[Phase]

Originally Posted by aerohead

I went to TOYOTA's website for the 2024 Prius, and found some pertinent info to add to what we've talked about so far:
A) If the roof apex has been moved rearwards 2-inches, then Toyota has 'shortened' the roofline of the new car, a direct violation of aerodynamics writ large.
B) Even if the entire 1-inch lengthening of the new car is added to the rear, the roofline is still 'stunted.' It's more 'bluff.'
C) The rocker panels on the new car are 'mutilated' by the designer's horizontal character line embossed into the sheet metal, creating a pressure 'kink.' Another violation of 'aerodynamics'
D) The new car body has been widened in the rear, adding 'haunches' for 'stance', and in so doing, destroyed some of the car's facility for pressure recovery; the most important thing with 'aerodynamics.'
E) Both the 17" and 19" tires are P195s, so the frontal areas are identical, and no potential for a difference in drag there.
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BIG NEWS!
F) The Prius SE is the 'ONLY' Prius with Cd 0.27.
G) The Prius Limited & XSE are Cd 0.29.
H) The non-SE cars are 'taller' ( greater ground clearance ), exposing 0.4-inches more tire face to the air.
I) The non-SE cars are 'wider'.
J) Their CdAs are greater
K) Although the new car is reported to be 1-inch greater in length ( 181.1" ), the out-going Prius is 182.9" in length.
L) The engine in the new Prius has an identical 'Brake Thermal Efficiency' ( BTE ) as the out-going model.
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Without a set of blue-prints for the cars, I'm hamstrung, and can't say anything definitive, aerodynamically.

I was reading some scientific studies last night stating that a more slanted windshield angle allows for better attached airflow over the roofline and rear. With this info, that would mean the back of the new Prius has better attached flow on the hatch. Maybe this explains why the spoiler is much smaller than older Priuses?

Knowing the back of the new Prius is shorter and wider, I’m assuming we can drop the CD significantly if the new Prius with a simple tapering extension

I don’t know exact numbers, but I’m guessing even adding just a foot longer tapered box cavity that’s on the sides and roofline would make a huge difference On the cars drag.

You’re pretty much saying that extending the roofline out even just a little bit and continuing down would make a drastic difference?