The Results
As far as performance goes, this first round of modifications on my FRS really did wonders to up the level of overall grip and braking confidence on the street and at the track. Where it was easy to find the limits of the stock wheels and tires, the new bigger, grippier wheel and tire combo provides oodles of cornering grip without sacrificing a lick of the front to rear handling balance that makes the FRS so special. The suspension upgrades too only add to the overall performance of the car. The wide range of adjustability from those KW Clubsports really gives you a great working canvas to hone the handling of the FRS to perfection. Of course, the Brembo big brakes really finish off the whole package nicely, delivering that throw-an-anchor-out-the-window feeling when you stand on the pedal. So while all this added performance is worth the price of admission, the cherry on top is how much these mods really complete the look of this already great looking car. The timeless TE37 wheel design fills out the fenders to perfection, and then the bright red Brembo calipers and larger diameter rotors fill them up with a look that means business.
An overlay comparison of the GPS lap data before and after modifications reveals a considerable improvement in the on track performance of the FR-S. The bar across the very top of the graph shows corners (Red and Blue segments) and straights (green segments) and the first overlay at the top of the graph shows lateral Gs comparing the stock FR-S (dark blue line) against the modified FR-S (pink line) over one lap of the test track (Toronto Motorsports Park). It’s clear right away that the modified FR-S holds significantly higher g-forces while cornering, especially in the first half of the corner, as you can see that the cornering Gs build and peak quickly thanks to all the added grip. The high Gs aren’t being sustained all the way through every corner, but it’s likely possible to improve that with some more track time and setup changes. Below the corner Gs on the main part of this graph are the speeds of the stock and modified car. You can see right away that in the first corner, the modified FR-S (red line) is able to brake much later than the stock car (light blue line). This sheer stopping power from the upgraded tires and the big Brembo brakes gives an advantage that along with higher exit speeds from increased grip really adds up over the entire lap. Finally, the separate section along the bottom of this graph shows the time saved over the course of the lap, where a little extra grip adds up to a whole lot of time, almost 4-seconds to be precise. Keeping in mind that the modified car put down this lap in only a few sessions with very few setup changes, there’s likely even more improvement to be had simply by optimizing things like tire pressure, alignment and damper settings.
The traction circle graph (showing various points of lateral and longitudinal Gs over the course of a lap) is also a really interesting way to visualize the increased traction in all directions. The red plots of the modified FR-S show huge lateral gains (far left and right of the graph) and even bigger deceleration gains (bottom middle of the graph) compared to the stock data points (the blue plots). The outer points show that in every area of handling the traction circle is really being “filled out” more fully and expanded as well. It’s worth noting that the car’s ability to corner and decelerate at the same time, as depicted by those plots in the lower right and left quadrants, has also improved, meaning I was able to more effectively trail brake into corners to get the car rotating earlier, which then lets me transition back onto the gas earlier. As you can see from the summary data below, this translated into higher top speeds.
Stock FR-S | Modified FR-S | |
Lap Time | 1:27.882 | 1:23.925 |
Top Speed | 92.4 mph | 97.4 mph |
Peak Cornering G Force | 1.14 g | 1.23 g |
Peak Braking G Force | 0.79 g | 1.11 g |
The bottom line, for me at least, is that my FR-S with just a few bolt-on mods is now ripping significantly better than it did off the showroom floor and has the looks to boot. Almost a four second improvement over the initial lap time is a real testament to how well this chassis responds to modifications while retaining its fun to drive character. With some additional suspension tuning and a maybe a few extra wheel-horsepower, this FR-S has the potential to shave a few more seconds of an already impressive lap time, getting closer and closer to embarrassing cars that cost multiples of its sticker price. Speaking of which, yes I did pass that pesky 911 GT3 RS, once the driver realized he was holding me up in all the corner.
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Hello! Excellent write up and beautiful setup! I have a question about the wheels (because I am about to buy the exact same ones) Will they work with the stock suspension on my ’17 86? At least until I can get the KW v3 suspension I want. Next, are the wheels visibly concave? I can tell a bit from the pics but just want your reassurance, I love the look of concave and was wondering what the least amount of offset I could go would be. Anyway I don’t even know if you’ll see this or if I will get… Read more »
The TE37’s in this spec definitely have visible concave faces. Not super aggressively concave, but it’s there. These wheels or similar spec will work with the stock suspension. 18×9.5 +38 offset is about as aggressive as we’d go on stock fenders, any less offset than that and you’ll need to roll the fenders a bit. Thanks for reading!
I’m curious what other upgrades you’ve made to your track FR-S, as well as your experience dialing in the suspension settings.
I’m also wondering if there are any reliability/durability-related upgrades you’d recommend?
That was a nice write up. I’m just curious if you made all this modifications on the same time or you started with the wheels and tires with stock suspension. I want to know if your Te37SL And Tire size perfectly fit in the stock suspension.
And Additional question where did you buy your te37 sl with 35 offset. I kept on searching for that size but it seems it doesn’t exist or maybe they are selling that size anymore.
We put the wheels on after the car was lowered and modified but they should fit stock suspension.
Great article with good photos and graphs – all very helpful. I was sorry to see that you’re an atheist, though… “We went with their recommended ride height to ensure … … appealingly low from an atheistic point of view”. Oh wait, maybe he means “aesthetic”! 🙂
Hi !
Thank you for this great article ! If you don’t mind I have 2 question for you :
– even with a -2° camber, ET35 seems to be a pretty big offset, setting the external face of the rim out of the arches, especially in the rear. Did you have to roll the fenders ?
– At full lock, do you have even the slightest kind of rubbing in the front ?
Thank you very much !
Yes, we rolled the rear fenders slightly, just to be on the safe side. No rubbing front or rear with this setup.
you mention using 18×9.5 +35 but there doesnt seem to be an available te37 in 5×100 that matches that. did you convert to a different bolt pattern?