gts rotors
09-06-2012, 09:22 PM
#31
Drifting
Quick example BMW
" Movit brakes are expensive!
--------------------------------------------------------------------------------
Just got a price quote from the factory for a Z3M...pwnt!
322x32 kit with 4 piston calipers cost 2600 EUR net
342x34 kit with 4 piston calipers cost 3000 EUR net
380x32 kit with 4 piston calipers cost 4000 EUR net
380x32 kit with 6 piston calipers cost 5200 EUR net
Rear brakes
299x24 kit with 4 piston calipers cost 2300 EUR net
"
Looks like it is easy to double the cost on many 928s with just a brake upgrade !
" Movit brakes are expensive!
--------------------------------------------------------------------------------
Just got a price quote from the factory for a Z3M...pwnt!
322x32 kit with 4 piston calipers cost 2600 EUR net
342x34 kit with 4 piston calipers cost 3000 EUR net
380x32 kit with 4 piston calipers cost 4000 EUR net
380x32 kit with 6 piston calipers cost 5200 EUR net
Rear brakes
299x24 kit with 4 piston calipers cost 2300 EUR net
"
Looks like it is easy to double the cost on many 928s with just a brake upgrade !
so you could have 342's + 299's and spend $5,300 eur or $10,600?
A lot of cabbage, but picture this, a sweet somewhat lowered 928, at night, coming down some off-ramp at a good clip, opened exhaust burbling and popping,HID headlights up, and right before turning onto another street, both wheels light up and glow orange as the car slows faster than you thought possible before accelerating away.
At least it doesn't cost to imagine, But even if, with all the best upgrades possible your still way lower than the cost of a lot of average rides and have the best looking and now contemporary 928.
09-06-2012, 09:24 PM
#32
Rennlist Member
that will never happen. usually you need a few laps and starting temps of about 500 degrees, heat soaking the rotors and wheels before things start glowing. 
the street is SO SO different than the track. however, dragging the brakes down from tahoe to sacramento migh work.
the street is SO SO different than the track. however, dragging the brakes down from tahoe to sacramento migh work.
Are those prices PER WHEEL? or does a KIT cover both sides?
so you could have 342's + 299's and spend $5,300 eur or $10,600?
A lot of cabbage, but picture this, a sweet somewhat lowered 928, at night, coming down some off-ramp at a good clip, opened exhaust burbling and popping,HID headlights up, and right before turning onto another street, both wheels light up and glow orange as the car slows faster than you thought possible before accelerating away.
At least it doesn't cost to imagine, But even if still with all the best upgrades possible your still way lower than the cost of a lot of average rides and the best looking and now contemporary 928.
so you could have 342's + 299's and spend $5,300 eur or $10,600?
A lot of cabbage, but picture this, a sweet somewhat lowered 928, at night, coming down some off-ramp at a good clip, opened exhaust burbling and popping,HID headlights up, and right before turning onto another street, both wheels light up and glow orange as the car slows faster than you thought possible before accelerating away.
At least it doesn't cost to imagine, But even if still with all the best upgrades possible your still way lower than the cost of a lot of average rides and the best looking and now contemporary 928.
09-06-2012, 09:29 PM
#33
Rennlist Member
wow!!!! great, lets see the adapters!!!!!!! ill use them too. the rotors are cheap, and good quality. zimmmerman. solid which is fine. slotted is better, but at 80 bucks each, thats great!!
so we need centering rings and drill a couple of holes for the set screws and the adapters. the adapters are the most difficult part because there is not much of change, but you need to bolt the adapter on the spindle with bolts and then mount the calipers on the adapters, which use bolts too! so, there isnt much room for this. Ill believe it when i see it. are you sure he doesnt have an S 85 brake set up, not S4???
mk
so we need centering rings and drill a couple of holes for the set screws and the adapters. the adapters are the most difficult part because there is not much of change, but you need to bolt the adapter on the spindle with bolts and then mount the calipers on the adapters, which use bolts too! so, there isnt much room for this. Ill believe it when i see it. are you sure he doesnt have an S 85 brake set up, not S4???
mk
Mark, Ed Standke (OBehave) is using Cayenne rotors on his '85 track car. He made the "adapters" for the calipers, and then centering rings for the rotors. So, they're actually being used on a track car, right meow. Also, I believe he only paid around $80ish for the front rotors. SO, on a car like mine and his this may well be the cheapest answer IF you already have calipers to swap to.
I have no idea on the fitment of these on an S4 would really need. Which, I suppose is all that matters since it's the car in question. I just figured that this was a "possible" option as well for the S4 cars. Guess not.
I'll take a "solid" rotor every time. Plus, they tend to be cheaper. But they sure aren't as "pretty" I suppose.
I have no idea on the fitment of these on an S4 would really need. Which, I suppose is all that matters since it's the car in question. I just figured that this was a "possible" option as well for the S4 cars. Guess not.
I'll take a "solid" rotor every time. Plus, they tend to be cheaper. But they sure aren't as "pretty" I suppose.
09-06-2012, 09:34 PM
#34
Rennlist Member
You made some good points then contradicted yourself (we have had this discussion before)
Braking is a scientific certainty ------> Turning mechanical energy into heat energy
The best way by far to do that is Ceramic brakes, but next best is larger rotors for a larger surface area to (absorb) and give off the heat. Doesn't matter if it is on the track or the street or going 150 or 35, you are converting mechanical energy to heat, that's all. The cars that stop the quickest have Ceramics, then next best are the largest steel rotors. Pads are also important.
Brake Fade is something more likely to happen on the track and occurs when too much heat overwhelms the entire system -- rotors, pads, calipers, fluid.
I wasn't on a race track when I drove a 360 CS and those brakes were unreal and CERAMIC.
Braking is a scientific certainty ------> Turning mechanical energy into heat energy
The best way by far to do that is Ceramic brakes, but next best is larger rotors for a larger surface area to (absorb) and give off the heat. Doesn't matter if it is on the track or the street or going 150 or 35, you are converting mechanical energy to heat, that's all. The cars that stop the quickest have Ceramics, then next best are the largest steel rotors. Pads are also important.
Brake Fade is something more likely to happen on the track and occurs when too much heat overwhelms the entire system -- rotors, pads, calipers, fluid.
I wasn't on a race track when I drove a 360 CS and those brakes were unreal and CERAMIC.
now, get this....... racing= reality street= dream land.
there is no difference in street set ups vs race set ups for stoppingone time. the heat is easily handled by the set ups as long as the cars are not too heavy and you are not talking race rubber. the tire is the real limitation. i outstop ceramic brakes all the time. skill is most important with braking, if you dont have ABS. if you do, then just push as hard as you can and the system will do the rest. again, the limtation is the tire, not the brake on a one time stop from 100mph to 40mph.
09-06-2012, 09:39 PM
#35
Rennlist Member
Quick example BMW
" Movit brakes are expensive!
--------------------------------------------------------------------------------
Just got a price quote from the factory for a Z3M...pwnt!
322x32 kit with 4 piston calipers cost 2600 EUR net
342x34 kit with 4 piston calipers cost 3000 EUR net
380x32 kit with 4 piston calipers cost 4000 EUR net
380x32 kit with 6 piston calipers cost 5200 EUR net
Rear brakes
299x24 kit with 4 piston calipers cost 2300 EUR net
"
Looks like it is easy to double the cost on many 928s with just a brake upgrade !
" Movit brakes are expensive!
--------------------------------------------------------------------------------
Just got a price quote from the factory for a Z3M...pwnt!
322x32 kit with 4 piston calipers cost 2600 EUR net
342x34 kit with 4 piston calipers cost 3000 EUR net
380x32 kit with 4 piston calipers cost 4000 EUR net
380x32 kit with 6 piston calipers cost 5200 EUR net
Rear brakes
299x24 kit with 4 piston calipers cost 2300 EUR net
"
Looks like it is easy to double the cost on many 928s with just a brake upgrade !
and the 330mm rotors added to the Sbrakes cost about $300 . you get the same function at 1/10 the price, still look cool because you get the big rotor, functionality and you just get race pads for the S brakes!!!
09-06-2012, 10:09 PM
#37
Drifting
i didnt contradict myself. if i did, tell me how. curious.
now, get this....... racing= reality street= dream land.
there is no difference in street set ups vs race set ups for stoppingone time. the heat is easily handled by the set ups .............. the tire is the real limitation. i outstop ceramic brakes all the time. skill is most important with braking, if you dont have ABS. if you do, then just push as hard as you can and the system will do the rest. again, the limtation is the tire, not the brake on a one time stop from 100mph to 40mph.
now, get this....... racing= reality street= dream land.
there is no difference in street set ups vs race set ups for stoppingone time. the heat is easily handled by the set ups .............. the tire is the real limitation. i outstop ceramic brakes all the time. skill is most important with braking, if you dont have ABS. if you do, then just push as hard as you can and the system will do the rest. again, the limtation is the tire, not the brake on a one time stop from 100mph to 40mph.
No matter how many stops you are doing or where they happen, the brakes dissapating the heat are doing the work, kinetic energy into thermal energy.
I already gave you street 1 time stopping distances for
stopping distance 60-0 ;
928S(as I remember)...............................134 ft......... curb weight 3200
Tesla model S sedan.................................108 ft.........curb weight 4600
No magic tires, just turning kinetic energy into heat (and maybe regenerative)
09-06-2012, 10:14 PM
#38
Three Wheelin'
wow!!!! great, lets see the adapters!!!!!!! ill use them too. the rotors are cheap, and good quality. zimmmerman. solid which is fine. slotted is better, but at 80 bucks each, thats great!!
so we need centering rings and drill a couple of holes for the set screws and the adapters. the adapters are the most difficult part because there is not much of change, but you need to bolt the adapter on the spindle with bolts and then mount the calipers on the adapters, which use bolts too! so, there isnt much room for this. Ill believe it when i see it. are you sure he doesnt have an S 85 brake set up, not S4???
mk
so we need centering rings and drill a couple of holes for the set screws and the adapters. the adapters are the most difficult part because there is not much of change, but you need to bolt the adapter on the spindle with bolts and then mount the calipers on the adapters, which use bolts too! so, there isnt much room for this. Ill believe it when i see it. are you sure he doesnt have an S 85 brake set up, not S4???
mk
They are indeed S4 calipers over Cayenne rotors up front, and S4 rotors/calipers in the rear. His car does NOT have the early spindles, this was just so he didn't have to change spindles. I really hope he is willing to sell a couple sets, because it would be great to not have to do the swap for early stuff just to put on S4/GTS calipers on an S.
Whenever he gets around to posting over here I'll let him explain. He cites your Cayenne rotor thread, and Steve Hattori's thread as his inspiration.
09-06-2012, 10:34 PM
#39
Drifting
for further discussion if the Tesla example does not turn on the light there is plenty here
https://rennlist.com/forums/928-foru...e-928-a-3.html
I would say there is 25 ft improvement to be had in ceramics fitted to a 928, 1 stop on the street.
https://rennlist.com/forums/928-foru...e-928-a-3.html
I would say there is 25 ft improvement to be had in ceramics fitted to a 928, 1 stop on the street.
09-06-2012, 11:44 PM
#40
Pro
Join Date: Mar 2004
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No matter how many stops you are doing or where they happen, the brakes dissapating the heat are doing the work, kinetic energy into thermal energy.
I already gave you street 1 time stopping distances for
stopping distance 60-0 ;
928S(as I remember)...............................134 ft......... curb weight 3200
Tesla model S sedan.................................108 ft.........curb weight 4600
No magic tires, just turning kinetic energy into heat (and maybe regenerative)
I already gave you street 1 time stopping distances for
stopping distance 60-0 ;
928S(as I remember)...............................134 ft......... curb weight 3200
Tesla model S sedan.................................108 ft.........curb weight 4600
No magic tires, just turning kinetic energy into heat (and maybe regenerative)
Tire technology has changed in the 30 years between the 928S and the TeslaS.
ABS technology has changed (or been invented) in the same period.
Yes, brakes turn kinetic energy into heat - but it is the tires' grip on the road that drives the braking system.
You kind of acknowledged this with "No magic tires...", but I beg to differ.
If you compare what 2012 R spec tires can do, to what was possible with tires available for a street GT in 1985, "magic" seems ENTIRELY plausible.
09-07-2012, 12:37 AM
#41
Nordschleife Master
It's true! Almost all cars have more brakes than tires. That is, you can lock the tires or make the anti-locks come on as the brakes have more stopping force than the tires can match. Get huge tires? Then get more aggressive brake pads.
I run the S brakes with Hawk Blue pads and brake very aggressively on the track. Even with 245/40/18 DOT competition tires in the front I can still make them skid. I haven't boiled the fluid in maybe 10 years and after that I got a bit more serious about running good DOT 4 fluid and not running pads below 1/4" of material.
That's just one example but not un-typical. What's the net-net? Those giant brakes are about cosmetics on any street car. For track cars it's different but both the car and driver need to be highly serious to really need those 16" carbon fibre rotors.
All that aside, my S rotors look kind of puny behind the open-spoke 18" wheels. The agony!
I run the S brakes with Hawk Blue pads and brake very aggressively on the track. Even with 245/40/18 DOT competition tires in the front I can still make them skid. I haven't boiled the fluid in maybe 10 years and after that I got a bit more serious about running good DOT 4 fluid and not running pads below 1/4" of material.
That's just one example but not un-typical. What's the net-net? Those giant brakes are about cosmetics on any street car. For track cars it's different but both the car and driver need to be highly serious to really need those 16" carbon fibre rotors.
All that aside, my S rotors look kind of puny behind the open-spoke 18" wheels. The agony!
09-07-2012, 12:12 PM
#42
Drifting
I made the point in that longer discussion that F1 cleared up the tire part of this by improving braking performance while using skinnier less grippy tires.
But I agree, all things help, ABS helps and wider, stickier tires help, but marginally. Bigger brakes work better at dissipating heat and Ceramics work better still.
some standard vs ceramic comparisons;
Ferrari 360 -------- 117ft
Ferrari 360 CS ---- 107ft
2004 Porsche 911 GT3------- 113ft
2007 Porsche 911 GT3 ------ 98ft
But I agree, all things help, ABS helps and wider, stickier tires help, but marginally. Bigger brakes work better at dissipating heat and Ceramics work better still.
some standard vs ceramic comparisons;
Ferrari 360 -------- 117ft
Ferrari 360 CS ---- 107ft
2004 Porsche 911 GT3------- 113ft
2007 Porsche 911 GT3 ------ 98ft
09-07-2012, 12:34 PM
#43
Former Vendor
Mark, I took the idea from your thread and mixed it with Steve's idea for 2 piece rotors and combined them. You do have to grind about .065" off the top and bottom of the caliper where the crossover tube bosses are if you use S-4 calipers because of the larger diameter rotor. You do not have to grind if using GTS calipers.They work great and the stopping is awesome. I street drove them but tracked them for 2 days at Watkins Glen and it certainly builds confidence knowing that when you hit 140 at the end of the back straight and hit the brakes before the bus stop, that you're going to make it.
09-07-2012, 04:02 PM
#44
Rennlist Member
Mark made the statement that tires matter more, and you re-posted a couple of claimed stopping distances - and didn't mention WHEN the tests were done, or WHAT TIRES were used, or even if ABS was employed.
Tire technology has changed in the 30 years between the 928S and the TeslaS.
ABS technology has changed (or been invented) in the same period.
Yes, brakes turn kinetic energy into heat - but it is the tires' grip on the road that drives the braking system.
You kind of acknowledged this with "No magic tires...", but I beg to differ.
If you compare what 2012 R spec tires can do, to what was possible with tires available for a street GT in 1985, "magic" seems ENTIRELY plausible.
Tire technology has changed in the 30 years between the 928S and the TeslaS.
ABS technology has changed (or been invented) in the same period.
Yes, brakes turn kinetic energy into heat - but it is the tires' grip on the road that drives the braking system.
You kind of acknowledged this with "No magic tires...", but I beg to differ.
If you compare what 2012 R spec tires can do, to what was possible with tires available for a street GT in 1985, "magic" seems ENTIRELY plausible.
09-07-2012, 04:06 PM
#45
Rennlist Member
Mark, I took the idea from your thread and mixed it with Steve's idea for 2 piece rotors and combined them. You do have to grind about .065" off the top and bottom of the caliper where the crossover tube bosses are if you use S-4 calipers because of the larger diameter rotor. You do not have to grind if using GTS calipers.They work great and the stopping is awesome. I street drove them but tracked them for 2 days at Watkins Glen and it certainly builds confidence knowing that when you hit 140 at the end of the back straight and hit the brakes before the bus stop, that you're going to make it.
what is that adapter set up. its hard to see. you have some axial bolts showing, yet the entire S4 attachement set up is radial. how did you do that magic. ill change next time i need rotors if that is possible for us mortals!