After stumbling upon Hobbit's site, I'm not so convinced that a warm-air intake mod is beneficial to fuel economy in the Prius: http://techno-fandom.org/~hobbit/cars/warmair/
<div class='quotetop'>QUOTE(David Beale @ Sep 13 2007, 03:29 PM) [snapback]512103[/snapback]</div> The last time I looked at my classic intake - it is a TBI -- which is a throttle body with an intake runner to the intake valves .. i have not seen a direct port injection on the prius --- i think you're thinking of another car .. the fine mist is not right at the valve opening by the injector, rather the mist travels the length of the aluminum intake runner. i would thinkyou would know that if u had a prius and spent a little time observing under the hood.
yea warm air isnt beneficial to fuel economy, i took off the hose from the air filter box to the resonator, and discovered the exhaust note is louder, but the fuel economy dropped. Routing the hose to the grille brings some improvement.
Anyone try removing the charcoal filter that resides inside the airbox lid? It is very restrictive to airflow into the engine and removing it was a big thing on the Tacoma forums a couple years ago when they first started showing up. It increased engine responsiveness and performance. Yeah, I know what it's for and its removal wouldn't be very environmentaly friendly.........But someone will do it eventually.
Hmmmm.....I think Beale's correct at least on my 07. Is the classic using a TBI system? TBI means throttle body injection where fuel & air is combined at the throttle body. Not so on the 07. On my 07 it uses a throttle body that manages just air and at the end of the aluminum intake there is a fuel injector which injects fuel right at the valve area exactly as Beale stated. I know because I have spent a little time observing under my hood.