RoadsterSport High Performance Springs 2016-2024 FRONT RATE 300 LBS, REAR 200 LBS FOR ND MIATA AND FIAT 124

Serious performance springs for the serious street enthusiast, ENOUGH RATE for Canyons to Autocross to Track! We took a Top Time of Day with these on Koni Sport shocks at autocross event with 100+ competitors.

Tested on our ND Miata and Fiat 124 (shown here on our own Fiat 124 and a customer ND, both built on same ND chassis in Japan, same lowering effect). Stock heights were 14.25 to 14.75 (measured center of wheel up to fender lip). Lowered heights with these springs approximately 13.75 on stock shocks, settles as low as 13.25 as shown here on KONI Sport shocks which are lower pressure than stock shocks. Important to understand these are really too much rate for base trim stock shocks, the stock Bilsteins on the CLUB version handle these well, ideally used with the Koni adjustable SPORT shocks or Bilsteins with our short bump stops. Your results will vary depending on which shock you use and the age of the shocks, as shock pressure declines over time the car will settle lower.

Numbers here are for SOFT TOP version of MX5, these are not compatible with the RF chassis. With the additional weight of the RF the heights are incorrect.

These Miata springs feature increased spring rates for vastly upgraded handling capabilities. Certified high-tensile SAE spring wire materials. These Miata springs are cold-wound on modern CNC coiling machines, then stress relieved, pre-set, and shot-peened for maximum durability.

Rates 300 lb/ft Front, 200 lb/ft rear.
Roughly DOUBLE STOCK spring rates, which are 156 front all models, 80 rear for most models (Club model gets 100 rear). -All spring kits are powdercoated.
-Drop amount varies depending on shocks used.

BRIAN'S APPLICATION NOTES: My new favorite simple formula for around town fun that can hit the canyons or autocross/track the weekends! Enough rate to make the car MUCH more flat in the turns without making the car harsh riding. Started this project with the idea of making the perfect springs to match with KONI Sport shocks, though they also work well with factory ND1 and ND2 Bilstein shocks in CLUB editions (too much rate for the black body NON-Bilstein stock shocks). These are a great choice for those who want to replace the soggy factory springs to take out much of the crazy factory body roll. Improves handling massively without dropping the car too much, just half inch of lowering on bilsteins, total 1 inch of drop if you also add our KONI SPORT shocks. Lean on them in the turns and you will find the car is MUCH flatter and faster because the tires stay flatter to the ground instead of rolling onto the sidewalls as happens with the soggy factory springs. For those who want MORE THAN HALF INCH DROP than these springs provide on the Bilstein shocks, combine these springs with our KONI SPORT shocks which are lower pressure to total about an inch of drop.

INSTALL NOTES: Important not lock down the bolts to the suspension after install while the car is suspended in the air with the suspension fully extended. Bounce it on the ground, then give it a drive around the block with the bolts just snug so you get it to settle before you torque everything ON THE GROUND. Many shops will NOT know to do this...SMART CUSTOMERS PRINT ALL THIS PAGE FOR THE INSTALLER! See details in our forum installation section from NC application, thread is titled: "Spring Installation, Mazda Workshop Manual Notes" and factory TSB notes below. Once you do it right, drive it 500 miles and then do it again (which usually results in another quarter inch or more of lowering)....and then do the alignment. ROCKY'S TIPS: Our head mechanic Rocky has his own method that seems to work even better than the factory TSB. Once he finishes install at each corner he jacks up just that corner with BOTH UPPER AND LOWER LINKs loose, so the full weight of the car is compressing just that corner, then he torques the bolts...and he finds car will still settle with 500 miles but usually only another 1/8th inch.

UNBOXING NOTES:
These springs are manufactured to our specifications by Progress, the same makers as our standard Progress springs and RF springs, so don't be alarmed when a box of springs that say Progress arrives. Verify the part number on the box is correct for RoadsterSport springs: 40.1135.