Getting more MPG's out of a non-hybrid with aerodynamic tech from the Prius?

At 60 MPH, I would guess that you would see little difference. You would probably be better served by changing to the CE wheels and tires. You might drop by ecomodder.com and see what those guys have to say. They discuss aero mods on non-hybrids all the time.

 

Yes, get rid of that oversized spoiler. Just remember that at high speed against a headwind the rear end will get a bit light because of the increased aerodynamic lift.

If you have an accurate engine coolant temperature gauge and monitor it carefully, you can partially block the grill by varying amounts depending on weather and driving conditions. There are plenty of threads about that. If you have easy access to the backside of the grill, you can block it there so it doesn't affect the looks.
The principle behind that, is that it takes less energy to push the air around the car than through the radiator. Grill blocking also has the additional benefit of keeping the engine slightly warmer in winter, thereby reducing friction.

Nice flat wheel covers or wheels, with few spokes, also help a tiny little bit. But make sure there is enough airflow around the brakes to keep them fom overheating.

 

My guess, and it is only a guess is the best thing you can do is fit low rolling resistance tyres, pump them up to the sidewall pressure, minus 2 psi on the back. A spoiler which is contiguous with the boot lid has to give lower wind resistance, but I think it would be minor. A block heater if you live in a cold climate would be good value. How about moon domes?

No mod works better than a driver behaviour mod.

 

I'm sorry, but you have the concept of grill blocking wrong. The reason for grill blocking has nothing to do with aerodynamics or "reduced friction"! The reason to block the grill is to allow the engine to warm up quicker (and indeed warm up at all!) and therefore run MUCH more efficiently. A ICE doesn't begin to run efficiently untl ~190f. The Prius struggle to get to that temp, even in warm climates.

Some benefit may result in doing the same with corrolla, but the effects would be less as the ICE runs all the time, and therefor gets and stays warm easier.

Icarus

 

Hi Icarus, actually I understand the concept of grill blocking very well.
But the OP asked about the aerodynamics of a non hybrid car.
There are aerodynamic benefits from grill blocking on a non hybrid car.
So I told him about the aerodynamic benefits of grill blocking on a non hybrid car, because he asked about aerodynamics on a non hybrid car.

I had been doing grill blocking for about fifteen years on my former non hybrid cars also. In winter I had an increase of about one to two mpg with grill blocking, compared to without.

Yes, I admit that I neglected to also mention all of the other benefits of grill blocking on non hybrid cars, such as the slightly improved combustion efficiency during warmup, and the slightly reduced pumping losses. Not because I "have the concept of grill blocking wrong", but because I concentrated on answering the question that was asked.

He asked about aerodynamics. I answered about aerodynamics.

 

Grill blocking for aerodynamics is likely to be far less effective than for winter temperature control.

The OP is probably correct about the spoiler. Spoilers are for high speed downforce. If one is not running near/at/above triple digits the benefits are questionable...especially if you aren't trying to corner at such speeds. At 130+ mph (speed limiter removed...and a few other mods, had to use the tach to determine speed past 110) my 240SX was still accelerating and felt well enough planted. It had a small spoiler and very low Cd for the time (.29 in '91.)

The advice about pumping up the tires is not aerodynamic in nature, but most likely true for efficiency (minimizing rolling resistance.) Look at the placard pressures for the Corolla, then use the same pressure offset front to rear and use the sidewall pressure for the maximum setting. This might handle differently in wet conditions, so after changing the pressure drive cautiously until you have adequate feel for cornering/handling characteristics (as you would in a new vehicle or new set of tires.)

If your Corolla already has more than sufficient ground clearance then lowering springs might make some sense. (I'm more a fan of stiffer suspension.)

 

I suspect, though I have no evidence to support it, but I suspect that conventional grill blocking will have almost zero effect on fuel economy due to cleaner air flow. If you were to sculpt and install a "clean" front from front bumper to windscreen you might have some effect. On the other hand, the drag caused by air under the car would probably have a worse effect on drag. Of course, the ICE needs some air for combustion as well as some for cooling. The ideal radiator would be one that ran coolant through a thin smooth surface. The object of the radiator is to increase the net cooling area (fins).

So I contend that grill blocking might have some fuel mileage effect on a Corrolla, but the benefit would come from more efficient operating temperatures rather than any "real" aerodynamic improvement.

Icarus

 

If you are really serious about aerodynamic mods, have you read up on the AeroCivic? The owner is a frequent poster on the hypermiling forums, and can pull 95 mpg at 65 mph. This may be an excessive mod level to apply to a new car, but you could pick up some lower level ideas from it.

 

I never said grill blocking would work aerodynamic wonders, but it definitely has an aerodynamic effect. In winter probably about on par with ditching the oversized spoiler.

But anyway, aerodynamics or not: It works. It also works on non hybrid cars. And it's a good bang for your buck.


Optional reading:

The problem is not the turbulence caused by the grill on the outside of the car, it's the air that goes through the grill. Most of the air that goes through the grill then goes through the radiator, hits the fan, hits the engine and transmission, and whatever makes it around eventually hits the firewall.
So, most of the air that goes through the grill into the engine compartment is being accelerated (or braked depending on your frame of reference) up to nearly 60 mph before being dumped out the bottom. In contrast, most of the air outside the car flows much more smoothly.

The grills on the Corolla are around ten percent of the frontal area.


Mercedes E-Class Coupe – Slickest production vehicle in the world - CleanMPG Forums

for more details see also The 2010 Mercedes-Benz E-Class: BlueEFFICIENCY Technology | eMercedesBenz - The Unofficial Mercedes-Benz Weblog


http://www.aeromech.usyd.edu.au/15afmc/proceedings/papers/AFMC00216.pdf

Car Aerodynamics

Efficient Radiator - Tech Articles - Stock Car Racing Magazine

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F-150 GAINS FUEL EFFICIENCY AND AERODYNAMICS WHILE BEEFING UP TOUGH TRUCK IMAGE | Ford Motor Company Newsroom

http://autospeed.com/cms/title_Low-Drag-Car-Aerodynamics/A_109778/article.html

 

I have long lobbied Toyota to include T-stat controlled shutters ala big trucks on the front of Prius'. It seems like a no brainer, and if as you suggest that some considerable aerodynamic ef is gained, so much the better.

Icarus

 

BMW also fit shutters on their 1 and 3 series petrol-engined cars (not Sport or M Sport models), and on all 5 series (again, not M Sport), in Europe. This Active Aerodynamics feature is also on some 6 and 7 series, and on some X3, X5 and X6 models. (I couldn't work out the pattern.)