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Old 01-23-2019, 01:11 PM   #521 (permalink)
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When the vehicle mission is considered (mostly solo tearing about on pavement) SUVs and CUVs, even if they were blessed with Cds equal to, say, Elantras (far from it) are inescapably burdened with excess frontal area.

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Old 01-23-2019, 01:14 PM   #522 (permalink)
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Quote:
Originally Posted by kach22i View Post
I'm guessing this is to prevent critters form jumping up and nesting in the car and crewing up wiring in the process. However I have to imagine there is a small drag penalty.


MORE random pics...... - Page 4685 - Pelican Parts Forums


On a second look, it does not appear to extend the whole length of the under-body.
And the critters that do the most damage are mice, chipmunks, and squirrels. They would all laugh at that.
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Old 01-23-2019, 01:35 PM   #523 (permalink)
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Quote:
Originally Posted by kach22i View Post
What makes you convinced the mpg differences you saw between a Cross-Over and a Sedan were exclusively the results of aerodynamics?
Of course, I never said such as you remarked. I did mention that Elantra was slightly lighter & less powerful than the Caliber, which might tend to give higher MPG. I did like the Dodge 2 liter engine (designed in conjunction with Hyundai & Mitsubishi) for its reliability AND it was very smooth at idle(sometimes people stated they didn't realize the engine was idling) & smooth at speed.
It was NOT known for great efficiency or power, tho. The CVT helped with the lack of 2liter power. Once, while following a very slow car on the on-ramp to a freeway, I shifted to low & swept around the dawdler & onto the freeway, when given the chance. After establishing my normal 60MPH pace in the slow freeway lane, another car who had been behind me on the on-ramp, drove along side me, & gave me a thumbs up for my assertive slow car pass. Yes, from 35MPH, up to highway speeds, the CVT gave the best possible acceleration for a mild engine & excess car weight.
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Old 01-23-2019, 01:56 PM   #524 (permalink)
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Quote:
Originally Posted by litesong View Post
Of course, I never said such as you remarked. I did mention that Elantra was slightly lighter & less powerful than the Caliber, which might tend to give higher MPG.............

Yes, from 35MPH, up to highway speeds, the CVT gave the best possible acceleration for a mild engine & excess car weight.
You write some informative things about your past cars, I was just trying to get to the topic of Random UnAerodynamic Cars and Trucks Thread somehow.

I've long argued that the basic SUV and Crossover profile was better adapted to the aerodynamic template than classic coupes/sedans.

Where SUV's and CUV's they fail is with the roof racks, higher ground clearances, larger frontal areas, drag inducing wheel flares and the like.

I found your comparison intriguing as the Caliber roof is likely to yield better air attachment than the Elantra's, but other factors involved tip the scales.
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Old 01-23-2019, 01:59 PM   #525 (permalink)
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Quote:
Originally Posted by Frank Lee View Post
And the critters that do the most damage are mice, chipmunks, and squirrels. They would all laugh at that.
I agree, the holes are too large to prevent the worst of the critters.

I don't understand what they were trying to do.
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Old 01-23-2019, 07:41 PM   #526 (permalink)
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Quote:
Originally Posted by kach22i View Post
....I've long argued that the basic SUV and Crossover profile was better adapted to the aerodynamic template than classic coupes/sedans.
Where SUV's and CUV's they fail is with the roof racks, higher ground clearances, larger frontal areas, drag inducing wheel flares and the like.
I found your comparison intriguing as the Caliber roof is likely to yield better air attachment than the Elantra's, but other factors involved tip the scales.
Whatever aerodynamic advantages you note in Caliber roof lines & rear ends are always overwhelmed by the draggy Caliber blunt front, compared to Elantra front. Repeating, the wide gap between Caliber & Elantra coefficients of drag are mostly due to the front end differences. Its a bit like the coefficients of drag for bullet shapes. You can give a bullet a drag reducing rear end "boattail" shape to decrease down range velocity losses. But if the front of the bullet is already rounded, flat or hollowpoint, it will lose more velocity than pointed nose shapes.....with or without "boattail" shapes.
Your mention of big "Caliber" wheel flares was interesting. The Caliber EXTERIOR width is about the same as the Elantra's width, in part, due to the wheel flares. However, the Caliber passenger rear seat INTERIOR width is about 1 to 2 inches less than Elantra's rear seat. I've fit 3 adults in the Elantra rear seat easier than seating 3 adults in the Caliber rear seat. The rear seat width is one reason I traded the Caliber for the Elantra.

Last edited by litesong; 01-23-2019 at 07:53 PM..
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Old 01-23-2019, 11:03 PM   #527 (permalink)
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This should probably go in Unicorn Corral:



Hey, if I compromise the interior packaging with a full length tunnel, I will have the World's most efficient and aerodynamic car [send money].

I wish I could make computer graphics like that. Turn on the Closed Captions.
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Old 01-24-2019, 12:37 AM   #528 (permalink)
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Quote:
Originally Posted by kach22i View Post
I like cRiPpLe_rOoStEr's ambulance camper too, and at least it's more aero-freindly than the F-350 8-foot wide box posted in the forum last month.
That campervan was not an ambulance-based conversion, it's a genuine Westfalia. BTW I recently saw a 4WD double-cab F-350 with the 5.4L Triton V8 and a camper module with plates from British Columbia roaming around a neighborhood near where my mom lives.
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Old 01-24-2019, 10:42 AM   #529 (permalink)
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Quote:
Originally Posted by Frank Lee View Post
When the vehicle mission is considered (mostly solo tearing about on pavement) SUVs and CUVs, even if they were blessed with Cds equal to, say, Elantras (far from it) are inescapably burdened with excess frontal area.
You are correct Frank Lee, and you managed to use far less words to get to the point - thanks.

Quote:
Originally Posted by litesong View Post
Whatever aerodynamic advantages you note in Caliber roof lines & rear ends are always overwhelmed by the draggy Caliber blunt front, compared to Elantra front. Repeating, the wide gap between Caliber & Elantra coefficients of drag are mostly due to the front end differences. Its a bit like the coefficients of drag for bullet shapes.
Absolutely wrong.

Drag happens after the highest/widest part of the vehicle, everything in front of that is air pressure build up (>250 mph), but not air compression as in supersonic traveling bullets and over 250 mph.


https://www.grc.nasa.gov/www/k-12/ai.../machrole.html
Quote:
As an aircraft moves through the air, the air molecules near the aircraft are disturbed and move around the aircraft. If the aircraft passes at a low speed, typically less than 250 mph, it is observed that the density of the air remains constant. For higher speeds, some of the energy of the aircraft goes into compressing the air and locally changing the density of the air. This compressibility effect alters the amount of resulting force on the aircraft since the aerodynamic force depends on the air density. The effect becomes more important as speed increases. Near and beyond the speed of sound, about 330 m/s or 760 mph at sea level, small disturbances in the flow are transmitted to other locations isentropically or with constant entropy. Sharp disturbances generate shock waves that affect both the lift and drag of the aircraft, and the flow conditions downstream of the shock wave. On this slide, we will investigate the dependence of the density change on the Mach number of the flow.
When we use the aerodynamic templates the front end of the car/truck is discounted. Please read up on it, it does I admit go against intuition and any feelings developed by prior experiences, it is however based on science/physics.

Aero-template sticky thread:
https://ecomodder.com/forum/showthre...ion-21952.html
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Old 01-24-2019, 10:48 AM   #530 (permalink)
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Quote:
Originally Posted by cRiPpLe_rOoStEr View Post
That campervan was not an ambulance-based conversion, it's a genuine Westfalia.
I thought the term "Westfalia" was only something VW used.

https://en.wikipedia.org/wiki/Westfalia
Quote:
Westfalia-Werke also converted non-Volkswagen vans, and produced trailers and other products, but they were best known for their Volkswagen camper conversions.
I get to learn something everyday, not a bad life.

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