In my last year of Mechanical Engineering at the University of Utah I was able to participate in the Formula SAE program. The concept behind Formula SAE is that a fictional manufacturing company has contracted a student design team to develop a small Formula-style race car and then the prototype race car is to be evaluated for its potential as a production item. When deciding what team I wanted to be on I chose suspension because I knew the real trick to making a fast car is designing a great performing suspension and tuning it to perfection.
In the formula SAE program, the suspension is unrestricted except for safety regulations. Most teams opt for four-wheel independent suspension, almost universally double-wishbone. Active suspension is legal. Unfortunately most of us can’t design a one off suspension for our everyday cars but we have the ability to upgrade and tune our suspensions to achieve handling nirvana.
The Mazdaspeed3 is a great platform to tune on for power and handling, however it is a heavier front wheel drive (FWD) vehicle and some measures need to be taken to minimize understeering. If you are not familiar with understeering, it is when the car doesn’t want to turn as much as you are telling it too. Many of you may have experienced this in other FWD vehicles over the years and know that this tends to be a universal problem. Actually, most production cars are designed to understeer from the factory for safety reasons, but it is especially prevalent in FWD cars. With a few tricks you can make your car handle much better and minimize unwanted understeer.
The first step I would suggest to achieving a great performing suspension is upgrading the rear sway bar. The CorkSport Rear Sway Bar is adjustable to help you tune your car to your driving style. By installing a stiffer rear sway bar, the car will want to lose traction in the rear first instead of the front, reducing understeer. If you go stiff enough, the car will begin to oversteer in hard corners, so we recommend starting in the outer-most position with our Rear Sway Bar. If the car feels like it’s still understeering, move the end link to a stiffer setting. If you feel like the car is oversteering too easily, move the end link to a softer position.
For the next step, the CorkSport Front Sway Bar would be a good path. Anti-Sway Bars do more than just keep the car from rolling side-to-side when cornering; they help with the weight transfer of the vehicle during a turn. Normally most of the vehicle weight wants to transfer to the outside tires, but a stiffer sway bar helps weight transfer more evenly, which means the outside tires won’t lose traction as easily. The reduced roll of the vehicle can also help increase driver confidence by improving the cornering potential of the vehicle.
With stiffer sway bars, more of the suspension loads are being transferred into the chassis. To combat this, extra bracing is helpful to keep the chassis rigid. CorkSport produces a great 1-Piece Front Strut Tower Bar that helps transfer the loads from the struts onto the car more evenly between the strut towers. The CorkSport Rear Chassis Brace Set also reduces rear chassis flex by 15% which can help the stiffer sway bar in the rear by putting more force on the chassis. If you don’t want the full set you can also just get the Rear Chassis Brace that ties together the rear shock towers which will still help out greatly or you can get a CorkSport Chassis Brace to replace the stock chassis brace underneath the car which will increase the stiffness of the chassis between the front and rear suspensions.
Once you have gotten to this point your chassis is well braced and your sway bars have reduced the weight transfer during cornering, but there are still a couple more things you can do. CorkSport’s newly released Lowering Springs will lower your car’s center of gravity and increase the spring rate over your stock springs. This provides a stiffer ride that will increase the handling performance of your car while still being great for the street. Not only do they add to the handling of the car, but they will also improve the look by giving your car a more aggressive stance and decreasing the gap between your wheels and fenders. Be careful not to over-lower your vehicle. While it looks good, it can negatively affect the suspension geometry by throwing off the roll center of the vehicle. The CorkSport Lowering Springs decrease the ride of your vehicle to achieve a great look while maintaining the geometry of the suspension.
After springs, upgrading the dampers would be the next suspension improvement I would recommend. CorkSport sells Koni Sport (Yellows) for the Mazdaspeed3. Koni is world renowned for their great Sport series shocks. These will replace your factory front struts and rear shocks and give you adjustable rebound to help dial in your Mazda’s ride.
In this post I have laid out a great path to making your Speed3 handle even more brilliantly than it already does, but remember, for those of you who autocross, check your rule book to see if any of these upgrades will force you to change to a faster class.
If you have any questions about these products please feel free to gives us a call or shoot us an email, we are more than happy to talk to you. Thank you for supporting CorkSport.