frederickcook87

phatz

crazy time!
that lowers the temporal displacement to 88

ScootCherHienie

I don't know what to say. Honestly, if you block every hole in the front of the vehicle and make the whole nose smooth and rounded, you might see MAYBE a half-mile-a-gallon improvement in a vehicle like a Cayenne... if the car doesn't overheat first. Opening "holes" in the front of the car does NOT improve aerodynamics or MPG. You create more turbulence with the holes open than when they are closed and turbulence is not aerodynamically efficient.

Avec

Assuming the OP actually IS seeing an MPG increase, it could be because this is lowering the temperature of incoming air, not any aerodynamic effect. I did something similar with my now deceased TD Suburban. Took out a turn signal from below the headlight and replaced with pierced metal. The lowered the temp of the incoming air quite a bit, and I got noticeably better mileage. As this was a well-traveled road horse, I noticed when and for what reason mileage changed.

frederickcook87

frederickcook87

ScootCherHienie

Cold air does not improve MPG in cruise conditions. The mass air flow sensor will detect higher density air (when the air is colder) and increase the duty cycle on fuel injectors to add more fuel to compensate for the denser air. The cold air can possibly improve performance slightly, but it will not improve MPG on the highway or lower-speed steady-state driving. Something as insignificant as a change in the average wind direction changing between 2 fuel fillups will change MPG more than opening an intake to get cooler air into the engine.

frederickcook87

slavie

Yes, BUT then you let off the gas a little because now you need less throttle to maintain the same power and speed levels, and you're down to the previous levels of fuel injection.

It is statistically impossible to prove that you got better fuel economy based on 2 fuel ups. There are way, way too many variables that could have caused your increased fuel economy - gas at the pump changes (various levels of ethanol, summer/winter gas mixes, etc), air temperature, wind direction as mentioned, etc. If you get the increased fuel economy over 10-15 fuel ups, then you can start getting excited.

ScootCherHienie

Nobody using pump fill-ups can produce accurate MPGs.Govt mandated MPG ratings are done indoors on dynamometers with controlled temperatures and vehicle loads and automated application of gas and brakes... and precise fuel measurements. You simply cannot replicate that in real-world fill-up to fill-up calculations. You cannot replicate everything. Your calculartions are not lying, the problem is everything that happens BETWEEN fillups that invalidates the calculations. Especially when you are talking about results of 10% or less difference. Sorry you didn't know about cold air making it impossible to get better gas mileage. I've known that since college... about 1968, when I was a freshman with an automotive engineering major. And again in the mid-1970s when I studied Bosch K-jetronic mechanical fuel injection, and again in the 1980s with early computerized fuel injection systems, and again in the 1990s when more sophisticated fuel injection appeared, and again in 2010 when direct injection systems were getting widespread and relied on 1 coil per cylinder. We proved it in automotive lab in Freshman year using a single cylinder research engine that allowed you to view inside the combustion chamber through a quartz window, change compression ratios while the engine was running, change intake and exhaust valve timing while the engine runs, adjust spark advance and the curve while the engine was running, and used a lab-grade fuel tank with highly accurate gradations. You could even purge all fuel from the carburetor so the tank was the only source of fuel for tests (no residual fuel in the float bowl.

frederickcook87

ScootCherHienie

If you come across as not understanding something, which you did, you are going to get information so you do understand. If you find that abrasive... whatever. You can read whatever you want into posts others make in reply to your posts, but that doesn't mean there was anything in other posts that was intended to be abrasive, it only means you chose to take the post that way. Again, whatever. The only reason I included the information about how I know this, is because the next step in these "Guess what I figured out" "Oh no you di-in't" threads would be questioning my "credentials" and accusing me of arguing for the sake of arguing. I was done posting to this thread so I included "credentials." in hopes of nipping further replies in the bud. If I wanted to be abrasive, I could have said something like "Any credible source found in 10 seconds via internet search will confirm that colder air does not improve MPG." THAT would have been abrasive. And there were additional posts in the thread supporting the non-fact/fake-news that cold air improves MPG. And just to be complete, I never said cold air induction doesn't improve ANYTHING as posted in this thread. I said cold air doesn't increase MPG. Acceleration/top speed... cold air can definitely make a small improvement there and even more of an improvement if the fuel map is updated to increase fuel as speeds increase and more and more cool air gets into the intake in higher gears/speeds, say above 50-60 mph and at higher engine RPMs.

frederickcook87

ScootCherHienie

college freshman in 1968. I was in an automotive engineering co-op program, 5 years, averaged 35 to 40 class hours per week, Monday - Friday and half a day on Saturday with very few "off" hours. Same curriculum as MIT but I had 12 weeks to finish the work they did in 18 week semesters at MIT. First year at Pontiac Motor Division in Pontiac, MI, rest of the years working at GM Tech Center where I saw Zora Arkus Duntov, John Delorian, and Bill Mitchell periodically. The best thing I learned in college was that I never wanted to work for GM, Ford, or Chrysler back in the 70s when I graduated... MAN were they messed up companies! I saw some interesting stuff, really interesting stuff... I ran CAD on a computer terminal with a light pen in 1970 something very advanced and rare at that time, but I also wrote programs in Fortran on punch cards, tech from the 1950s that was pretty much obsolete by 1970 but was still used to make full-size drawings of cars on huge x-y plotters... bizarre stuff. If management hadn't had their heads so far up their butts that they could still breathe, I'm sure I'd have retired from GM. Best part was they paid me while I worked roughly half the year and that paid for tuition, rent, food, transportation, clothes... all I hit my parents up for was a $500 car (a '62 Buick LeSabre 4 door hardtop) so I could get back and forth between work and school and move all my stuff when I switched from school to work and back. No debt when I graduated, but it was BRUTAL... 500-something people in the freshman class (3 girls), 115 in the graduating class (last girl gone at end of first sophomore semester).

J'sWorld

Wow.