kineda

I'd like to get the factory S4 rotors and then have a machinist slot them. Anyone know a good play in the bay area to get this done?

Gorobei

I'm no metallurgist, but I have to imagine that subjecting the rotors to that kind of stress/process post-production would seriously compromise the integrity of the rotor. I can't imagine it would be *that* much more expensive to buy a set of pre-slotted rotors that have the slots designed into them. Besides, the S4 rotors aren't known to be an exceptionally quality piece. They are heavy, one piece, not vented, and excessively prone to warping under heavy track conditions. I don't know how many S4 people I've seen post or spoken to personally who have told me about warping their rotors after just one day at the track. I was at 2nd Creek in Denver a few weeks ago, and the 2 S4 drivers who seriously ran the track that day (Wagonboy and Uzanak) were both complaining of possible warping after 30 laps or so. You may never track your car, but I still wouldn't recommend slotting those suckers, regardless. The rotors alone are an okay upgrade if you won't be tracking, but I really don't think having them slotted is a very good thing to do. Maybe I'm an idiot, though.

Another $0.02,

B

pointby

I had my rotors slotted by a machine shop and I have since run them at two auto crosses and a couple track days plus 10,000 miles on the street.
no problems.

Reggie

You are better off buying new rotors or pads if performance is an issue.

Contact Gary@Ronal - he might know of some. I bought my slotted cross drilled DBA rotor from him for my A4 (a looks thing only - not performance)

Reggie

98.52.8QMS