Mercedes Benz 2004 S430


StopTech Rear 332x32 ST-40 Big Brake Kit

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StopTech Rear 332x32 ST-40 Big Brake Kit StopTech Rear 332x32 ST-40 Big Brake Kit

Product Information

StopTech Big Brake Kits improve aesthetics and exceed stock brake performance in three areas. First, larger rotors increase heat capacity. Second, improved brake cooling dissipates absorbed heat. Third, stiffer calipers and stainless steel lines reduce system compliance.

The key, however, is to increase heat capacity and reduce compliance without upsetting the stock front to rear brake torque ratio, also referred to as brake bias. Regardless of rotor diameter, brake pedal ratio, brake pad material, or number of pistons in your calipers, your maximum deceleration is limited every time by the tire to road interface. If the brake upgrade you select adds too much rear brake torque (as many do), it will drastically shift the brake bias too far forward and reduce your car's ability to utilize the maximum traction of the tires at all four corners (even on ABS equipped cars), increasing stopping distances dramatically. In addition, too many pistons or pistons that are too large will make the brake pedal much more difficult to modulate, which limits a driver's control of brake input.


Advantages of StopTech Big Brake Kits over other brake upgrades:

  • StopTech Balanced Brake Upgrades™ with optimum brake bias offer the shortest stopping distance with the best pedal feel
  • StopTech offers the stiffest aftermarket calipers available, their patented bridge results in better clamping under hard braking and less pad taper
  • StopTech's patented AeroRotors® offer the best airflow available which results in better cooling, less fade and longer rotor and pad life
  • StopTech Stainless Steel Brake Lines are resistant to expansion which offers better brake modulation and a firmer brake pedal
  • StopTech Brake pads combine the benefits of premium street brake pads with aggressive friction formulas suitable for track day and autocross use.


StopTech ST-40 - 4 Piston Calipers

StopTech's ST-40 calipers are manufactured from fully forged aluminum for optimal strength and light weight. Forging also produces a beautifully finished, nonporous caliper. StopTech does all finish machining (such as piston bores sized correctly for the application), assembly and test in California. Calipers that are cast without being squeeze forged can have major issues with porosity which can even cause calipers to leak. Dust boots are standard on StopTech calipers to keep the pistons clear of contamination and extend the service life of the calipers. Competitors calipers designed without dust boots require rebuilding every two years.


 Advantages of StopTech's ST-40 - 4 Piston Caliper:

  • Pistons sized to match brake kit to vehicle application
  • 100% leak down and pressure tested to 2,500 PSI
  • Differential piston sizes minimize pad taper
  • Uses standard FMSI D372 brake pad
  • Weight: 7.94 lb (3.6 kg) unloaded
  • Silicone dust boots are standard
  • Made of forged aluminum alloy


StopTech's Patented Caliper Bridge

Using finite element analysis (FEA) modeling software, StopTech has designed a bolt-in bridge strong enough to stop distortion without sacrificing cooling through the top of the caliper. The squeeze forged StopTech ST-40 caliper has the least flex of any tested aftermarket or OE caliper. The air channel in the bridge helps air flow through the retainer, resulting in better cooling.


 Advantages of Stiffer Calipers:

  • Better performance with no vibration or noise
  • No radial pad taper
  • Better pedal feel


StopTech Stainless Steel Brake Lines

StopTech makes their own stainless steel brake lines in California from the highest quality parts available. StopTech brake lines consist of a Teflon® inner line that is covered with a layer of stainless steel woven braid. The Teflon® tube is very resistant to expansion under pressure and will not degrade from exposure to brake fluid. The stainless steel braid provides support for the Teflon and the weave is extremely durable against incidental impact and abrasion. Lines feature a clear abrasion-resistant cover for maximum protection against chaffing and particle intrusion. Every fully assembled StopTech Stainless Steel Brake Line is tested to a pressure of 4,500 PSI. StopTech is a DOT (U.S. Department of Transportation) registered supplier of brake lines.


Advantages of StopTech Stainless Steel Brake Lines:

  • StopTech Stainless Steel Brake Lines comply with TUV and FMVSS 106 safety standards
  • StopTech is a registered brake line manufacturer with the United States DOT
  • Shorter stopping distance through shortened reaction time
  • Strain relief devices to reinforce end fittings
  • Improved pedal feel and modulation
  • Tested to 4,500 PSI


StopTech Street Performance Brake Pads

StopTech ST-40 Big Brake Kits include StopTech Street Performance brake pads which are suitable for both street and light track use. StopTech Street Performance Brake Pads feature low dust, high initial response for cold stops, quiet operation, even pad wear and consistent pedal feel and performance. For more aggressive track use or race use, it is very important to select pads appropriate to the type of driving.


 Advantages of StopTech Brake Pads:

  • Wide operating temperature range improves stopping power hot or cold
  • Consistent and predictable performance
  • Excellent pad life
  • Longer rotor life
  • Reduced dust
  • Low noise

Slotted rotors are preferred over drilled due to their larger pad contact area and their resistance to cracking.
Zinc coated rotors are available for an additional cost. Zinc coating helps reduce surface rust on unswept portions of the rotor.


Brand: StopTech
Product Code: 83.563.0046

Product Options:


* Caliper-Rotor:

$5,193.50 $4,674.15
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