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Porsche 928: Brake Modifications

You can never have strong enough brakes. Read about some popular brake modifications below.

By Piyush Kayastha - March 23, 2015

This article applies to the Porsche 928 (1979-1995).

Porsches are known to come with a lot of go. When it comes to driving your performance sports car, the safety of you and your passengers is of the utmost importance. The Porsche 928 has been known to lack enough braking power. You can strengthen your braking system by replacing the calipers and pads with performance ones, replacing the rotors, or replacing the fuel lines. You can also purchase a full brake kit that comes with nothing but performance parts.

Brake Modifications

Calipers and Brake Pads

DIY Cost – Front and rear caliper set ($845) + motiv power bleeder ($45) + brake fluid ($30)

Professional Cost – 2-4 hours minus labor

Skill Level – Moderately difficult; Requires removal of brake components and successful bleeding of the brake system.

The upgrade to 4-piston calipers provides increased stopping power while doubling in weight savings for the track racer. A common problem this also addresses is the ability to fit a variety of wheels. With the larger 6-piston calipers, clearance is an issue. As a bonus, there are several types of pads available for 4-piston calipers. Forum members have shared the part numbers for related parts:

  • GTS Big Black Left Front Caliper - 928.351.423.03
  • GTS Big Black Right Front Caliper - 928.351.424.03
  • S4/GT/GTS Black Left Rear Caliper - 928.352.421.03
  • S4/GT/GTS Black Right Rear Caliper - 928.352.422.03
  • Hawk Front HPS Pad Set - HB184F.650
  • Hawk Rear HPS Pad Set - HB170F.650

Rotors

DIY Cost – Pair ($994) + motiv power bleeder ($45) + brake fluid ($30)

Professional Cost – 2-4 hours labor minus parts

Skill Level – Moderately difficult; Requires removal of brake components and successful bleeding of the brake system.

A popular upgrade. The rotors are light-weight and "floating," offering better braking. Due to the reduced "unsprung" weight, they double up in performance for Porsche 928s.

Brake Lines

DIY Cost – $130 + motiv power bleeder ($45) + brake fluid ($30)

Professional Cost – 1-2 hours minus labor

Skill Level – Moderate; Easier than removing rotors and calipers, but will require proper bleeding of brake system.

Many "kits" on the market today include stainless and braided brake lines in their upgrades. This is an improvement over stock because the original ones are made of rubber and are prone to being worn through by rubbing on hard turns and cornering, especially if you track your car. These can be replaced at the time the rotors and calipers get upgraded.

Pro Tip

While upgrades can be done in parts, it is highly recommended to perform this upgrade with all parts considered. This includes brake pads, rotors, calipers, brake lines, and also the possibility of changing spindles upfront to accommodate the larger calipers and rotors. The spindle conversion is specific to your VIN# and only applies to a set of Porsche 928s built during a specific year range. Related discussion links can provide more detailed information.

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