I say "pshaw," my good man...
The spec line data is a hold-over from the process that translated old SS cars into the IT rules - back when the ITCS was a separate publication. The only time that information bears on practice is if a specific exception is noted (BMW fuel cell location, allowance for Petty bar cages, or the MR2 aero kit that was technically an option but that damn near EVERY car came with).
Up to the point where an exception is defined, the rules - the letter thereof, ignoring common sense - 'spect you to use OE parts under "D. AUTHORIZED MODIFICATIONS," wherein IIDSYCYC is defined in way more words.
There is no provision to use anything but OE manufacturer brake rotors, ipso facto we aren't s'posed to.
Now, for YEARS we have collectively used "OE-equivalent" parts where they are not specifically allowed - as they are for hardware, belts, and gaskets - and not worried about it. I actually sourced OE rotors for the Golf because (a) I don't like setting myself up to be called a hypocrite, and (
it is EASY for me to take the moral high ground because they are neither outrageously expensive nor impossible to find for my car. I ordered the Brembos to use in non-SSC races (NASA, hillclimbs, whatever) because (a) they were cheaper (no tax, free shipping), and (
I like to try differnent options to learn things.
The bigger point here is that we should collectively decide which way we want it: If the rule is "good" as written, it should be enforced. If it is "dumb," it should be changed. The precedent that we set by accepting loose interpretations for this rule are easy for folks to translate into others. I believe in the concepts of "gateway drugs" and "broken windows," by the way...
For example, there's no tolerance spec for the keyways in Miata cam pulleys listed anywhere, so it MUST be OK to mill them out and take advantage of the slop to change the intake/exhaust overlap. Do you think that "pro-built" engines make more power because they re-balance parts in an already well-balanced engine?
Pshaw.
K
EDIT - the point at which Mazda tells you that they have non-Mazda rotors for sale, we fall back on the points in my previous note.
[This message has been edited by Knestis (edited December 21, 2003).]