Project G20: Making it Stick With APR’s Wing and Splitter


The next two problem areas are at opposite ends of the vehicle. First is the front bumper area. Project G20 is turbocharged and uses an SR20, which means that it’s a sneeze away from overheating at all times. We’ve put a lot of effort into making sure that it doesn’t overheat, but we did it by going overkill and paid zero attention to airflow management until now. The predictable result is that airflow over and through the front end is completely stupid. Probably the biggest problem is that we don’t have anything cleanly separating airflow both before and after the heat exchangers in the nose, resulting in piss poor air movement through the radiator, oil cooler and intercooler. Bad.


Before this installment, this is exactly how the underside of Project G20 looked. Easy to work on, yes. Easy for air to exit the various heat-exchangers up front, no.

The ass end of the car is a bit of a mess too. To maximize headroom for rear passengers and accommodate the rear doors, Nissan made the rear glass way too steep to keep airflow attached. As a result, anything we put back there needs to be way above the decklid to ensure it gets some clean air. It probably also doesn’t help to make our wake smaller, giving more drag advantage to cars behind us. This wouldn’t be so bad if we were racing in some sort of sedans only class, but seeing as none of our competition has four doors, and a large percentage are two seaters, this is bad. Unicorn droppings.


We wish the rear glass taper on our car looked like this.

But what’s a boy to do about it all? While it’d be cool to make a car like the NEMO Racing EVO, the reality is the math and engineering required to make a car like that makes our brains hurt quite a bit – we find it patently unfair that Andrew Brilliant’s last name is also a description. Luckily for us, the rulebook limits our options and companies like APR make pre-made aero bits for cars like ours that race in series with rules, so we can let our brains continue to lounge about focusing on reality TV.



Our solution was relatively simple and in line with most of the MPTCC competition: cut some quick panels to block off the rear bumper holes, and add a front splitter, belly pan, and rear wing. Luckily, the rules are fairly easy to comply with in MPTCC: no more than 6” of working surface for the splitter, belly pan is basically unlimited, and any commercially available rear wing, so long as it fits within the OE bodywork (no taller, wider or longer). We’ll experiment with a flat bottom and side skirts later.

Easiest thing first: to close off the holes in the bumper and prevent air from getting trapped in there we simply cut out some coroplast, bolted it in place (Loctite included so we don’t FOD someone’s car) and called it a day.


Coroplast: not just for election day.

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