Brakes Question
04-07-2007, 03:01 AM
#1
2nd Gear Member
Thread Starter
Join Date: Aug 2006
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Posts: 335
Brakes Question
only 6500 miles and when i brake hard, sometimes pulls to one side with my hand off the wheel. thinking of getting slotted brakes or just pads. any suggestions here?? i think a whole setup is around $700.00
04-07-2007, 10:42 AM
#2
4th Gear Member
Join Date: Feb 2007
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Posts: 1,885
RE: Brakes Question
slotted or drilled wont do anything for performance, just for show as pads no longer need to outgass and slotting and drilling just decrease surface area, and are only useful for racecars..
I say save a few hundred and just get a sick pair of pads!!!!
I say save a few hundred and just get a sick pair of pads!!!!
04-07-2007, 11:22 PM
#6
RE: Brakes Question
Stated by the CrazyAl
Cross-drilled: Years ago (in the 70's) drilling was used to relive a problem called "outgassing", which was caused by poor brake pad formulations. Since the 80s, better brake pad formulation has eliminated the need for drilled rotors. Contrarty to popular belief cross drilling is actually WORSE for heat handling than a solid rotor.The holes arepointing the wrong direction for cooling. Coolingholes need to bein the radial direction (like the spokes on a wheel), not axial. Some racing rotors are cross drilled for weight savings purposes, but these are known to be less durable than solid rotors. "Street" rotors such as the one shown in the above post are cross-drilled simply becacuse it looks cool. Drilled rotors are also prone to cracking. Note that a REAL drilled rotor (one that is drilled for weight savings) looks nothing like the picture shown by the OP post.
Slotted: Slotted rotors were also developed in the early years of performance discbrakes. The theory was that the groove would scrape the pad surface, reducing glazing. Slotted rotors do not warm up any faster than solid rotors. And furthermore, if they did, they would certainly not dissipate heat better. The claim that they come up to temperature faster yet cool more effectively at the same timeis a paradox--whomever wrote that needs to go back to physics class! The slots in a slotted rotor are far too small to have an appereciable effect on surface area or mass, and therefore they have no significant affect on cooling or on weight savings. However, they DO create stress concentrations (areas where cracks can form) on your rotor surface.
Zinc Plating. This is just another fancy name for galvanizing. Sure, you can plate a rotor. However, the first time you brake, the brake pads will scour the plating off the braking surface. You might be able to keep the hub of the rotor from rusting, but you cannot affect the braking area itself.
Read the truth straight from Wilwood: http://www.wilwood.com/Centers/Infor..._answer/07.asp
In their installation notes, they go on to say:
"Caution on drilled rotors: There is a common mis-perception that rotors are drilled to improve cooling. The reduced mass of a drilled rotor will dissipate its retained heat quicker, but it also builds up heat at a much faster rate. The decision to use drilled rotors should be solely based on the merits of the lower rotating and unsprung weight, and not for improved cooling. It is not wise to use drilled rotors in sustained high heat on hard braking tracks unless the team budget affords a high frequency of rotor and brake pad replacement"
Further reading:
Clutches and Brakes by Orthwein
Brake Design and Safety by Limpert
Advanced Brake Technology, published by SAE
Cross-drilled: Years ago (in the 70's) drilling was used to relive a problem called "outgassing", which was caused by poor brake pad formulations. Since the 80s, better brake pad formulation has eliminated the need for drilled rotors. Contrarty to popular belief cross drilling is actually WORSE for heat handling than a solid rotor.The holes arepointing the wrong direction for cooling. Coolingholes need to bein the radial direction (like the spokes on a wheel), not axial. Some racing rotors are cross drilled for weight savings purposes, but these are known to be less durable than solid rotors. "Street" rotors such as the one shown in the above post are cross-drilled simply becacuse it looks cool. Drilled rotors are also prone to cracking. Note that a REAL drilled rotor (one that is drilled for weight savings) looks nothing like the picture shown by the OP post.
Slotted: Slotted rotors were also developed in the early years of performance discbrakes. The theory was that the groove would scrape the pad surface, reducing glazing. Slotted rotors do not warm up any faster than solid rotors. And furthermore, if they did, they would certainly not dissipate heat better. The claim that they come up to temperature faster yet cool more effectively at the same timeis a paradox--whomever wrote that needs to go back to physics class! The slots in a slotted rotor are far too small to have an appereciable effect on surface area or mass, and therefore they have no significant affect on cooling or on weight savings. However, they DO create stress concentrations (areas where cracks can form) on your rotor surface.
Zinc Plating. This is just another fancy name for galvanizing. Sure, you can plate a rotor. However, the first time you brake, the brake pads will scour the plating off the braking surface. You might be able to keep the hub of the rotor from rusting, but you cannot affect the braking area itself.
Read the truth straight from Wilwood: http://www.wilwood.com/Centers/Infor..._answer/07.asp
In their installation notes, they go on to say:
"Caution on drilled rotors: There is a common mis-perception that rotors are drilled to improve cooling. The reduced mass of a drilled rotor will dissipate its retained heat quicker, but it also builds up heat at a much faster rate. The decision to use drilled rotors should be solely based on the merits of the lower rotating and unsprung weight, and not for improved cooling. It is not wise to use drilled rotors in sustained high heat on hard braking tracks unless the team budget affords a high frequency of rotor and brake pad replacement"
Further reading:
Clutches and Brakes by Orthwein
Brake Design and Safety by Limpert
Advanced Brake Technology, published by SAE
