View Single Post
Old 03-15-2018, 01:09 PM   #19 (permalink)
Ecky
Master EcoModder
 
Ecky's Avatar
 
Join Date: Dec 2011
Location: New Zealand
Posts: 5,005

ND Miata - '15 Mazda MX-5 Special Package
90 day: 42.54 mpg (US)
Thanks: 2,866
Thanked 2,501 Times in 1,547 Posts
Quote:
Originally Posted by mpg_numbers_guy View Post
True. Almost seems like the hybrid system does nothing for the fuel economy.
For the most part, it doesn't. I have it unplugged in my Insight right now, running on gas only until I can get a replacement part for my IMA battery. Fuel economy is virtually the same, except in some stop-and-go situations, which are rare where I live. What's different, however, is that the 0-60 time is just about doubled. The hybrid system allows for the use of a smaller, more efficient engine than you could otherwise put in a vehicle, because it would be dangerously slow.


Quote:
Originally Posted by mpg_numbers_guy View Post
Sounds like a much easier solution...how complicated is it? Cost estimate?
Probably $5-700? The Hondata ECU plugs right in where you old one was, but you need a tuner to program it.


Quote:
Originally Posted by mpg_numbers_guy View Post
Lol, does sound like a good comparison. If only there was an "easy" way to drastically increase MPG...but if there were then automakers would most likely already be implementing it.
Pretty much. It helps to look at where the losses are.

Aerodynamics - A smaller car with a tapered rear end improves highway economy. People are increasingly buying larger, more boxy vehicles, despite more aerodynamic cars sitting next to them on lots.

Weight - Smaller, lighter vehicles improve city economy, since it's less mass to accelerate and stop. People want larger, heavier vehicles.

Transmissions - Manuals are less lossy than autos (usually). Nobody wants to shift gears, manuals are disappearing.

Engines - Smaller engines have less internal friction, and smaller parasitic losses. People want faster cars, and are buying bigger engines.

Tires - Narrower, lower rolling resistance tires improve economy. People want more grip for safer, higher speed cornering, and buy bigger, stickier tires.

~

Hybrid systems address a lot of these things, for various reasons. You can have a smaller engine without sacrificing power. You can have an automatic transmission with low losses (read about Toyota's planetary gearset in the Prius). You can use batteries to capture some of that energy lost in braking a heavier vehicle. You can get rid of some of the more lossy components in cars, such as alternators. It doesn't solve the aerodynamics or tire problems, but it helps.
  Reply With Quote