Right after buying my 74 GTV I went to a drivers school at "Streets of
Willow," a very short track with lots of turns...very hard on brakes
and tires, and really rather unpleasant after 3 or so drivers schools.
But the first one was a big thrill.
Anyway, regarding brakes...after my first session when I came off the
track there was smoke pouring out of both front wheels. No
discernible fade but the smoke scared me. So I bought cross-drilled
rotors from Alfa Ricambi before the next event. Voila, no more smoke
and brakes have been excellent ever since. It's true, the cross
drilling eats up pads a lot faster and I have to get the rotors turned
about once a year of time trialing. I also put on braided steel brake
lines. Pedal is high and hard.
I put cross drilled rotors on all 4 wheels. But on the non-transaxle
cars, it's probably only necessary on the fronts. Most of the other
time trialers do the same.
As for the transaxle cars, I have a little experience there as well.
On the GTV6 the fronts are vented and probably don't need drilling or
slotting. The rears tend to overheat and might benefit from drilled
rotors.
It is not recommended to drill them yourself. You would need a very
hard drill. And know the right pattern for the holes.
Slotted rotors would probably be less destructive to pads.
Doug Bender
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