My new (to me) AOR showed up today :)

[crackership]

YAY!

It's even got an AOT ring and pinion in it

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[stitch2k1]

What's with the AOT ring and pinion?

[crackership]

What's with the AOT ring and pinion?

The AOT (S2) ring and pinion is a shorter final drive of 3.875 vs the AOR (Turbo) final drive of 3.375. Basically trading some of the top end for acceleration. The S2 does have a taller 5th gear, so I'll be revving slightly higher on the highway but I think it'll be worth it.

Turbo transaxle with standard final drive

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Turbo transaxle with S2 ring and pinion

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S2 Transaxle with standard final drive

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[Latitude48]

What's with the AOT ring and pinion?

The AOT (S2) ring and pinion is a shorter final drive of 3.875 vs the AOR (Turbo) final drive of 3.375. Basically trading some of the top end for acceleration. The S2 does have a taller 5th gear, so I'll be revving slightly higher on the highway but I think it'll be worth it.

I'm going a different route that should yield comparable results. I'm getting a 968 6MT (G50 Differential), which has the following ratios compared to the standard AOR and AOR with AOT Final:

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The trans I'm getting has the M220 option with Torsen differential, but I'll probably have the Torsen pulled and replaced with a Wavetrac torque-biasing diff (have two of them in my A4, which I like a lot), or bite the bullet on the Guard GT2 Pro G50 ($$$).

[Thom]

I would not choose a TBD for our cars as I think the differential needs to limit the speed differential between the rear wheels when braking hard. Losing the rear end when braking hard, especially with the stock front-biased brake balance is a no-no. I love my OS Giken LSD which has saved me a few times under heavy braking.

[Latitude48]

I would not choose a TBD for our cars as I think the differential needs to limit the speed differential between the rear wheels when braking hard. Losing the rear end when braking hard, especially with the stock front-biased brake balance is a no-no. I love my OS Giken LSD which has saved me a few times under heavy braking.

The Wavetrac provides some lock-up under braking, but I don't know if it's as effective as a clutch type LSD. I used to have a Guard Torque-Biasing diff in my S2 but changed to the Guard clutch type LSD back in 2004. Too bad the prices have gone up by a factor of 2.5 since then.

FWIW, I didn't have front and rear Wavetracs installed in my A4 because I had a ton of HP; I don't. I wanted them for the wet weather performance and ability to get up our hills if we get snow, and for that they work superbly.

Cheers!

[Thom]

Back when I was shopping for an LSD it wasn't really clear to me how well or bad the Wavetrack would work under heavy braking, and even if I had it high on the list as it was not too expensive I ended up erring on the safe side and went for the clutch-type OS Giken instead.
The first time I realised how good the OSG was was driving in the rain. I deliberately floored the throttle on a very wet (and deserted) road and felt a remarkably progressive lock-up of the rear wheels and the car stayed absolutely straight. Genious. Far more progressive than the 40% original LSD found in the usual 951 trans and safer than any TBD in my opinion.

[Latitude48]

Back when I was shopping for an LSD it wasn't really clear to me how well or bad the Wavetrack would work under heavy braking, and even if I had it high on the list as it was not too expensive I ended up erring on the safe side and went for the clutch-type OS Giken instead.

I'm definitely leaning towards the OSG now. The Guard GT2 Pro is now $3500+ if you can find one, and for me I doubt it offers any advantage over the OSG, which I think I can get for about $1785 from an online site that gave me a 10% off coupon for signing up for their newsletter.

With the Guard LSD in my S2 I can spin both rear tires in the wet if I floor it in 1st gear. If the OSG is more progressive in its lockup that may work better in our wet weather.

BTW, I downloaded a gear ratio spreadsheet from GBox and if I plug in your 17" tire specs, I get the exact same results you posted.

[Thom]

You should love the OSG. I have not driven a car with the Guards LSD which is said to be the best especially for track use, but honestly the OSG really is that good IMO especially in the wet.

[Latitude48]

Unfortunately, the OS Giken G50 is not available until the next production run expected about the end of February. I've already had the trans shipped to Catellus Engineering, and I think Kevin would be OK with waiting on the part, but I don't want it to be an issue, so may reconsider the Wavetrac. Kevin's data point on the Wavetrac is an SCCA racer that keeps winning at nationals, and he loves the Wavetrac... and he also has a PHD in Mechanical Engineering (I'm a couple of degrees short only having a BSME, ha, ha).