Wilwood Polymatrix Pad Comparison: A vs. H
 

Hey Guys, I'm trying to finalize pad selection for my W6A (race) front brakes. Looking at the H but also noticed the A. Based on the chart is looks like H has the best linear rise in Cf over the temperature range. A has a pretty steep rise with at low temps with minimal drop off at the high temps.

How many of you guys have used the H pads on the street? The Wilwood rep told me they would destroy the rotors on the street at low temps.

Attachment 41040

Don't they have an "E" pad as well? Unless I'm wrong, that is what Wilwood had me switch over to a few months ago. The B.P. 20 will drop off pretty quickly under hard use on a road course with heavy and frequent braking zones if you're in a heavy car. Auto cross is not so much of a worry unless you're running constantly for some reason. I would not put a really aggressive pad that needs a little bit of heat on a car that sees a lot of street miles. The "E" pads need a little bit of heat and do wear rotors but they aren't noticeably bad on the street.

Hey Matt, yes they do have an E compound, but that is considered the high end of the street performance category.

Street Performance Pads:
Attachment 41055

Track Pads:
Attachment 41056

After reviewing these charts side by side I can understand why you wouldn't like the BP-20s on the track. They show a really shallow slope with the peak Cf (~.52) at nearly 900 degrees F! The E is slightly better, but still needs to be at 500 degrees F for max Cf (~.475).

I'm surprised that the track pads (A & H) have an initial Cf (~.55) rising above Cf (0.6) at 500 degrees. What is interesting is the initial cold torque is far superior to the street performance pads. I guess the major consideration is rotor wear :_paranoid

yep, rotors are a wear item. :D

Josh,

I have a lot of experience with all of these pads, but i'm not clear on your application. I probably missed this, but please clarify your planned usage for the car.

Is it all track? 90% street / 10% track?
Are you AutoXing ... or running 1/2 hour sessions on large road courses?

Thanks.

.

Yep, they are consumables, very high priced consumables ;-)

Ron, thanks for your questions. I'm building my Chevelle to primarily run ASCS, GG Auto-x, and the occasional track day at some of the great tracks in Nor-Cal. It is difficult to estimate percentages, but I would assume 60% track / 40% street. I realize there is not a single pad compound that works in all situations and would tend to bias my selection towards performance on the track rather than street.