Brake Squeal II

[ERA Chas]

Unfortunately, I'm reviving this old thread for a reason.
I thought I had cured my ERA/Wilwood noise issue, as posted earlier, with the Wilwood shim kit, which worked perfectly-until today.
After very severe use, ( lost my mind) on an 80deg day they didn't squeal-they SHRIEKED! Three stops from 130+ to maybe 30 MPH. From the hit of the pedal, all through the stop, severe noise. I did not however, detect fade or pull. The noise was so great it caused me to ease up on the pedal in effort to STOP THE NOISE, thereby making the stops somewhat longer. (Noise didn't stop.) Only after light crusing cool-down did they cease screeching. No visible rotor grooving or scratching, in or out.
The fluid is very fresh and no other issues in the front end exist.
I'm hoping the previous participants in this thread (Bob, DonC, Chuck, Relaxin or any one else who cares has updated info or a fresh slant on the problem. I'm probably going to try the "silicone dot" method next if someone can report any success under similar abuse as described.
I just can't accept that Wilwoods will "be this way", when Brembo's, AP's or Baer's
on exotics (Porsche's, Lambo's, Ferrari's) far heavier than our cars suffer no such problem and have surperb braking power.
Do you track rats have a secret to share?
Sorry for the whine and rant. I'm making more noise than my brakes!
Appreciate any help/interest in this subject.

[ERA Chas]

[Mike Simard]

What pads do you have? Did you bed them?

[ERA Chas]

Mike,
Yes, they've been properly bedded and have been on the car two years. (maybe 4000 mi).
They are Sierra "soft" pads as supplied by ERA.
All the conventional fixes have been discussed and tried by other members in a previous thread, (titled "Brake Squeal", here on Putnam Forum) which is what makes this so difficult to correct.
Thanks for responding and any thoughts you have.

[strictlypersonl]

I'm trying out (with another customer) some new pads and some other secret stuff. We should have results of the experiment in a couple of weeks.

[ERA Chas]

That's welcomed news but am worried about the"$$ecret $$tuff" .
Promise not to stop the car for the next couple 0'weeks
Thanks and looking forward,

[Mike Simard]

Chas, I've been eliminating brake squeal too and have tried different Wilwood pads. Wilwood has about 10 pad grades. Most are high temp race pads but there are 3 lower temp grades that could work on the street. I started with the "T" grade that came with a Dynalite kit. They are cold stoppers that are very quite, stop well cold and fade badly on the track. Next up I tried the "E" grade which have a fairly high temp range for a 'streetable' pad. They squealed horribly loud and were probably eating the rotors. I tried machining the metal backing flat and lubricating the pad-piston contact area but nothing got all the squeak out. Now I have the "Q" grade, they are in between the T and Q for temp and are dead quite on my car, they are machined flat and have lubricant but no shims. I'm finally happy but do plan to swap pads for the track. I wonder what Wilwood grade your Sierra pads are equivalant to? BTW, I did try shims briefly but felt that the pedal was a bit softer. Lubricating the pad-piston contact seems to be very effective, I used some gooey engine assembly lube because it was handy. BTW2, you were making stops from 130? You can heat a pad up hot enough to warp the metal backing, I've done it. If that surface isn't flat to the piston they could be like vocal chords.
edit: changed first reference of "E", did say Q, Doh!

[chuckbrandt]

ERAChas,
What does the contact surface look like on the pistons where they contact the pads? Mine are pretty thin on the Sierra calipers like less than 1/16" and not full circle. I'm sure this is for cooling but it would seem to me after a while they might cut right through those shims. I'd be interested to hear if you pulled your pads now what the shims look like.

Good luck,

Chuck

[ERA Chas]

Mike S,
Very much appreciate hearing your experiences. Interesting question Wilwoods equivalent pad to Sierra. I suspect there might not be one with exact properties because Bob supplied Sierra pads when I bought the brake kit from ERA, not Wilwoods. I believe they're on Chuck's car, DonC's and pal ERA-FIA's as well. BTW, I'm using Permatex dark green brake pad lube and it holds up to heat well. Appreciate your track testing results.
These Sierras have stopped beautifully, both street (when warmed somewhat) and track, without fade. The shim kit stopped the noise until the day I posted, which makes no sense. Unless your excellent point about warping the backings happened. Vocal chords is a good analogy. However, the brakes performed normally and powerfully shortly after and in stop/go traffic. Hard pedal and no pulsing.
Chuck,
Agree about the piston wall thickness but I got full circle contact on pad backs (before shims) but haven't seen the shims just yet.

My plan now is to tear-down when Bob has a result or product to work with. Then I'll see if the pad backs warped as Mike said or if I'm making sushi out of the shims.
Bob's a great engineer and I have faith he'll find a good solution for all of us.


Very glad to hear from you guys.

[ERA-FIA]

Strictlypersonal, secret stuff ...we will be watching you

[strictlypersonl]

It's secret because it has only a small likelihood of working...

And I'm trying to encourage an air of mystery.

[ERA Chas]

After that GLOWING compliment I paid you...
If it doesn't work, your kaiak is in danger of developing .45cal leaks...

[ERA Chas]

Do we have any top-secret test results from Area 51 yet???
Noisy brakers want to know

[ERA Chas]

Calling Groom Lake, calling Groom Lake - come in please...

[relaxinrob]

Chas,
Is it your front brakes or back brakes? or can't you tell? The reason I ask is that I have Wilwood 4-piston brakes on the back of my coupe and they were making a shreek and I found it was the emergency brake pad assembly that was doing it.

Rob

[ERA Chas]

Absolutely the fronts. I also took great care with the e-brake adjustment so as not to rub. Can start fires that way.
Pending what Bob develops, I'm prepared to use your "silicone dot trick". That's if Bob has not had satisfactory test results with his parts.
Thanks for the thought.

[DaveR]

Mike S,

You might want to edit your post, I think you meant to say that you tried the E pad then went back to the Q pad. Are you planning to try the Q at the track, or switch back to the E at the track. I just bought a set of E pads for the front, and will buy another set for the rear, unless you think the Q pad would be sufficient for the track.

[Carroll DeWeese]

I run the E pads on the track. They work very well on the track but they are very dirty. T are good for the street. T are specifically low noise. Try changing your pads and see if you still get the noise. If you do after the pads are bedded, then you might have a rotor or calipar problem.

[Mike Simard]

Originally posted by DaveR
Mike S,
You might want to edit your post, I think you meant to say that you tried the E pad then went back to the Q pad.

Thanks for pointing that out, I goofed.
Yes, after having the "T"'s that came with the kit fade at the track I tried the "E"'s. They squealed badly on the street and as Carroll says, they make alot of dust. the dust wouldn't be a problem but the noise was unbearable. The "Q"'s seem to be a practical street pad. I plan on putting the noisy "E"'s in for the track but that's just because I have them, there are several Wilwwod race grades too. I hoped the E's would be a dual use pad. There really is no dual use pad anywhere, the best way is to change pads for the track, of course it's even better to have matched rotors for each pad set and change those as well. It's a viscous cycle!
BTW, here's some brake links:
Wilwood grades: http://www.wilwood.com/BrakePads/003-DESC/index.asp
Good brake tech!:http://www.stoptech.com/technical/

[ERA Chas]

Unless you promptly divulge the super-secret results of your brake testing, there will be a break-in at the office of your psychiatrist [and you must have one, I've seen your co-workers] and the vital information will be made public.
You have been warned.
Deep [Carburetor] Throat