Do i need a torque biasing diff. for autocross....... Options

[Dominic L]

I'm moving up to modified class (Sm2) with my "new to me" -6. I would like opinions from people who have used these for AX. I would think that i could limit the inner tire from spinning somewhat with the rear suspension settings (read "cheap out"!!) but if the TB diffs are really worth it, now would be the time for me to go for it since i have the transaxle out. Also recommendations of someone who can do the diff swap in the Northeast would be helpful.

Thanks

[okieflyr]

I have a season of auto-x on my Quaiffe now. My car is trailered to the events, and not used on the street, as I'm in XP (IMG:style_emoticons/default/sawzall-smiley.gif) . I'm churning enough tq=230 down low,and 206 hp to use it. I would hate NOT having it. I'm still dialing in my suspension needs, and am trying to keep the rear tires down for better bite.
I'm getting alot of power-on oversteer, and it is a blast to drive, but things for me need more work. I suspect the lockup characteristic and my then too soft suspension, combined with too much weight transfer on corner entrance is hurting things. I do not feel the diff when driving. Steve Limbert@Aircooled Racing, did my install. He is located outside of York PA. He knows his way around the 901 well, but he takes on alot of work, and staying in close communication will help keep things moving along. With the new season coming up, his race schedule will build.

If I remember correctly, this car is fairly new to you. How much are you looking to auto-x it? It has some beautiful black paint that will suffer w/rock chips.
You MAY want spend a season getting aquainted with your new ride, and then plan your upgrade priorities....

Kevin

I'm moving up to modified class (Sm2) with my "new to me" -6. I would like opinions from people who have used these for AX. I would think that i could limit the inner tire from spinning somewhat with the rear suspension settings (read "cheap out"!!) but if the TB diffs are really worth it, now would be the time for me to go for it since i have the transaxle out. Also recommendations of someone who can do the diff swap in the Northeast would be helpful.

Thanks

[914forme]

TBs are the bees knees if you can keep the rear tires on the ground, if not it is no better than an open diff. Once the tire is off the ground it has no way of knowing where to put the torque - unfortunately it chooses wrong and applies it to the lifted wheel. I fought the same thing last year I went with a ZF for 2 reasons.

One I take no points for putting it in, with the 40% lockup I choose, the TB would have been 3 points. And two if my new suspension setup still allowed the rear to get off the ground, I could keep the power down. The ZF being a clutch style, means that the tires will continue to receive power. And I continue to go forward.

[Dominic L]

Kevin, the paint job is nice but the digital pics make it look much nicer then it really is. It has it's share of bumps and nicks. Not too concerned about the paint. I plan on autocrossing it as much as i can with MSNE, NNJR PCA, and probably some SCCA events at Englishtown.


Stephen, I may go the route you went with the 40% lockup diff when the time comes since it seems less dependent on the suspension settings to work properly.

Thanks to both of you for your input!

[ArtechnikA]

Gary Fairbanks is another well-respected trans/diff guy in the NE. CT.

[i love porsche]

dominic..when did you get a 6! i cant wait to see it