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Snax · 07-18-2019, 06:54 PM

Thanks. Will have to see how well the execution can reflect the idea though.

I'm going to try fiberglass for the skirts if cardboard shows good results there.

Update on the Cd issue after some preliminary testing this afternoon: Wheel spacers suck!

They were apparently responsible for the 0.03 Cd difference from what I just recorded with them removed. At 65 mph, that works out to nearly a 9% hit! I'm going to repeat my testing in wee hours of the morning again to be sure. There was a fair amount of traffic, but after multiple relatively clear stretches the numbers seem valid.

I'm going to leave them off from now on except for autocross and hillclimbs. (Planning on getting some much wider wheels and rubber for that which will not stay on the car much.)

07-18-2019, 06:54 PM	#39 (permalink)
Snax Master EcoModder Join Date: Dec 2008 Location: Eugene, OR, USA Posts: 382 Lord Vader - '15 BMW i3 REx 90 day: 35.06 mpg (US) Thanks: 90 Thanked 170 Times in 126 Posts	Thanks. Will have to see how well the execution can reflect the idea though. I'm going to try fiberglass for the skirts if cardboard shows good results there. Update on the Cd issue after some preliminary testing this afternoon: Wheel spacers suck! They were apparently responsible for the 0.03 Cd difference from what I just recorded with them removed. At 65 mph, that works out to nearly a 9% hit! I'm going to repeat my testing in wee hours of the morning again to be sure. There was a fair amount of traffic, but after multiple relatively clear stretches the numbers seem valid. I'm going to leave them off from now on except for autocross and hillclimbs. (Planning on getting some much wider wheels and rubber for that which will not stay on the car much.) __________________ 2015 BMW i3 REx 2011 Ford Flex SEL AWD Last edited by Snax; 07-18-2019 at 07:04 PM..