11 replies to this topic

[LDadrenaline]

I have a 95 and have a chance to get my hands on a 95 diff for a good price. Is there any way to swap out the ring and pinion inside to the 99 spec we can use? Or is it not even worthwhile?

Thanks,

L.D.

[davew]

I don't understand.........
You have a 95 (assuming with a 4.10) and you can buy a 95 (assuming another 4.10) but you want to convert to a 4.3. Why by the wrong ratio (4.1) to convert to the correct ratio (4.3)?? Wht not just by the 4.3 and be done?? Or am I missing something????

[LDadrenaline]

I can get the 4.1 for about $175... Since that's cheap, is it cost-efficient to buy it and convert it to 4.3? Or just cheaper/easier to buy the 4.3?

[Greg Kimble]

LD,

I bought a low mileage open diff from a 20XX Miata, took it to my favorite SM shop and had them put my torsen into the 4.30 while we waited, the total cost was about $300, including having the new diff shipped to us.

Greg

[Motor City Hamilton]

How expensive is the 4.3 gear?

I bought a 4.3 from Panic Motorsports. Easier to unbolt LSD from the pumpkin and bolt up the new than it is to disassemble and realign the pinion gear. Have a nice Torson 4.1 boxed up in my garage that needs to go on ebay.

[Ron Alan]

I can get the 4.1 for about $175... Since that's cheap, is it cost-efficient to buy it and convert it to 4.3? Or just cheaper/easier to buy the 4.3?

You don't say but I assume your original diff is a torsen. Find a open 4.3(99+)and have your torsen installed in it...as the above post suggests...but make sure this is done by someone with the correct tool to check lash. If you have the extra cash buy the 4.1 open and put it on the shelf. You'll be someones best friend when they get taped a little to hard in the rear and their housing/carrier breaks!

If you find a 4.3 Torsen then you can just swap and sell your torsen to recoup. But many will tell you to use the Torsen 1 out of your original rather than the Torsen 2 in the newer.

[Motor City Hamilton]

But many will tell you to use the Torsen 1 out of your original rather than the Torsen 2 in the newer.

Can you expand on this comment? I know that there is a visual difference in the older Torsen and the newer and 0.1 lbs difference in weight. Does anyone know the mechanical differences?

[Motor City Hamilton]

Googled it trying to answer my own question and just got more confused. Does anyone understand these graphs?

http://www.torsen.com/products/T-1.htm

http://www.torsen.com/products/T-2.htm

The TORSEN T-1 Traction Differential is available in any torque biasing range from 2.5:1 to 5.0:1

TORSEN T-2 Traction Differentials are available with a biasing capability range of 1.4:1 to 3.0:1

[Ron Alan]

Again no expert here, just what I've read on other sites. I Googled "difference between T1 and T2" and found an old discussion. Plus I was told by a couple different racers in our region(top guys) this combo was better...for what that's worth.

What I got that made sense was that when the T1 locks it allows the wheels to rotate at a different speeds. The T2 doesn't which tends to cause more of a push when on the throttle early. T1 allows more of an early throttle? I hope someone corrects me if this is incorrect...don't have time at the moment to look up the article I read and post the link.

[Jim Drago]

The 4:1 diff has no real value at all.

If you have an open 4:3, you can easily bolt in the torsen unit from a 4:10 and not have to change crush collars and bearings etc.

But if you have a 4:10 torsen and try to put 4:30 ring and pinion in, it is a job and you will have 4150 in parts to buy as well.
Jim


Best option if you have 4:10 torsen is buy a 4:30 open and swap the torsen,

If not buy a used 4:30 torsen

You can find deals on them from time to time. However ours come with 6 month warranty. You just have to weigh it out and make whatever decision is best for you


Jim

[Motor City Hamilton]

This site is better; the actual Torsen site. http://www.torsen.co...ts/products.htm

Trying to decode this:

The TORSEN T-1 Traction Differential is available in any torque biasing range from 2.5:1 to 5.0:1

TORSEN T-2 Traction Differentials are available with a biasing capability range of 1.4:1 to 3.0:1

I read this as the T2 will allow differing rear wheel speeds at a lower torque than the T1, but will also reach a locked condition at a lower torque. I don't see how the T2 would be causing more push at apex? I'm not one that belives the "well a fast guy said it." I'd like to know why.

[Ron Alan]

This was the link I originally read...starts out with guys praising the T1 then someone saying how it's weaker than than the T2. If someone has a real track analysis of the 2 types side by side post it up!

http://forum.miata.n...ad.php?t=352041