Honda's Explanation of Pumping Loss and Intake length Video

[civic_has]

If you have 9min of free time to kill watch the following video, it provides great explanation of pumping loss, and modifying intake length for optimal length for optimal efficiency (longer length for low end power, and shorter intake for high end power), and other good stuff

http://www.youtube.com/watch?v=OW2uS...&feature=feedu

[TXwaterdog]

btw, thanks for posting this.. I watched it and learned a few things.

[TheEnemy]

I like the way they adjust the intake runner length.

[Old Tele man]

Originally Posted by TheEnemy

I like the way they adjust the intake runner length.

...GM does the samething on the 1.8L engine in the Cruze; 35.8" intake runner length for engine speeds below 4,000 rpm and 10.2" intake runner length for engine speeds above 4,000 rpm.

[tjts1]

So it switches between Otto cycle and Atkinson cycle. This is the engine from the old 2006 Civic which didn't change much with the 2011 model. Just imagine what Honda could do if they implemented direct injection. They've really let themselves fall behind.