Ordered the R4-1 (Wilwood Superlite 7420 front / Stock RX-8 rear -- Installed on brand new front and rear rotors) based on the recommendation on the website that it is a good "dual use" pad.....that has NOT been my experience at all! First of all I was actually sent the wrong pad shape, so I was hopping perhaps they had sent the wrong compound as well...at least that might explain my experience.
While the R4-1 does provide good initial bite from cold, and fading (at auto X) is a non-issue. It is horrendously loud, it doesn't squeal, it SHRIEKS! -- cold, warm, hot, on track, on the street, in the garage. It's so loud corner workers were complaining. I called Porterfield directly and they were less than helpful.... "...A race pad will make some noise....we don't quantify squeal....ect "
Increased dust is just a fact of life, and I'm willing to accept "some noise" for increased performance, but these things are ridiculous. Literally EVERY time you think about touching the brakes, from any speed the entire county knows. You would have to be deaf to consider these acceptable for more than an interstate cruise to /from the track.