[Guest]

Well, if you clicked on this t

Well, if you clicked on this thread with that thrilling title, you are a true F-talk tech guy...

Anyway, was reading about ABS and the author made the statement that ABS required a negative scrub radius to work well. I know this is borne out in Ferrari Practice when they went to the large offset wheels on the ABS 328s to enable a negative/zero scrub radius.

While he did not go into why ABS needs a negative scrub, I'm guessing that with much of a positive scrub a differential application of the ABS left to right would tend to yank the steering wheel away and increase instability, while a zero or negative scrub would be more tolerant of L/R differential braking caused by ABS.

Does this sound right?

In addition, I would also guess that the Mondial came with almost zero scrub even without ABS to help with the steering effort, while the 308 series carried about 7/8 - 1" of positive scrub radius for road feel and bite (by my rough calculation - please correct me if I missed). Would make sense as I have often heard that 308s have some noticable bump steer.

Any clarification to help understanding ABS geometry better would be great
Many thanks
Russ

 

[Guest]

Hey Russ,
Your makin

Hey Russ,
Your making my head hurt on this one. This is a hold new deal. ABS impact on Geometry.

Might lose some sleep thinking about this one.

 

[Guest]

Bob - [IMG]http://www.ferrari-

Bob -

Heard back from some folks that the ABS pulling unevenly side to side was why there is a minimum of scrub radius. Could even jerk the wheel out of your hand!

My head's always hurting!

best
rt

 

[Guest]

Interesting article about scru

Interesting article about scrub...

http://www.hrsprings.com/site/technical/scrubradius.html

Thanks guys...I learned something new today!

David