Brake Dust - It's driving me nuts!!!!

[Sox]

Originally Posted by blueoval

Whether it's true or not, I wouldn't want to be the one to be the test pilot to prove or disprove the point.

The way I see it, dust covers are there to 'contain' dust particles getting onto the rims. As for them contributing to additional heat containment for braking efficiency, air flow is crucial for brakes to rid built up heat from the brake calipers and to maintain their performance power under duress.

When the car is moving, the air is directed from front to rear, effectively pushing air flow in this direction most of the time. In its moving state, the dust protectors do just that, protect against brake dust getting onto your rims during the cars movement.

Only when the car is stationary will there be a significant increase in heat with dust protectors on after the car has had it's braking capabilities measured. This additional heat could be considered insignificant of the car is left stationary for a long period of time. However if the car is used shortly after a run, the added heat will be there but unless you are doing a lot of brake work towing straight away after a prolonged stop, it will be insignificant also.

Again, this is what I think using my limited logic of reason and by no means is this to be taken as gospel. I am happy to be corrected.

The fact that dust shields reduce air flow to the brake system is just that, fact.
This has been understood for as long as I can remember.

I'm not quite sure why Ronwest is questioning this.

I will also go on to say that there will be differences when the car is moving to. The biggest differences IMO.
Think of it this way, the shield is restricting air flow through the wheel. Much of the cool air the brakes rely on will come from airflow through the wheel.
If this is reduced when using shields, then naturally brake cooling is reduced.

This is really basic stuff.

Also, as I've repeatedly pointed out, it may not effect 95% of users, however it will effect some. That's a fact.

What happens when you reduce the airflow through the radiator?
Then engine may overheat under some more extreme conditions.

[blueoval]

Im not going to discredit what you are saying Rick. You make valid points. I agree, air needs to go somewhere when moving, if there is a shield in the way, then it makes it harder for heat to dissipate faster. But what would be the % of that as a guess? 5%-10% maximum worse case scenario?

Again, it does come down a lot to the purpose of the vehicle. A race car wouldn't have these fitted. A stock 'grandma' style vehicle would to make it easier for the owner to clean the car. Would the grandma car be affected less in braking performance with these fitted? I highly doubt it, but could be due to her/his ability to drive the car within the conditions they are comfortable with.

While your points are very valid, and I find they have a lot of merit, I still think the affect would be minimal for 97% of drivers base on capability, driving style and other factors as you say, and only a very small percentage would be affected if at all any.

[ronwest]

Originally Posted by Sox

The fact that dust shields reduce air flow to the brake system is just that, fact.
This has been understood for as long as I can remember.

I'm not quite sure why Ronwest is questioning this..

We're not actually in disagreement about shields reducing airflow.

It's obvious that they do.

My question is about the degree of influence that has on brake fade.

Certainly some influence but I'd contend that if you're braking to the point of brake fade, dust shields are the least of your problems.

[Cam]

Originally Posted by lockieoc

Welcome to the world of brake pads.
No matter what you want out of a brake pad there is always going to be a trade off.
If you want a performance pad then your going to have to put up with some noise a fair bit of dust.
If you want a clean pad then your going to have to put up with some reduced performance.

This
+
If you want cleaner rims keep the dust covers on, if you want to be sure the brakes are getting maximum cooling, then take them off!

I've got Competition Pads on my AP's with no dust covers, they make lots of dust, don't brake well when cold, and can be noisy..
Does a run through the mountains make up for this? Yes!

Horses for Courses...

[Sox]

Originally Posted by blueoval

Im not going to discredit what you are saying Rick. You make valid points. I agree, air needs to go somewhere when moving, if there is a shield in the way, then it makes it harder for heat to dissipate faster. But what would be the % of that as a guess? 5%-10% maximum worse case scenario?

That would depend on the style of shields.
Some are quite small, and some fully enclose the rear of the rim, 100% sealed.
I would think 100% sealed would reduce direct air flow to the brake system by as much as 35% or more.
Sure, the smaller ones may only reduce air flow by 5%-10% like you say.

Even so, a car which is already border line, will be pushed over the edge even by small amounts. Maybe literally.

Again, it does come down a lot to the purpose of the vehicle. A race car wouldn't have these fitted. A stock 'grandma' style vehicle would to make it easier for the owner to clean the car. Would the grandma car be affected less in braking performance with these fitted? I highly doubt it, but could be due to her/his ability to drive the car within the conditions they are comfortable with.

While your points are very valid, and I find they have a lot of merit, I still think the affect would be minimal for 97% of drivers base on capability, driving style and other factors as you say, and only a very small percentage would be affected.

This is what I've said all along.

[ronwest]

Originally Posted by Sox

This is what I've said all along.

So, we actually do agree

[Sox]

Originally Posted by ronwest

We're not actually in disagreement about shields reducing airflow.

It's obvious that they do.

My question is about the degree of influence that has on brake fade.

Certainly some influence but I'd contend that if you're braking to the point of brake fade, dust shields are the least of your problems.

Ok, we're getting somewhere.

On a recent trip around Victoria towing a caravan, myself, and my folks following with their rig, experienced brake fade.

My car is a AU XR8 220 with Tickford brakes, of which I replaced the pads with Bendix HD's before leaving.

My folks have a Territory with standard brakes, also replacing the pads with Bendix HD before leaving.

We were each towing a ~1200kg caravan.

For 90% of the trip, the brakes worked just fine and dandy, however, there were 2 occasions where we both experienced brake fade.
Once was approaching Woolongong, the other time was going through the snowys.

Neither of us were in any danger, however both needed considerably higher pedal pressure as we approached the bottom of each respective mountain.
My folks mentioned their brakes smelling somewhat.

Neither of us have dust shields.
How do you think shields would have effected the above scenarios?

My point being, sometimes, some people, in some situations will experience brake fade and there is no problem. It's just the nature of the beast.
Dust shields in these cases will not not help.

[blueoval]

I haven't seen the full size covers before, just the smaller ones hiding the disc and caliper. A full sized one will be like fitting a moon disc to the rim.

I think there are a lot of factors to consider with this subject and while most will get away with having covers, some minorities won't due to a number of possible reasons.

If it were me, I would get rid of them as I want the best braking performance possible and if it makes only 5% difference in braking ability, thats good enough for me.

However my dad is a slow driver and he prefers to have covers on his car, and it matters not. But if I were to drive his car the way I drive mine, I am sure there will be a difference of some description.

[Sox]

Originally Posted by ronwest

So, we actually do agree

If you go back to post #17, you'll see that.

[Sox]

Originally Posted by blueoval

I haven't seen the full size covers before, just the smaller ones hiding the disc and caliper. A full sized one will be like fitting a moon disc to the rim.

I think there are a lot of factors to consider with this subject and while most will get away with having covers, some minorities won't due to a number of possible reasons.

If it were me, I would get rid of them as I want the best braking performance possible and if it makes only 5% difference in braking ability, thats good enough for me.

However my dad is a slow driver and he prefers to have covers on his car, and it matters not. But if I were to drive his car the way I drive mine, I am sure there will be a difference of some description.

I'm the same, and so are my folks, as yours.
However as you can see from my last post, even my folks had brake fade under a certain condition.

[ronwest]

Originally Posted by Sox

How do you think shields would have effected the above scenarios?

I don't know. .0001% worse? 99% worse?

Originally Posted by Sox

My point being, sometimes, some people, in some situations will experience brake fade and there is no problem. It's just the nature of the beast.
Dust shields in these cases will not not help.

Agreed again. We are doing well, lol. But they may not hinder to any significant factor, either.

I have a brother who lives in Glen Innes. We go down there 5 or 6 times per year. Since the landslides at Cunninghams Gap (12 months ago during floods) the chances of not getting caught behind a truck doing 10 -15kph downhill for a few kilometres is very slim.

Following a truck + 20 or 30 cars down the gap, I've had brake fade on my AU without shields and I've had no brake fade on my FG with shields.

We're only debating degree which as we both know can change with circumstances. I absolutely accept that shields will have some
influence on brake fade. IMO it won't be much.

Anyhoo, I've had my say. Happy to read replies but I don't think there's much more I can contribute.

[blueoval]

I think we are all seeing different sides of the spectrum here and I do not believe there is a right or wrong answer to this subject.

It's down to each individual, their driving habits, vehicle type, road/traffic conditions, circumstances of the trip, brake condition and setup, etc.


Sure the will be some heat blockage with shields on, but to what extent will it affect braking? refer to above.

Will it make a difference in braking ability having shields on? refer to above

Will a shield stop brake dust? Mostly, but it all depends on the above too.

Will not having shields fitted benefit my car? again, refer above.

I cannot contribute further to this discussion either. But I can say it is interesting seeing it from others view points and getting their outlook on it.

[Sox]

Originally Posted by ronwest

I don't know. .0001% worse? 99% worse?

Me neither, but we all know it is worse.

Agreed again. We are doing well, lol. But they may not hinder to any significant factor, either.

But then again, they might.
I've heard numerous reports over the last 20 odd years of such things, from people within the industry (Yes, I have worked in the auto industry).

I have a brother who lives in Glen Innes. We go down there 5 or 6 times per year. Since the landslides at Cunninghams Gap (12 months ago during floods) the chances of not getting caught behind a truck doing 10 -15kph downhill for a few kilometres is very slim.

Following a truck + 20 or 30 cars down the gap, I've had brake fade on my AU without shields and I've had no brake fade on my FG with shields.

Ah, but you're comparing apples with oranges here.
FG's have much more powerful brakes than AU1, and reasonably more powerful than AU2/3.
Need to take into account pad differences too (if there is any).
Lots of variables, least of all different cars.

We're only debating degree which as we both know can change with circumstances. I absolutely accept that shields will have some
influence on brake fade. IMO it won't be much.

Anyhoo, I've had my say. Happy to read replies but I don't think there's much more I can contribute.

No problem, I said we should agree to disagree a page or so back.
It's all good.

[prn31]

No one has mentioned that these dust shields are fuggin ugly...

Before I owned a Falcon I must admit I didn't know that they were. All the cars I've owned before (Alfas, Hondas, Volvos, etc) never had them!

On the first AUII Fairmont it was the first thing my mechanic took off, and on the second (AUIII Fairmont V8) they weren't there, thank goodness!

I always thought that AUI Fairmonts with 15 inch alloys had hubcaps -because you couldn't see through to the brake disc. To me that is just dumb.

Even cars today with hubcaps (except those super economical hybrids) have ventilation holes to aid brake cooling.

I thought the whole point with alloy wheels was light weight and heat dissapation....

Back to original poster and his brake dilemma. I've just bought for my Fairmont AUIII a set of DBA slotted rotors and Ferodo GP2 pads. Yes, I know good first choice, not so good second. But I've used Ferodo DS in my race car with good results and I thought they were preferable to Bendix that were the only ones on offer at the auto accessory shop I went to. They squeal, so I guess I need to put some antisqueal grease on them. Don't know about brake dust yet - too new, but I hope they start to feel a bit better than they currently do. I will be towing about 1,300kg with them so I need strong brakes.

[mik]

i took my shields off to get any extra bit of cooling i could on mine, but i have noticed doing bed in procedure for new rotors/ pads even without the shields 8 hard stops from 60 kph will have them turning blue stinking, a bit sorry i took them off really, tempted to putem back on and just take them off for long distance towing duties, for a daily they seem to have little impact.
i usually chuck it back a cog or two if going down a long steep decent to take a bit of stress off the brakes towing or not.

[blueoval]

Originally Posted by prn31

No one has mentioned that these dust shields are fuggin ugly...

Before I owned a Falcon I must admit I didn't know that they were. All the cars I've owned before (Alfas, Hondas, Volvos, etc) never had them!

On the first AUII Fairmont it was the first thing my mechanic took off, and on the second (AUIII Fairmont V8) they weren't there, thank goodness!

I always thought that AUI Fairmonts with 15 inch alloys had hubcaps -because you couldn't see through to the brake disc. To me that is just dumb.

Even cars today with hubcaps (except those super economical hybrids) have ventilation holes to aid brake cooling.

I thought the whole point with alloy wheels was light weight and heat dissapation....

Back to original poster and his brake dilemma. I've just bought for my Fairmont AUIII a set of DBA slotted rotors and Ferodo GP2 pads. Yes, I know good first choice, not so good second. But I've used Ferodo DS in my race car with good results and I thought they were preferable to Bendix that were the only ones on offer at the auto accessory shop I went to. They squeal, so I guess I need to put some antisqueal grease on them. Don't know about brake dust yet - too new, but I hope they start to feel a bit better than they currently do. I will be towing about 1,300kg with them so I need strong brakes.

I agree, they are definitely ugly. I have seen them on the EF fairmont factory rims and they look like crap. Some people put leave them on or put them on others don't. Horses for courses.

I was led to believe the alloy wheels not only helped with looks but also being lighter weight than steel wheels helped economy a bit. as for heat dissipation, alloy doesn't conduct heat as bad as steel and if designed right can aid with additional heat removal depending on driving style, road/car conditions etc. But we could go on about this subject for ages so I wont go into it.

[Sox]

Originally Posted by blueoval

I was led to believe the alloy wheels not only helped with looks but also being lighter weight than steel wheels helped economy a bit.

And handling, less unsprung weight....

[Uncle_Ken]

What about this kind of thing?



Brake cooling, pushing air onto the disk? Does this work?

UK

[Sox]

Originally Posted by Uncle_Ken

What about this kind of thing?

image

Brake cooling, pushing air onto the disk? Does this work?

UK

Should do, if set up right.
Many modern cars have pretty good cooling directed to the brake system as standard.

[lockieoc]

Ok so many of you are missing the point of the "dust" covers. The main reason they are there is because Ford are to cheap to pain the hubs so the have the covers there to hide any unsightly rust.
The older EF/EL series cars with the proper "dust" covers were there to do just that, stop dust.

Now do dust covers affect brake temperatures?

later models (AU - on): Doubt you would ever notice it. The fact the the air is draw into the rotor from the back means its sucking the in the air that runs from underneath the car, so reduced air flow isn't an issue you may only see a minute change in the level of heat dissipation but not something that you would notice unless you were on a race track.

Earlier Models (EF/EL): Definitely. These covers drastically reduce heat dissipation turning the wheel into an oven when towing through some twist steep mountain runs or on long continues braking situations. The disc will begin to heat, the heat then will begin to be transferred into the pads (the less pad materiel the faster this will happen) which causes the pads to cook which then let of a gas which forms almost a barrier between the pad and disc reducing almost all friction resulting in brake fade.

[Vincenzo]

Greetings

I'm driving round in the tropical north most of the year. About two months ago I fitted EBC Redstuff pads with drilled and slotted discs. The first day extremely quiet then they started to squeal for about six weeks (1,000 km). Quiet now.

I have said this previously and I will say it again - they grip like a saltie grabbing a feral pig from the water's edge from cold right through to approx 800C and now that they appear to be bedded in, little to no dust.


Vincenzo

[Day-mow]

Originally Posted by prn31

No one has mentioned that these dust shields are fuggin ugly...

Amen.
no dust shields. wash your car more. problem solved