Project Infiniti G20 Racecar: Making it Stick With APR’s Wing and Splitter
Project G20 is an aerodynamic disaster. Blockish shape, steep windshield and rear glass, and open bumpers all lead to a car that makes masonry look sleek. As a result of poor aero combined with suspension balance set up in line with Grandma Paule’s saying of “loose is fast, don’t be a
minor tremendous ridiculous handful at anything above 75mph. Four wheel drifts on the oval at Auto Club Speedway, while entertaining, aren’t a good long-term survivability plan. When Kojima spun our car in turn one his first lap out, we knew it was time to tame Project G20’s inner bucking bronco with some aero bits from APR.
Indeed, the competition probably appreciates G20’s aerodynamic efforts. After a particularly heated battle with Justin Taylor in the Rockstar Garage S2000, who was running about 1-2 seconds a lap quicker than Project G20 at the time, I asked him why he didn’t push for a pass sooner. His response: “honestly, I was just waiting for you to crash, but it never happened.” Huh.
Downforce is one of those vacuous (see what I did there?) terms that gets thrown around too much. Some refer to downforce directly created by wings, canards, splitters, and other accoutrements, while others refer to the net effect on the vehicle from various aerodynamic aids as well as demerits. For the sake of sanity, and this article, we were primarily after making the car less floaty and dangerous at speed, so actual measurement values didn’t matter to us much (which is nice, seeing as MotoIQ hasn’t bought a wind tunnel yet). We’ll just trend this article towards measurable data from manufacturer’s spreadsheets and lap times, as well as subjective results on the car’s behavior. While selecting our aero mods, we needed to be mindful of creating too much aerodynamic wake with our vehicle, as its brickish shape already makes for easy passes on long straights by drafting competitors. Lastly, let’s be honest: Project G20 does not look like a racecar. At all. Our guess is more people looked at our car on the trailer and wondered why we put stickers all over Mom’s car than thought “hey, look at that racecar!” Now they’ll look at it and wonder if mom gets angry driving a car with stickers and wings on it. Sort of a win?
To begin our aerodynamic aids, we needed to look at the major problem areas that need addressing. First and foremost on the list was the plastic rectangular parachute known as the rear bumper. Since the P10 chassis was designed in the late 80s, Nissan didn’t bother to do anything with the airflow exiting the ass end of the vehicle because (1) gas was a whopping buck a gallon, and (2) the government wasn’t breathing down manufacturer’s necks quite as badly so 30mpg highway was good enough. As a result, the rear bumper is a giant scoop perfect for catching wayward air and lots and lots of dead leaves. Add in the giant hole left behind by the ectomied muffler, and we’ve got the previously described parachute. This no doubt contributed quite a bit to the vehicle’s overall drag number, it also probably made a shit-ton of lift. Terrible.