Steve makes some valid points about the brakes squealing, from
vibrations at the caliper/piston and the back of the pads. This explains
why many cars use the anti-squeal shims. However, squealing can still
occur in spite of these shims and other measures. Since I found relief
from this by changing the pads themselves (to semi-metallic) I needed to
know more. So I contacted the Repco "tech man". (His answer is
attached below)
I have also found that the semi-metallic pads resist fading far longer
than the organic pads, in repeated usage, such as in autocrossing. It is
said that these pads will wear out the rotors faster than the organic
pads. Sounds reasonable, but my rotors are only .006 thinner in the pad
area than outside of it. (.494 vs. .500)
Now here's Robert's take on this:
E-mail message
From: robert@man-a-fre.com (Robert) Date: Wed, Nov 5, 2003, 12:30pm
(PST+1) To: tr6taylor@webtv.net Subject: re: Semi-vs. organic
To Dick
Most brake squealing is due to the rotor surface heat glazing is one
major factor for brake squealing. When the rotors are turned there are
different speeds and cuts on the brake lathe. The final cut should be
smooth,slow,steady and small cuts.Thank You Robert Robert
Man-A-Fre Sales
If I can assume something from this, it would be that the metal in these
pads have an on-going cleaning or de-glazing action going on thru brake
use. I have found no down-side from using them.
Dick
'73
|