than acceleration. Keeping the 5 speed and just replacing the diff is most realistic budget wise at the moment, but I would like to know the impact if I decide to get a 6 speed in the future.

thanks for any advice.

Hi Sailaholic,

I've looked at this fairly extensively:

My advice, 4.1 with Torsen - they are available for about $900 from most importers. One that sponsors this site does them regularly
Combine that with a 6 speed box and get the right coloured gear from a 5 speed that has a 4.1 rear end. Some of the race guys may swap yours for theirs...
Race cars really only need to monitor pit lane speed
This will provide great acceleration, heaps of fun, the speedo should read right (providing you haven't got 17 inch wheels ) and will be a great car on the track. This is the set-up I had in my NA 1.8 race car the only difference was that I had a kaaz 1.5 centre which is noisy for a street car.

would that also be a good option for a dd ?
and thats its going into a na6 ?

If its just a DD, then you don't really need a LSD, its just a lot of cost for something you won't need or use 95% of the time. Plus in a NA6 you will need a 1.8 diff housing and half shafts which adds to the cost and complications.

I'll most likely be getting Torsen insert and keeping the 4.1 ratio. But plans for the LSD have been pushed back until I get my clutch sorted.

From what I've read its an upgrade that can be felt right away. I don't mind the extra costs because it doesn't seem to be too much (not sure about labour wise). I too am installing a new clutch atm

mito wrote:From what I've read its an upgrade that can be felt right away.

Correct.
I have a Torsen T2, with the stock ratio etc. (I swapped from an open diff)

The difference was noticed at the first corner, you can feel the back of the car holding a lot more grip.


Personally, I'd suggest having a drive of a car with one in it, then decide.

For me it was one of those things where I didn't need an LSD, but now I have one it's great. (most of my fun is re-learning the car)

hks_kansei wrote:

mito wrote:From what I've read its an upgrade that can be felt right away.

Correct.
I have a Torsen T2, with the stock ratio etc. (I swapped from an open diff)

The difference was noticed at the first corner, you can feel the back of the car holding a lot more grip.


Personally, I'd suggest having a drive of a car with one in it, then decide.

For me it was one of those things where I didn't need an LSD, but now I have one it's great. (most of my fun is re-learning the car)

That whole quote there just makes me want one

CQYD wrote:Hi guys

I'm looking to upgrade to an LSD later in the year and just wanted to confirm a few details. I have a 97 NA8 so the diff ratio should be 4.1 open diff. Is there an easy way I can confirm that I have open diff, I have no history of the previous owners? I bought the car at a car yard and it had mainly cosmetic mods to it, so I'm thinking its unlikely to have a LSD as the rest of the car is mechanically stock?

Yes,
Put one wheel in the grass/dirt one wheel on the tarmac then drop the clutch, if it drives away LSD.

Not with a torsen, that just doesnt necessrily work.

Dann