One common thing I hear from customers is “What should I do with my car?” My reply normally is “What are you going to do with your car? What are you plans and what do you want it to do?” Having some idea of the end plan for your car can really help you out when deciding what to purchase. Let’s take a look at the suspension first.
Suspension is something which there is wide range of options available for most Mazdas. One of the questions I ask customers “Are you just going to drive this on the street, or will you also take it to the track?” This really gives me a good idea of what to suggest for modifications. The difference between the street and track suspension normally comes down to how stiff the suspension is. Most track suspensions do not work very well on the street because the bumps in the road cause the car to ride really rough, because of the higher spring and dampening rates of the shocks and springs. A good street suspension will have a stiffer ride compared to stock but still be reasonably comfortable when driving on public roads.
A good track/race suspension will set you back $1500+ depending the on the shocks/springs or coilover options. A good street suspension will run about $1000 or less for springs and shocks. The advantage of coilover suspension is the ability to change ride height, shock dampening and spring rates. The ride height adjustment is good for lowering the center of gravity on your car. Being able to change the shock dampening allows you to fine tune the ride of your car. The ability to change the spring rate allows you to make larger changes to how the car performs under cornering. Street strut and spring suspensions are comprised of a lowering spring which matches the original dimensions of the stock spring but with a different compression rate. Most springs sold lower Mazdas from 1-1.5 inches. Upgraded struts also fit the original dimensions but have different valving to change the rebound and compression. This makes the strut either move slower or faster than stock depending on the application. There are street coilover suspensions available as well from some manufactures like AutoExe.
AutoExe 2010+ Mazda 3 Street Coilovers shown above.
Upgraded suspension arm bushings can give you better feedback with less deflection or give but the trade off is a more vibration into your Mazda due to the increased stiffness. A commonly upgraded bushing is the front control arms. The advantage of the front control arm bushings is less deflection in the bushings making the steering response faster since the bushings have less give. The upgrade bushings also help in launching the car from a standstill by decreasing or eliminating wheel hop. I recommend looking at our tech article on urethane bushings to get more information.
Sway bars are another option to upgrade in your suspension. The sway bar keeps your car body flatter under cornering but it can also affect the balance of the car. Installation of a larger rear sway bar can create over steer which to simplify things make the back of the car slide first under hard cornering. This is great for autocross and rally cross where you need very tight rotation of your vehicle to get around cones. On a street car this can be handy but it can also catch you out if you are not experienced enough to know how to counter the change in surprise situations. The last thing you want to do is call a tow truck to pull you out of a ditch when the back end of your car becomes the front end when it slides out.
H&R Swaybars above
The last item to bring up is suspension bracing. What the braces do is supplement the vehicle chassis to make it stiffer. You really start to notice the improvements for braces on uneven surface roads or under hard cornering. In open top cars like the Miata/Mx-5 and open trunk hatchbacks like the Protege 5/Mazda 3 the addition of the braces can be noticed in day to day driving due to the additional stiffness in the chassis Check out our tech article on strut tower braces for more specific details.
CorkSport Rx8 Aluminum Brace with and without the engine cover above
For most street driven cars I recommend a good set of lowering springs and upgraded shocks/struts and move forward from there with braces and swaybars. If you have any questions on suspension feel free to email me at Derrick@corksport.com or give me a call and I can give you specific information for your model of Mazda.
I will cover engine modifications and brake upgrades in future blog posts.