Project Crusher- Part 1

by Olaaf

Introduction to Project Crusher

Hello dear readers.. Most you who know us are probably familiar with AJ’s '98 Mustang that he races in NASA:

1998 American Iron Mustang | RHR Performance

Over the past few years he earned the sobriquet “Mr. Aero” in his endless pursuit of downforce. There isn’t much more to do on this car aerodynamics-wise. So a few months ago we purchased a V6 2015 mustang from a hurricane Harvey auction as well as the 3D model of the car. As we hinted at the time; we have big plans for it and now we’d like to share that plan and keep you up to date on our progress.

Project Crusher | RHR Performance

The precursor to Project Crusher was the development of some new wings, specifically a dual element wing legal for American Iron, and an Unlimited version designed for Super Touring & Time Attack.

Those wings have been designed and developed with CFD run on both the S550 and C6 Chassis, and the master plugs have been ordered and are due to arrive any day now.

Full Race Wings | RHR Performance

With our Aerodynamics consultant JKF Aero, we’ve set out to develop two aero packages for the S550. One package will be optimized for NASA’s American Iron racing class, and the other for Super Touring/Time Attack.

We are pushing the boundaries for American Iron rules; we’ve reached out to the national director for a clarification on a rule, and that certainly set off a storm! After the regional AI directors conferred, we received our (positive) answer. The question was related to 3d (airfoil) profiles being legal in splitters and canards, which they are- we are not running afoul of the “no front wings” rule.

In any case, these won’t be one-off aero packages but will be available to anyone who wants to buy them. Our objective is to create the definitive aero package for the S550, fully backed by data. No guessing. Another objective, and illustrated by our design choices on our new wings, is that the packages be upgradable- some components are reusable (or in the case of the wing for example, an upgrade kit will be available).

Still very much a work in progress, but here is a sneak peak of the packages. Please bear in mind not all components have been designed, and the components that are designed are still undergoing iteration and analysis.

Crusher in American Iron trim

Project Crusher AI Aero | RHR Performance

Crusher in Unlimited trim

Project Crusher Unlimited Aero | RHR Performance

Crusher diffusor (common to both trims)

Project Crusher S550 Diffusor | RHR Performance

Things are looking good at this point. In engaging our consultant, we’ve taken the extra step of designing for variable ride height and pitch sensitivity— not just straight-line analysis. 

We all know that mustangs tend to run relatively soft spring setups, so we wanted to be careful about taking vehicle dynamics into consideration. In fact, the initial splitter design for the AI package made a great amount of downforce (a Cl of about .65, but iterating to get this up to about .8) but during large forward pitch conditions, the Cl drops dramatically, so this is an area we are investing quite a bit of time.

Any comments or questions, please feel free to ask away. Best way to do that is contacting us, or posting on Facebook.