Brake dust shields?

[indiana dave]

Believe it or not, I just took the front brakes off my car for the first time since I got it. (actually, I think I put new pads on it right after I got it... 7 years ago.) Mainly to see how the dust shields were attached and remove them. I noticed that the inner wheel bearing seats against the dust shields. Did you guys keep the center part of the shield and trim it off? or remove it completely?
Also, can you get that cloth seal, or whatever it is behind the dust shield? I've never seen anything like it before.

I can't believe how good my brakes look, after 25,000 miles, dozens of autocrosses, and a couple of open track events.
They overheated at the opentrack events, even with the ducts, but the pads have so much material, they almost look new. The rotors are also in great shape... I'm tempted to just throw it back together, and hope they'll stay cooler and not fade as bad without the shields...
Naw, I'll probably upgrade the pads at least, and put on some braided lines.
I also run synthetic brake fluid.

I'd like to upgrade to the 12.19 wilwoods, but don't need the hassle... maybe next winter. Besides, I can't find anyone who can get them.

[CP86SVO]

Before I converted to SN95/Cobra brakes, I removed the entire dust shield, since I don't drive my SVO in the wet, and it isn't my daily driver. I found that removing the shields help quite a bit for brake cooling for open track driving.

If your SVO is a daily driver, I would leave the center part of the shield on and trim away as much as you can of the dust shield, since the center section protects the inner rotor bearing seal. Don't worry about the foam gasket that goes underneath the shield, since the dust shield usually sits pretty flush with the spindle already, and very little to no crud can reach the inner bearing seal.

If you overheat the brake fluid, you must change it and bleed the system right away; boiled brake fluid isn't good...what kind of "synthetic" brake fluid did you use?

I also had Earl's stainless brake lines, Hawk HP pads, Maximum Motorsport brake caliper bushings, steel caliper pistons and Motul 600 brake fluid (dry boiling point about 600 degrees F). I found this combination OK for street driving and open track driving with a stock motor; add more power and speed, you'll need more brakes.

Where did you point the brake cooling ducts at?

HTH WS

[indiana dave]

I don't drive my car every day, but I drive it to cruise ins, and to shows and to the track. I get caught in the rain, so maybe I need to keep the center part of the shield and trim the rest off.
I used Valvoline synthetic, and it says it's boiiling point is "over 500deg."
I ziptied some metal dryer duct to the tie rod ends and aimed it towards the rotor.
Last year, I didn't have the ducts, and my brakes were literally smoking when I came into the pits.
This year, with the ducts, they didn't smoke, but they did start getting soft later in the runs.
I'm still amazed how good the pads and rotors look though, as hard as they've been used.

I've been considering these rotors,
http://cgi.ebay.com/ebaymotors/ws/eB...tem=2444471441[/URL]
and have seen so many mixed reviews on pads, I'm undecided. I definately am hoing with the SS lines, MM caliper bushings, and steel pistons.[URL]

[CP86SVO]

A soft brake pedal is usually a sign of the fluid getting very hot, to the point of boiling, and it's softening the rubber in the brake hose, which is causing the soft, spongy brake pedal, according to William Mathis in Mustang Performance 2. A higher temperature brake fluid, like Ford HD (550 degree boiling point) or Motul 600 (about 590 degree boiling point) with stainless brake lines should fix this problem.

As for your brake cooling ducts, yes, they have helped, but if they're pointed at the rotor surface, you could risk warping the rotor. Point the end of the duct towards the middle of the rotor instead to prevent this.

All of they guys I know who still use the 73 mm piston calipers/11 inch rotor combination here in Vancouver use Hawk HP Plus pads with pretty good results.

As for the brake dust shields, for the amount you drive it, I would just remove the entire shield; a little water won't really affect the inner seal at all. Again, here in Vancouver, the people who I've removed the shields from their cars haven't had any problems at all, and they drive their cars the same as you.

I can't comment on the brake rotors, as I haven't any experience with slotted rotors at all; I've always used stock FORD rotors on my SVO and 88 LX 5.0 L, and stock Ford or Aimco rotors on others.
I never turn rotors, I only used new rotors to get the maximum thickness and mass for heat dissipation.

HTH WS

[Pat_in_L.A.]

"I used Valvoline synthetic, and it says it's boiiling point is "over 500deg.""

Synthetic brake fluid SUCKS!

It has, what is called by engineers, "a negative thermal compressability ratio". What does that mean? It means that although it won't boil or absorb humidity, it will give you a softer pedal as the fluid temperatures increase.

I learned this the hard way in 1982 at the Long Beach Grand Prix when some vendor talked Toyota into using it on their Celebrity cars. I had 18 cars with spongey pedal complaints after the brake fluid swap. You think you have it bad? Try bleeding the brakes over and over again on 18 cars in 2 hours!

Just go to Castrol GTLMA and report back to me.

[CP86SVO]

I just blipped onto some good info on brake fluid...

check out www.stoptech.com/whitepapers/brakefluid1a.htm

HTH WS

[indiana dave]

Good article... Lots of info.

Btw, What's the HTH WS mean in your sig.?

[CP86SVO]

HTH hope this helps

WS Willie Seto

[gbeaird]

If you are open tracking a car, you should bleed the brakes just before every open track event. Just a little water, and you can have all sorts of brake problems. It doesn't take much water, and brake fluid will suck the water right out of the air. Get it out by thoroughly bleeding the brakes before the event.

Gene Beaird
86 2R SVO
Pearland, Texas