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Stopping a 2500 HP Street Car with LP Racing’s 13-inch, 6-Piston Brake System

October 2020 • By Nestor Cabrera
Presented by USAutomotive.co.uk

The line of what we call a street car is very blurred these days. With most classic cars being emissions exempt the sky and the engine bay is the limit on what you can stuff under the hood. A lot of car builders have been cutting off the front clip on their builds and installing a lighter, more roomy tube chassis that allows for an open canvas to build what the heart desires.

Andy Bond’s ‘Ugly Sister’ is a typical Drag Week car used here for illustration purposes only. It does not have an LP Racing strut assembly.

With advances in engine technology, EFI and super/turbo-charging a 2500+ hp set up for the street is a reality. One event that has become the benchmark for street-driven drag racecars is HOT ROD Drag Week. Drag Week is the competition where street-legal drag-race cars run quarter-mile time trials every day for five days, driving on public roads between four different drag strips for a road trip of 1,000-plus miles unassisted by support vehicles. It’s the ultimate test of a street/strip car where drivability is just as important as straight-line performance—if they can’t make it to the next track on time then they are out of the competition.

Typical LP Racing polished strut assembly with lightweight wave rotor and six-piston Wilwood caliper.

Many builders tend to focus their attention on acceleration and sometimes overlook the important aspect of stopping. In the case of street-legal drag cars, these race brake systems just aren’t up to the task.  When you have to drive hundreds of miles, loaded with all your gear, spares and tools, and having to use the brakes a lot more, a basic drag brake system might not cut it.

Typical existing front strut/brake assembly with simple disc, two-piston caliper on a 15-inch wheel.

If you are familiar with the brake system on drag cars, there isn’t much to them, usually a single-piston caliper mated to a small, solid rotor. The surface area and clamping force of the brake system is minimal as is the ability to dissipate heat. If you know how a brake system works, heat dissipation is a key stopping component. When a rotor heats up, the brake pads have a more difficult job slowing down the rotor, which in turn affects the stopping distance. If you have ever experienced an overheated brake system, you know it doesn’t matter how hard you push on the brakes, the car just doesn’t want to slow down.

Afinia industrial add-on for EinScan-Pro 2X and 2X Plus 3D scanner is used to scan the parts such as the spindle shown below the tripod.

The team at LPRacing.net used all the resources at their disposal to make a better mouse trap. They took the typical coil-over spindle mount system found in hundreds of racecars and scanned it to make a CAD drawing which allowed them to manipulate key components and create a digital mockup of the system they were trying to improve.

Once all the parts had been designed and mocked up in CAD, LP used one of their 3D rapid prototyping printers to create a composite part that could be used to test fit on the car before an expensive prototype was produced. This process allows for creating a better, more accurately fitting, cost effective part while reducing the R&D time.

Waylon Jeffrey sets up the CNC mill to carve out the parts.

Once the final design was achieved the information was sent to their CNC machine and a functional prototype was produced for final fit check and testing.  

The LP Racing system is designed to provide superior performance while maintaining minimum un-sprung rotating mass using forged aluminum hats and a lightweight 12.9-inch, full-floating steel rotor.

The LP Racing brake system is designed to work with either a StrangeEngineering.net or SanthuffShocks.com front runner tube chassis coilover shock/strut system. The system is designed to provide superior performance while maintaining minimum un-sprung rotating mass by using forged aluminum hats and a lightweight 12.9-inch, full-floating steel rotor. The larger rotor affords ample surface area for heat dissipation. Mounting the rotor dynamically allows controlled movement or flotation at the rotor mounting point, eliminating thermal-induced stress and subsequently rotor distortion, i.e. warpage.

The system is also available with a wave rotor that reduces un-sprung weight and rotational mass while giving the brake system an aggressive look.  You can order the system with either 2-piston or 6-piston Wilwood Dynapro calipers which deliver superior clamping force. The brake system is designed to be used with 17-inch or larger wheels, which are becoming more popular.

With the LP Racing Front Runner system you don’t have to worry about stopping anymore and can focus on making it to the finish line in one piece.

For more info contact LPRacing.net