Speed Academy Discovers Benefits of Big Wheels on the Track

By -

Adding grip makes sense on a FWD Civic, and this badass video shows exactly why. 

So you’re tying your track car project together, and you’re faced with a choice: What kind of wheels do you use? Do you opt for roughly factory-size wheels to keep weight down, or do you go with something bigger and wider to put all that hard-earned power down? That’s what this video tries to uncover. “Everyone enjoys a little wheel and tire science. And today, we’re going to be doing just that,” says Dave Pratte, host of the Canadian YouTube show Speed Academy. To boil it down, Dave wants to find out: “is it worth making the trade-off between lightness and a shorter tire, which is better for gearing or acceleration, versus a heavier wheel and tire package that has a wider contact patch.”

The guinea pig car here is a sweet K-swapped 99’1 EK Civic Si. This cool coupe is road legal, but it benefits from a track-focused build, which will work to its advantage today. The wheels in question are 15″ x 7.5″ Konig Hypergrams with 225/205 Nankang AR-1 tires versus 17″ x 8″ Konig Dekagrams with 235/215 Nankang AR-1 tires. The lighter wheels weigh just over 34 pounds each. The bigger ones weigh just over 40.

Where the Rubber Meets the Road

Speed Academy's 15-inch versus 17-inch wheel challenge.

So Dave sets out at Toronto Motorsports Park to see which is better. Instantly, he may have spotted an issue with the smaller wheels.”I find if I go down to second gear,” he says, “I’m just banging the rev limiter as soon as I come out of corners, so I’m leaving it in third gear in a lot of the slow corners, and just having to get on the gas sooner and letting the revs build.” Something like this could prove to be a costly mistake in competition. But, best lap time on the three-kilometer course with the small wheels is a 1.22.5, which Dave says is about as fast as this Si has ever gone. So do the wider 17-inch wheels make a difference?

Immediately, it does. He can use second gear to its fullest. What’s more, it’s grippier and has a much better feel. “Front grip feels really good on these 235s. There’s definitely something to be said for a wider front contact patch on a front-wheel drive car.” He also can keep it in fourth gear in the straightaways, eliminating the need for a five-to-three downshift.

Speed Academy's 15-inch versus 17-inch wheel challenge.

“Wider was definitely better on our EK Civic,” Dave says. He raves about the added grip. Plus, the benefits of responsive steering, less push coming out of corners, and better gearing.  It all paid off too, with the Honda running a 1.22.0 on 17’s.

After this, Dave interviews Time Attack driver Chris Boersma, who swears by 17’s on his EK track car. We also get a good look at what Chris did to make his Civic such a monster. Then we get Dave’s final words, which serve as seriously good advice for anyone working on a track day build. He likes the look of the 15’s, and he likes their feel on the street. But he can’t deny the benefits of the ’17s. “The stopwatch doesn’t lie,” he says, “and I like to go fast.” If you’re looking to optimize your Civic on the track, it isn’t a bad idea to take his advice and think big.

Join the Honda-Tech forums now!

Comments ()