A Honda Fit For Street and Track

Evidence of gradual movement toward a goal produces the sort of pleasure that justifies long hours and many frustrations. I am pleased to say that, in recent months, a short list of modifications has helped revive the project on my 2009 Honda Fit that began last year.

The salient finding from the last installment in this build series was that in long, constant-radius corners, the Honda Fit lacked the front-end bite needed to feel fast. I found the car less willing to rotate into the corner when coming off the brakes, and though I could occasionally force it into a slide and usually trusted its direct steering, the body movements weren’t well controlled. Running over bumps resulted in lots of unnecessary body movement. Generally speaking, the little Fit was fun and surprisingly capable, but far from sharp.

What I wondered about was whether it would be fun if I could make it a bit more lively in my hands. With some minor work, maybe I could spar with earlier Miatas and the like. Forget setting mega lap times. I was more interested in the simple pleasures of driving and saving money.

New Balance

As mentioned earlier, the core criticism I had of the car in its earlier state of tune was its tendency to understeer. I was hoping for a freer car, given the need to straighten it sooner than some rear-drive cars with similar specs. It simply didn’t rotate as willingly as it needed to.

I began by considering which spring rates, or what spring ratio front to rear, would make the desired effect without destroying ride quality. The Silver’s Suspension Neomax coilovers that the car came with were geared toward street driving with modest 6 kg and 3 kg rates, front and rear, respectively.

By increasing the rate more at the rear, I might induce more rotation at entry. A similar track-street Honda Fit built by Honed Developments uses 6 kg/mm springs at the front and 8 kg/mm springs at the rear with a different coilover. They do not, however, run as thick a rear sway bar as I do, a Progress 21mm item. Effectively, a bar that thick increases the rear spring rate slightly.

Honed Developments determined that these rates will suit the suspension frequency. Using 6 kg/mm up front results in ~2 Hz suspension frequency, and 8 kg/mm springs in the rear results in ~2.7 Hz frequency. These frequencies have been shown to work well with many wingless front-drive Hondas with tires in typical sizes.

Running a slightly higher frequency in the rear relative to the front is due to the limitations of the rear suspension design. Because the rear axle does not allow for camber or toe adjustment, the idea, essentially, is to force the car to rotate relatively early in the corner, thereby straightening the car to limit the work the front axle needs to do, and improving acceleration.

I decided to make the cost-effective decision and picked Silver’s Suspension for a new set of Neomaxes with 8 kg/mm springs at all four corners, which was slightly higher than I had planned, but Silver’s insisted. My worries about ride quality were squashed shortly after WORKS Motorsports in Sonoma, Calif., installed the coilovers in a hurry and had me back on the road, even after having to torch a bushing that had rusted in place. The quick turnaround and welcoming customer service made it a shop to keep at the front of my mind for when I need a true professional. I’m no pro when it comes to wrenching.

The notable changes were higher midcorner speeds, an urgency at the front end, aided in large part by the new BLOX S2000 rigid steering rack bushings. Made for a different Honda model, these drop in with the aid of a press, and the effect is noticeable. The Fit’s steering is fine from factory, but the off-center feel and detail leave something to be desired. With these bushings in place, the wheel felt sharper and more informative than before. For the cost of an inexpensive part and a somewhat challenging installation, the car felt far more alive.

The suspension improved control over bumps, with nothing other than mild oscillations at the rear at freeway speeds to bother me. That control made it more capable over backroads at the cost of a minor increase in firmness, which was a worthwhile tradeoff. By that point, I had no illusions about finding any real comfort with a stiff torsion beam rear, and I realized that some harshness was expected, though not unbearable.

Fast Footwork

So, whatever benefit the new suspension brought on track day could be seen as a plus. In preparation for an insightful track day, I swapped out old Falken RT660s for a set of Nankang CR-S tires provided by Elite Performance in Burlingame, Calif. The Nankangs’ road noise was minimal, comparable to the Falkens, and knowing nothing about what pressures these tires liked, I set them with the same 31-35 split, front to rear, respectively.

Balance was the main item on the agenda, but if there was a way to get a few extra horsepower for cheap, then why not? Injen Technology supplied its SP Cold Air Intake System, which promised another 8 horsepower and 7 pound-feet of torque. Not headline-generating numbers, but a noticeable gain for a lightweight car with an anemic powerplant. To my surprise, I found this intake system offered more than a modest bump in power.

What caught my attention at first was a slightly throatier note around 4,000 rpm and more midrange shove, and as I revved the motor out, the VTEC crossover was, for the first time, audible, and accompanied with a little extra push. Prior to that, that change above 5,500 rpm was barely discernible.

Test Time

On a sweltering day at Thunderhill east, all I needed was half a warmup lap before I felt comfortable in the car.

From the outset, the front end was sharp and eager to turn in, with a crispness to the steering that made it easy to place the car precisely. Braking reasonably late and minimally and briefly, chiefly to help set the nose into Turn 2, it stuck to the desired line on a moderate amount of maintenance throttle.

This grip and poise gave me confidence in Turn 2, a long, constant-radius left that would challenge a front-driven car. It was satisfying to finally feel the car come alive and stick, and be at home on-track. Before this day, to be perfectly honest, I wondered if it would ever truly feel like a track car and not a modified econobox.

Minimum speeds were roughly 7 mph faster than the last time I visited Thunderhill, then running the Falkens and the old shocks. At corner exit, it was a cinch to pick the right time to apply the throttle and use the exit curbing consistently, and never did I have to lift due to a premature throttle application, something that happened several times in the past.

I have to attribute this greater accuracy in throttle response to the Injen intake. With the factory airbox, there was a latency that I had to get accustomed to. With the Injen in place, the relationship between my foot and the engine was more intuitive.

The first outings on track pre-Injen intake were filled with limiter hits since I couldn’t tell where I was in the rev range without peering down at the tach. After installing the intake, I could feel a notable bark in the cabin when was nearing redline, and so I could shift smoothly without losing any momentum, which is vital with a gutless 1.5-liter motor.

Additionally, throttle response had been sharpened with this intake system, and having the ability to bring the motor back up to a boil a few tenths faster contributed to a sense of increased speed and heightened engagement.

Probably due to the grip of the new tires, it would not slide as much at the rear as when I’d last driven Thunderhill on the worn Falkens. Instead, the rear stuck just about everywhere and the slightest amount of trail-braking was enough to set the nose in the tighter Turns 11 and 14. The understeer was all but gone, though it was hard to unstick the rear, even as temperatures climbed into the triple-digits. With these four mods, the car had gone from feeling a little lethargic to eager, responsive, and confidence-inspiring.

So much of that was due to the consistency of the tires, which considering the temperature, was remarkable. They were strong from the out lap and remained strong throughout the entire session, with only a barely discernible drop-off toward the end. With their stamina supporting me, I could whittle away at my approach to corners I hadn’t driven in years.

This is the first time I have felt like the car was meant for track work. Before these simple modifications, I had been unsure of whether the Fit was capable of leaving a lasting smile on my face. It had always had a quirky charm to it, and it was surprisingly surefooted on track for a city car, but until today, it never quite felt like an athlete. Now, with four important changes, it could run comfortably with prepped Miatas.

Satisfied for More

It’s still slightly lazy in fast transitions and comically slow on the straights, but it is undeniably sharper, more certain in its movements, and I feel more a part of the experience. BLOX’s bushings and Injen’s intake, two basic modifications with surprisingly noticeable impacts, have helped direct the course of this build series. If there’s a surefire way to get everything out of the car repeatedly, it is by clarifying the interface between car and driver. Even if its on-paper stats remain the same, being able to trim the car’s balance with the tiniest of steering and throttle inputs have made the experience that much more rewarding.

Satisfied with the major improvements made, I packed up, turned on Apple Carplay, drove home in complete comfort with a clean buzz and a clear mind. For better or worse, that buzz made me a little less concerned with unsheathing the credit card.

Once I got home, I ordered a couple items to improve that man-machine connection, and a couple more to help get everything out of the current suspension setup. Even after the buzz has worn off, that still seems like money well spent.