View Single Post
Old 06-24-2009, 05:06 AM   #29 (permalink)
EcoModding Apprentice
Join Date: Jun 2009
Location: pacific southwest
Posts: 147
Thanks: 7
Thanked 3 Times in 2 Posts
Originally Posted by stevey_frac View Post
Hot air does two things: It lowers the density of air, meaning you have to have your throttle more open to to get the same mass of air, which reduces pumping losses.

It also increases the temperatures of the air going in. Now i know that's obvious, but it's important. Most thermodynamic cycles improve efficiency at higher temperatures.
the more air molecules your induction sys can pump into your filling cylinders
the more power you will make per cycle. you can do so by augmenting airflow
with an optimized air intake tract, ram air or some kind of supercharging. or by chilling your intake air. more air molecules even cooler ones than ambient will be compressed and heated during the compression stroke in a gasser but more pronounced in a autoignition cycle. hotter air burns more readily as rudolf diesel found out almost 100 years ago. that in turn allows you to make more power with fewer rpms, think artificially turning a 4 cyl into v8!
lower rpms --> easier to fill cylinders, and empty them reduced reciprocating and parasitic forces, less frictional related heating (on moving/rubbing sliding parts) additional time for more complete burn... i can keep going.

why not utilize a fourbanger as a V8 and enjoy more power, economy and longevity instead of crippling it and forcing it to perform as a twin?!

heat your fuel like smokey did. he got an 80's chevy to give him 100 mpg?
just be careful if gas is your choice of fuel!
  Reply With Quote