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Brake problems by 86Ferrari
Started on: 08-15-2016 12:39 PM
Replies: 45 (981 views)
Last post by: 86Ferrari on 08-25-2016 08:46 AM
hyperv6
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Report this Post08-21-2016 03:17 PM Click Here to See the Profile for hyperv6Send a Private Message to hyperv6Edit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by sardonyx247:

When I went to drilled and slotted rotors all my brake fade went away, so there is some truth to it. Drilled and or slotted = more surface area for heat to dissipate, and less surface area on the pads for more friction. Don't knock it until you tried it. I wouldn't say it stopped quicker, but the fade went away.



I have tried it. I also have been in many tech semiars from major brake suppliers that tell us they are for cosmetic use only.

In fact the head of EBC said he will never sell a drilled rotor because they are problem prone and they do not increase cooling in anyway. He said on a street car the heat sink effect of the extra metal to absorbe and transfer the heat is much more effective on a solid rotor. I think he would know something about brakes.

He also added that the reason many companies sell them is to make money nothing else. They are major profit products because people have been duped enough they do not have to make crazy claims. He sells a dimpled one for profit reasons.

Note too that most racing cars use at best a grove-ed J to clean the rotors of debris at best. Look at NASCAR, IMSA, Indy, F1. WEC etc. none use a drilled rotor. In fact many track time places discourage them to due to failures.

At one time organic pads out gassed and they also needed to reduce unsprung weight on cars and this is how they used to do it. No longer do they do this.

Many people still believe it and some companies will try to market it as such but if you dig down and really see what the most potent cars in the world use in racing they no longer drill them.

Here is what Wil Wood brakes has to say. I think they may know a little bit about braking. I deal with them often and never steered me wrong.

Q: What's the difference between slotted and drilled/slotted rotors? Which rotor will be best for my application?
A:

PSlots or grooves in rotor faces are partly a carryover from the days of asbestos pads. Asbestos and other organic pads were prone to “glazing” and the slots tended to help “scrape or de-glaze” them. Also, cross-drilling and/or slotting the rotor for racing purposes was beneficial by providing a way to expel the gasses created when the bonding agents employed to manufacture the pads began to break down at extreme temperatures. This condition is often referred to as “outgassing.” When it does occur, the driver still has a good firm brake pedal, but a significant reduction in friction. Normally this only happens at temperatures witnessed in racing. However, with today’s race pad technology, “outgassing” is no longer a concern with pads designed for racing.

So in the final analysis, drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood provides rotors slotted, drilled or plain. For most performance applications, slotted is the preferred choice. With certain pad material, slotting can help wipe away debris from between the pad and rotor as well as increasing the coefficient of friction between the rotor and the pad. A drilled rotor provides the same type of benefit, but is more susceptible to cracking under severe usage; however, for street and occasional light duty track use, they will work fine. For more severe applications, we recommend slotted rotors.

http://www.wilwood.com/TechTip/TechFaqs.aspx

Odds of your brake improvment were more due to better pads or just rotors in better condition. Pads get old and degrade at a slow rate. Even the same pad new will not fade as easily do to less heat cycles and more material.

I would read up on reliable tech info. Don't knock it until you tried i

Also note slotted do have some benefits but not in cooling. They are the only real true upgrade if any,

But I can't complain as if people still want to pay more for drilled my profit sharing makes me happy either way. I am honest with a customer but if they choose to still buy them for performance that is all on my profit sharing. I tell them you want looks or better performance and just let them choose.
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86Ferrari
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Report this Post08-24-2016 03:23 PM Click Here to See the Profile for 86FerrariClick Here to Email 86FerrariSend a Private Message to 86FerrariEdit/Delete MessageReply w/QuoteDirect Link to This Post
Plenty of rabbit chasing been going on here in my absence. Update on my original problem. I replaced all 4 rubber lines with zero improvement after the fact. Not to say they probably didn't need replacing as all but 1 looked like the original vintage 1986 lines. Pedal is still soft and braking not improved. I think many of you missed that point from my original post when the talk of wheels and tires and such took place and kind of took over this thread. None of that will cause a soft pedal to my knowledge. Odd thing that I noticed after bleeding the lines this time that I didn't really notice before is that bleeding front and back only drained down the front reservoir of the master cylinder. I didn't really catch that till I was all done and I got to thinking about it. I think I had the same outcome with the original master cylinder also (remember I originally thought it was bad therefore replaced it first). Does this make any sense to anyone? The lines are ran into and out of it as they should and to its corresponding wheel as it should. One of my original thoughts was that the proportioning valve was bad but had someone here say that it wasn't possible but I'm leaning back that way. If it had an internal crack could it be feeding fluid from only one reservoir to all 4 wheels? Seems unlikely but??
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Report this Post08-24-2016 04:11 PM Click Here to See the Profile for jaskispyderSend a Private Message to jaskispyderEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 86Ferrari:


Only one part of the master cylinder drained when you bleed all the lines???

http://www.fiero.nl/forum/Forum1/HTML/094252.html

[This message has been edited by jaskispyder (edited 08-24-2016).]

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Patrick
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Report this Post08-24-2016 04:17 PM Click Here to See the Profile for PatrickClick Here to Email PatrickSend a Private Message to PatrickEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 86Ferrari:

One of my original thoughts was that the proportioning valve was bad but had someone here say that it wasn't possible but I'm leaning back that way.


Here's another thread that might be helpful for you... That Combination Proportional Valve

 
quote
Originally posted by Fierobsessed:

For a start, heres what the valve is like in its normal state. I left out the details of the tube mounting cavity and the warning switch, cause im lazy.


[This message has been edited by Patrick (edited 08-24-2016).]

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theogre
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Report this Post08-25-2016 01:09 AM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by 86Ferrari:
If it had an internal crack could it be feeding fluid from only one reservoir to all 4 wheels? Seems unlikely but??
Some OE tanks, wall between front and back should have a slot from top to about 1/2 way down. Is because tank is short for clearance like sun roof Fiero.

Could be you failed to "bench bleed" the MC for whatever reason and still have air trapped.
See my Cave, Bleeding MC notes and Quick Take-up notes

Otherwise no way that front tank is sucked fluid by rear brake. Except One...

Try loosening MC mount a bit, use something thin between booster and mc, the tighten. Too thick and you will have low pedal, even more then now.
If the booster won't return MC to rest, this may help find the problem.
if fix or not, Don't drive like this! This setup is for testing only.

Why?
Rare but possible.... If MC front piston won't return to rest, the piston seals may allow fluid flow for bleeding rear. Front Cup Seals can act as valves and fluid flow can be backward to normal operation.
Maybe more so because QT valve under rear tank may have more flow resistance.

If this helps... booster or pedal have problems.
If booster was replace... someone setup the pin that pushes MC wrong. Correctly setting that pins needs a tool that first measure the MC then act as a gauge to adjust the pin.

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86Ferrari
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Report this Post08-25-2016 08:46 AM Click Here to See the Profile for 86FerrariClick Here to Email 86FerrariSend a Private Message to 86FerrariEdit/Delete MessageReply w/QuoteDirect Link to This Post
I did bench bleed the MC prior to installing it per manufacturers instructions. Any "air in the system" issues I've ever had in the past lead to a soft pedal as I have now but if you kept your foot on the pedal it slowly sank to the floor. (in my experiences anyway). In this instance it is soft to a point but never slips all the way down. And again the symptoms now are exactly as they were when I started this project and to catch everyone up to date I have replaced the MC and all rubber flex lines at the calipers, bench bled MC before installing as well as bleeding all 4 corners (twice now) and had absolutely no change in my situation.
 
quote
Originally posted by theogre:

[QUOTE]Originally posted by 86Ferrari:
If it had an internal crack could it be feeding fluid from only one reservoir to all 4 wheels? Seems unlikely but??
Some OE tanks, wall between front and back should have a slot from top to about 1/2 way down. Is because tank is short for clearance like sun roof Fiero.

Could be you failed to "bench bleed" the MC for whatever reason and still have air trapped.
See my Cave, Bleeding MC notes and Quick Take-up notes

Otherwise no way that front tank is sucked fluid by rear brake. Except One...

Try loosening MC mount a bit, use something thin between booster and mc, the tighten. Too thick and you will have low pedal, even more then now.
If the booster won't return MC to rest, this may help find the problem.
if fix or not, Don't drive like this! This setup is for testing only.

Why?
Rare but possible.... If MC front piston won't return to rest, the piston seals may allow fluid flow for bleeding rear. Front Cup Seals can act as valves and fluid flow can be backward to normal operation.
Maybe more so because QT valve under rear tank may have more flow resistance.

If this helps... booster or pedal have problems.
If booster was replace... someone setup the pin that pushes MC wrong. Correctly setting that pins needs a tool that first measure the MC then act as a gauge to adjust the pin.

[/QUOTE]

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