We’re very excited to announce that Project #RallyFist, our 2015 Ford Fiesta ST project car, will be riding on Falken RT615K tires in 215/40/R17. Perfect upgrade for the FiST in stock diameter.
In our quest for a sticky performance tire upgrade, and after a lot of research, our Fiesta ST is officially riding on RT615K tires. The Falken RT615K tire is an upgrade over the previous model RT615. While the original RT615 was hugely popular in auto x, dominating in SCCA Solo 2 events, it was also a widely used track tire – just not as popular on the track as it was in autocross. The new rubber compound in the RT-615K bridges the gap between autocross and track with a compound that is much improved for the higher temperatures typically found during track use.
The Falken Tire Azenis RT615K is pretty much a street-legal track tire. They are as close to a slick as a DOT-Approved tire can get. The Azenis RT615K is very popular around here and a perfect choice for top performance in Southern California. Why? Since it is such a high-performance summer tire, it’s better for places with little snow or rain… two things we rarely get in SoCal. See where we’re going with this?
Since our Ford Fiesta ST will not be seeing much rain and likely zero snow, this is the perfect no-compromise tire for our project car. In other areas where there is a lot more rain, the Falken Azenis RT615K is still very popular for dedicated track or autocross use. It’s simply a matter of having an extra set of wheels to swap out in order to use these only for track days or auto x events. Additionally, we don’t have to tell you how good these are for drifting, since you all know how popular Falken is in the drift scene. The combination of massive grip with smooth slip seems to be the ticket.
Even though we don’t get a whole lot of rain here, we’re still keeping the stock wheels for the rare occasion with dumping winter rain. Just in case. That said, we’re very excited for the upgraded rubber. With the Fiesta ST COBB Tuning Stage 3 upgrades in our car, we need stickier tires in order to effectively put that power to the ground. The upgraded FiST will also benefit from the extra grip on the twisty canyon roads.
For reference, the stock Ford Fiesta ST tire size is 205/40/R17. To get that extra bit of traction and contact patch, we’ve decided to run with 215/40/R17. This is still a very compatible tire size that won’t throw the speedometer off by more than a tiny percentage. Some people are running slightly wider tires, at 225. While other are running slightly taller ones with numbers like 215/45 or 205/45, but we felt that might just be a bit too tall – even though most claim to have success with them. The Fiesta ST has such good dynamics, we didn’t want to throw that off with tire dimensions much too different from stock. We just wanted more stick, more performance and better looks. By the way, the large wheel lip protector, flange shields, wheels scuff guards, rim guards, rim protector (whatever you call them) integrated into the tire is a nice feature and it looks really good too.
For more details about the Falken Azenis RT-615K tire, check out the official page here: Falken Azenis RT615K