Rotor Replacement Suggestion
10-03-2003, 10:47 AM
#1
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Join Date: Nov 2001
Location: Clearwater, FL
Posts: 338
Rotor Replacement Suggestion
I'm looking at replacing the stock rotors on a 1996 Trans Am, and I'm looking for some suggestions. I don't need to go nuts, but I'd like something that offered a little better performance than stock. Any suggestions?
10-03-2003, 12:07 PM
#2
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Join Date: Jun 2001
Location: Detroit area
Posts: 1,781
Check out Thunder Racings package with the Powerslots and hawk pads.I am real happy with it...Trey is going to come and tell you the slots dont do a thing and are bling.Dont knock it till you try it.
had um hate them got rid of them,got blanks and hawk pads 100%beter
10-03-2003, 03:31 PM
#8
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Join Date: Mar 2002
Location: Louisville, KY, USA
Posts: 422
Just get decent blanks and spend the money you saved on better pads. Autozone's Aimco rotors are 30 each (thereabouts) and work very well. If you want to spend more you can get raybestos or Brembo replacement blanks for $60 each.
10-03-2003, 07:26 PM
#9
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Thread Starter
Join Date: Nov 2001
Location: Clearwater, FL
Posts: 338
The TA is my girl's and she rarely takes the car up to 3000 RPM, so I don't need to go nuts with the expensive slotted roters. The $30 rotors at Autozone are worth a damn? She's just getting some serious shake when stopping, the rotors are probably too wasted to machine straight again.
10-03-2003, 07:41 PM
#10
On permanent vacation
Join Date: Aug 2003
Location: Michigan is a decent state.
Posts: 520
Originally posted by joeSS97
Check out Thunder Racings package with the Powerslots and hawk pads.I am real happy with it...Trey is going to come and tell you the slots dont do a thing and are bling.Dont knock it till you try it.
Check out Thunder Racings package with the Powerslots and hawk pads.I am real happy with it...Trey is going to come and tell you the slots dont do a thing and are bling.Dont knock it till you try it.
I think I've had enough expierence and first hand data to justify my position.
Can I ask your qualifations? any more proof than "it felt like i stopped faster"
here is my explanation and justification. I'd love to hear yours (honestly, no sarcasm)
http://web.camaross.com/forums/showt...ghlight=rotors
http://web.camaross.com/forums/showt...ghlight=rotors
Here it is all jumbled up in one post from another forum:
Slots and cross drills are not for cooling and provide a very minimal amount of cooling. the majority of the cooling comes from the vents and the size of the rotor and its thickness. The vents can create some pretty nice air flow inside and around the rotor.
The slots and holes do not have a significant amound or air flow around them. Althought this can be debated since real world air flow in that region is a stab in the dark on a good day. It is pretty well agreed upon that those slots and hole do very little for cooling though. The air in there is almost stationary when compared to the vents and the air along side the rotor (particularly outboard braking plate). The air is flowing from left to right (when looking at the rotor head on- looking at the wheel stud holes). Very little air is flowing from the inboard to ourboard rotor plates or vice versa. The air inside the vent holes is pretty stagnant in there compared to the air along the outboard rotor and air in the vents. The vents can work because they utilize the air flowing from left to right, not "through" and "into" the rotor. They are like a little cinfrifical fan..
Plus the amount of surface area has probobly trippled or quadrroopled with these vents. here is now two more surfaces in the middle (effectivly doubling surface area right there) and the additional surface area of the 4 surfaces of the vent.
If i had to guess, I bet that there is VERY little air flow inside the wheel well t begin with- and particualry under our cars relative to most other cars. The low stance and air dam really should do a good job of making sure air doesn't go crazy under there.
As far as breaking power goes, they will reduce your breaking power since a good percentage of your friction is lost. i'd guess around 10% of your pad is no longer creating any friction.
These slots and holes are for releasing gasses that build up under high heat and pressure of panic stops (or aggresive driving). With the pads used in todays vehicles, there are EXTREMLY little gasses prodeced, if any at all. If there is any, its prety much negligable. The only time you have any chance of producing gasses is durring competative autocrossing or road racing (not street racing)- or if you have $7 napa pads!
As far as drilling your own (did i read that somewhere?), I am pretty sure.
a. slotted/cross drilled rotors are thicker/stronger than OEM
b. it has to be PEFRECTLY balanced or life will be ****ty
c. It is extremely hard to drill evenely, effectively and safely.
You have to drill correctly (dont crack the rotor!), symetrically (dont throw it off balance) and you CANT HIT ANY OF THE VENTS!. doing the last two tegether will prove to be a challenge since most rotors have a prime number (hence odd) number of vents. This is done purposely do make as FEW LINES of symetry as possible. Less lines of symetry = less noise for a mutitude of reasons over my head, I didn't really get it when my boss explained it to me. So drilling symeticrially and not hitting nonsymetrical vents might prove to be a mathematical nightmare!
In this long winded responce, i kind hoped to get at this. Slotted and cross drilled are realy only good for appearance mods. If anything they will probobly warp and/or crack faster with all things being equal such as plate thickness and diamter- and i going to go out on a limb and say they are.
Personally, I am going to try some stuff out and see what happens. Although it probobly wont be as cost effective as the LS1 or C5 brake upgrade- I am drawn to doing it. I guess my natural curriousity is doing it to me. I am going to attempt to make two ducts (one for each front rotor) to cool the inboard rotor. Kind of like "ram air" to the rotors if you will. I will do some measurements to see how well it stops- although i cant really guarntee accuraccy. I am also going to swap in the most exensive/best brake fluid i can find and see what that does- maybe even find some crazy way of cooling it Then i'll probobly just do the LS1 brake upgrade and get some Hawk Pads. Thats probobly the best bang for the buck.
With the above said, a set of high quality "blank" vented (99% are vented now a days) rotors would probobly suit you best for your application. Who makes them or what they cost is beyond me. I was just doing some late night LS1 reading tonight and stumbled across this. I would't worry too much though about the car, warped rotors are pretty common on LS1's. Hell a drive through a puddle/car wash after a long drive can do it.
Mark please dont (and I hope you didn't) take this as an attack on you or your buisness, merchandise or expertise. I was really hesitant to type all of this seeing how you are a new supporter of this website. I am really all for supporters of this site and encourage/sugg
Other factors- Slots and cross drilling will make the rotor lighter- so it has less thermal mass. less mass = more brake fade. Drive a fully loaded truck and try to stop on a downhill. You will quickly realize brake fade is a bad thing!
Tires: Stickier tires will allow for a greater braking force without locking up the wheel or engaging ABS ( a very good thing, basically extend your max braking capabilities).
Front vs rear brakes: in most vehicles about 60% of the vehicle's weight is up front . About 70% when the car nose dives. That is why front brakes are the big problem. It is entirely possible to have the rear brakes lock up since there is almost no weight on them and have the front brakes stuggling. Just another reason to shoot for better weight distribution.
Shocks/supsnsion: stiffer suspension means less nose dive which means less "work" for the front brakes. Better weight distribution under braking.
Pads: Cheap effective way to increase braking capabilities. Certian pads work better under extreme conditions and poorly under normal conditions. Stay away from these unless you road race and heat them up before you go out there if possible. It would be extremely difficult to attain these conditions driving normally.
Brake ducts: As I explained above, a great way to reduce brake fade and VERY effective- especialy in lowered cars or cars with air dams such as F-bodies. The Z06 is equipped with a brake duct and stops a lot better than the standard C5. It also has better tires and less weight.
Taken from Baer's website FAQ directly:
"Although crossdrilling and/or slotting will provide a welcome path to expend any gasses when and if they develop, it is primarily a visual enhancement behind today’s often wide-open wheel designs.
Crossdrilling offers the greatest gas relief pathway, but creates potential “stress risers” from which cracks can occur. Baer’s rotors are cast with crossdrilling in mind, from the material specified, to curved vanes, behind which the holes are placed to minimize potential crack migration. Slotted surfaces are what Baer recommends for track only use. Slotted only rotors are offered as an option for any of Baer’s offerings."
The following information was taken directly off Wilwood's FAQ:
"Rotors are drilled to reduce rotating weight, an issue near and dear to racers searching for ways to minimize unsprung weight. Drilling diminishes a rotor's durability and cooling capacity.
Slots 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. Drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood has a large selection of drilled and slotted rotors for a wide range of applications. "
Rain stopping:
Doesn't matter, you do not have enough traction between the road and the tire. You will lock your wheels/tires up very easily. there will be no heat fade issue or an issue with the caliper not being strong enough. Wheel lockup occurs when the negative force of the friction is greater than the force of friction between the road and the ground. (F of friction = coefficient of friction x normal force (or weight on the wheel for this case). Since there is SUCH a small co-efficient of friction b/t the wet road and tire- F of friction is very small= and hence easy lockup.
So no, cross drilled wont help you in the rain. Hell I'd be surprised if water even lasted on the rotor, that thing gets damn hot damn quick- even if you aren't using the brakes the rotor and pads are still rubbing.
Its like putting a 10 sec car on 4 skinnies and then turning up the boost. Its not the power that’s the problem.
Fins:
Bullet style fins are best as a generalization- directional help a bit too.
Rear Brakes:
Rear brakes wont help much unless the car is very stiff. When you prevent nose dive you can actually start utilizing the rear brakes (keep the weight back there! not up front! split up the work load!)
Warping:
Stay out of puddles. Don’t ride the brakes. Slotted and cross drilled wont help your cause.
The slots and holes do not have a significant amound or air flow around them. Althought this can be debated since real world air flow in that region is a stab in the dark on a good day. It is pretty well agreed upon that those slots and hole do very little for cooling though. The air in there is almost stationary when compared to the vents and the air along side the rotor (particularly outboard braking plate). The air is flowing from left to right (when looking at the rotor head on- looking at the wheel stud holes). Very little air is flowing from the inboard to ourboard rotor plates or vice versa. The air inside the vent holes is pretty stagnant in there compared to the air along the outboard rotor and air in the vents. The vents can work because they utilize the air flowing from left to right, not "through" and "into" the rotor. They are like a little cinfrifical fan..
Plus the amount of surface area has probobly trippled or quadrroopled with these vents. here is now two more surfaces in the middle (effectivly doubling surface area right there) and the additional surface area of the 4 surfaces of the vent.
If i had to guess, I bet that there is VERY little air flow inside the wheel well t begin with- and particualry under our cars relative to most other cars. The low stance and air dam really should do a good job of making sure air doesn't go crazy under there.
As far as breaking power goes, they will reduce your breaking power since a good percentage of your friction is lost. i'd guess around 10% of your pad is no longer creating any friction.
These slots and holes are for releasing gasses that build up under high heat and pressure of panic stops (or aggresive driving). With the pads used in todays vehicles, there are EXTREMLY little gasses prodeced, if any at all. If there is any, its prety much negligable. The only time you have any chance of producing gasses is durring competative autocrossing or road racing (not street racing)- or if you have $7 napa pads!
As far as drilling your own (did i read that somewhere?), I am pretty sure.
a. slotted/cross drilled rotors are thicker/stronger than OEM
b. it has to be PEFRECTLY balanced or life will be ****ty
c. It is extremely hard to drill evenely, effectively and safely.
You have to drill correctly (dont crack the rotor!), symetrically (dont throw it off balance) and you CANT HIT ANY OF THE VENTS!. doing the last two tegether will prove to be a challenge since most rotors have a prime number (hence odd) number of vents. This is done purposely do make as FEW LINES of symetry as possible. Less lines of symetry = less noise for a mutitude of reasons over my head, I didn't really get it when my boss explained it to me. So drilling symeticrially and not hitting nonsymetrical vents might prove to be a mathematical nightmare!
In this long winded responce, i kind hoped to get at this. Slotted and cross drilled are realy only good for appearance mods. If anything they will probobly warp and/or crack faster with all things being equal such as plate thickness and diamter- and i going to go out on a limb and say they are.
Personally, I am going to try some stuff out and see what happens. Although it probobly wont be as cost effective as the LS1 or C5 brake upgrade- I am drawn to doing it. I guess my natural curriousity is doing it to me. I am going to attempt to make two ducts (one for each front rotor) to cool the inboard rotor. Kind of like "ram air" to the rotors if you will. I will do some measurements to see how well it stops- although i cant really guarntee accuraccy. I am also going to swap in the most exensive/best brake fluid i can find and see what that does- maybe even find some crazy way of cooling it Then i'll probobly just do the LS1 brake upgrade and get some Hawk Pads. Thats probobly the best bang for the buck.
With the above said, a set of high quality "blank" vented (99% are vented now a days) rotors would probobly suit you best for your application. Who makes them or what they cost is beyond me. I was just doing some late night LS1 reading tonight and stumbled across this. I would't worry too much though about the car, warped rotors are pretty common on LS1's. Hell a drive through a puddle/car wash after a long drive can do it.
Mark please dont (and I hope you didn't) take this as an attack on you or your buisness, merchandise or expertise. I was really hesitant to type all of this seeing how you are a new supporter of this website. I am really all for supporters of this site and encourage/sugg
Other factors- Slots and cross drilling will make the rotor lighter- so it has less thermal mass. less mass = more brake fade. Drive a fully loaded truck and try to stop on a downhill. You will quickly realize brake fade is a bad thing!
Tires: Stickier tires will allow for a greater braking force without locking up the wheel or engaging ABS ( a very good thing, basically extend your max braking capabilities).
Front vs rear brakes: in most vehicles about 60% of the vehicle's weight is up front . About 70% when the car nose dives. That is why front brakes are the big problem. It is entirely possible to have the rear brakes lock up since there is almost no weight on them and have the front brakes stuggling. Just another reason to shoot for better weight distribution.
Shocks/supsnsion: stiffer suspension means less nose dive which means less "work" for the front brakes. Better weight distribution under braking.
Pads: Cheap effective way to increase braking capabilities. Certian pads work better under extreme conditions and poorly under normal conditions. Stay away from these unless you road race and heat them up before you go out there if possible. It would be extremely difficult to attain these conditions driving normally.
Brake ducts: As I explained above, a great way to reduce brake fade and VERY effective- especialy in lowered cars or cars with air dams such as F-bodies. The Z06 is equipped with a brake duct and stops a lot better than the standard C5. It also has better tires and less weight.
Taken from Baer's website FAQ directly:
"Although crossdrilling and/or slotting will provide a welcome path to expend any gasses when and if they develop, it is primarily a visual enhancement behind today’s often wide-open wheel designs.
Crossdrilling offers the greatest gas relief pathway, but creates potential “stress risers” from which cracks can occur. Baer’s rotors are cast with crossdrilling in mind, from the material specified, to curved vanes, behind which the holes are placed to minimize potential crack migration. Slotted surfaces are what Baer recommends for track only use. Slotted only rotors are offered as an option for any of Baer’s offerings."
The following information was taken directly off Wilwood's FAQ:
"Rotors are drilled to reduce rotating weight, an issue near and dear to racers searching for ways to minimize unsprung weight. Drilling diminishes a rotor's durability and cooling capacity.
Slots 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. Drilling and slotting rotors has become popular in street applications for their pure aesthetic value. Wilwood has a large selection of drilled and slotted rotors for a wide range of applications. "
Rain stopping:
Doesn't matter, you do not have enough traction between the road and the tire. You will lock your wheels/tires up very easily. there will be no heat fade issue or an issue with the caliper not being strong enough. Wheel lockup occurs when the negative force of the friction is greater than the force of friction between the road and the ground. (F of friction = coefficient of friction x normal force (or weight on the wheel for this case). Since there is SUCH a small co-efficient of friction b/t the wet road and tire- F of friction is very small= and hence easy lockup.
So no, cross drilled wont help you in the rain. Hell I'd be surprised if water even lasted on the rotor, that thing gets damn hot damn quick- even if you aren't using the brakes the rotor and pads are still rubbing.
Its like putting a 10 sec car on 4 skinnies and then turning up the boost. Its not the power that’s the problem.
Fins:
Bullet style fins are best as a generalization- directional help a bit too.
Rear Brakes:
Rear brakes wont help much unless the car is very stiff. When you prevent nose dive you can actually start utilizing the rear brakes (keep the weight back there! not up front! split up the work load!)
Warping:
Stay out of puddles. Don’t ride the brakes. Slotted and cross drilled wont help your cause.
10-04-2003, 01:33 AM
#14
Registered User
Join Date: Feb 2003
Location: CIncinnati, OH
Posts: 21
disclaimer: no first hand experience with upgraded brake rotors.
All I have to say is that after looking at the old Porsche 996TT the engineers over there in germany seem to be a fan of the Drilled rotors, and those people KNOW brakes. Im not saying this is relevent to aftermarket Fbody rotors, but if drilled rotors were archaic technology no longer required by modern brakepads, dont you think these guys would be one of the first to know?
All I have to say is that after looking at the old Porsche 996TT the engineers over there in germany seem to be a fan of the Drilled rotors, and those people KNOW brakes. Im not saying this is relevent to aftermarket Fbody rotors, but if drilled rotors were archaic technology no longer required by modern brakepads, dont you think these guys would be one of the first to know?