Coupe aero testing

[jkrueger]

I did some driving tests yesterday with the coupe. I taped on some yarn tuffs in places on the body that I was curious about the airflow. I also did the tests with and without the front nose spoiler we made on radiator duct outlet. I also looked at the airflow on the side of the car with and with out the quarter window scoops.

Bear with me because I didn't get the camera in the same exact position when switching configurations and of course I didn't have my spell checker on either.

Let me know what conclusions you guys come to. The goal is to make the car more slippery, build in some engine compartment cooling, and cockpit cooling.

My observations were that with or without the nose spoiler, there is a lot of turbulence behind the radiator duct outlet and the windshield. The air seems to flow better over the front part of the duct outlet without the spoiler. Air flow in the duct doesn't seem to change with or without the spoiler. The air on either side of the hood bubble seems very turbulent, right where I would want to put hood louvers. The hood side vents seem to be sucking in air instead of letting hot air out. The air by the side windows seems smoother without the quarter window scoops and the quarter windows seem to let air in even without the scoops (must be a lower pressure inside the cockpit). I don't understand the air flow over the rear spoiler.

https://www.youtube.com/watch?v=m-BnzzlLpqs

[Jacob McCrea]

This is all pretty far outside of my expertise, but with that said, I have to wonder if the air coming up out of the radiator creates what looks like turbulence around the hood bulge. Also, I wonder if eliminating that hood bulge, as blasphemous as that may be, would help air flow?

Thanks for sharing this J.C. I hope all's well with you and your family.

[tirod]

There's likely going to be a reversion at the base of the windshield regardless. The Trans Am sedans plumbed their cowl induction intake there to take advantage of the higher pressure. Looking at the GT40 and progression of shapes in Le Mans coupes, the designers keep curving the windshield back more and more to cut down the dam effect that the glass creates. Coupes use Jag glass, it's pretty flat and upright, but it added 40mph to the Mulsanne straight.

Not surprising to see the air going in the side vents - it's trying to fill low pressure under the car. The radiator is exhausting out of the envelope and there's a "void" it's trying to fill, like a paper cup flying bottom first thru the air.

Am I seeing that the driver can actually reach across the cockpit and close the opposite windows? Wow, that's a reality check, still getting an idea of how small these are.

Nice seeing the air laying down tufts so low on the back glass, it's doing what PB meant it to do.

Thank you very much for the work and video.