928 S4 vs Big Red brake calipers
#1
Nordschleife Master
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Join Date: Oct 2001
Location: Mount Pleasant, South Carolina
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Did a search with no results.
What's the difference between the two?
I know the Big Reds have more pad area, but how much?
Number and size of pistons?
Rotors diferences? Diameter and width?
Is it an upgrade from stock 930 brakes to 928 S4's? How much?
TIA
Jim
What's the difference between the two?
I know the Big Reds have more pad area, but how much?
Number and size of pistons?
Rotors diferences? Diameter and width?
Is it an upgrade from stock 930 brakes to 928 S4's? How much?
TIA
Jim
#3
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Check out the page Kahuna suggested
Here is some additional visual info
The caliper on the right is a 993TT Big Red, on the left is a 993TT rear, center is a 993TT rear modified for use on the rear of a 911. The 993TT rear calipers are the same size and use the same pads as the 993/928S4 front calipers.
If the stock 930 rotors are retained w/ 993/928 S4 calipers there is a minor improvement due to the larger pad area which spreads the heat out ~20%more than a stock 930.
If the Big Red is used then there is a large increase in available brake torque due to the much larger 322mm rotor which are needed w/ them, there is also an additional ~34% greater pad area to smear the heat around even more(~60% more pad than in a 930)
Don't forget that if you do one end of the car the other will also need attention.
Here is some additional visual info
![](http://forums.rennlist.com/upload/renntechbr029_small.jpg)
The caliper on the right is a 993TT Big Red, on the left is a 993TT rear, center is a 993TT rear modified for use on the rear of a 911. The 993TT rear calipers are the same size and use the same pads as the 993/928S4 front calipers.
Is it an upgrade from stock 930 brakes to 928 S4's?
If the Big Red is used then there is a large increase in available brake torque due to the much larger 322mm rotor which are needed w/ them, there is also an additional ~34% greater pad area to smear the heat around even more(~60% more pad than in a 930)
Don't forget that if you do one end of the car the other will also need attention.
#4
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Another visual
From l tp r 993tt Big Red front pad w/ 36/44 pistons, 993RS(993tt r 993 f have the same size pad) w/30/36 pistons, 965 r(930 f/r, 964 f/r are the same size) w/ 30/34 pistons
![](http://forums.rennlist.com/upload/racetechbr011_small.jpg)
From l tp r 993tt Big Red front pad w/ 36/44 pistons, 993RS(993tt r 993 f have the same size pad) w/30/36 pistons, 965 r(930 f/r, 964 f/r are the same size) w/ 30/34 pistons
#7
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Can I replace the front factory calipers of the 930 with the 993tt with no other mod
or I have to replace the discs with hubs too?