OK -- here's the premise. After messing around with hot-air intakes, warm-air intakes, and cold-air intakes, it turns out that none of the above will work for my application. A combination is needed with the radical changes in ambient temperature experienced in this region.
Background Testing: Using the 1998 Acura Integra LS Automatic test vehicle, seperate tests have shown that at the same speed, road and wind conditions, 50F air at 20% TPS results in 25 mpg, 90F at 20% TPS yields 33 mpg, and 120F+ at 20% attains 28 mpg and reduced performance with pre-ignition/detonation unless a higher octane fuel is used. Air colder than 50F reduces FE linearly. It is apparent that a constant intake air temp of 80-90F should increase available power and highest engine efficiency from this variable.
Hypothesis: Based on fuel maps for my application, a switched intake to draw cool outside air and warm/hot air from 2 separate sources will hold the intake air at a pre-determined temperature range of 80-90F, using either a manual switching mechanism, or a fully-automatic control module using the IAT sensor.
Implementation: This is where I need help.
Cold Air -- I found a conveniently removable plasctic notch in the wiper tray area where the hood seals the engine compartment near the battery, that exposes a 1-inch tall slot by 12-inches long. This could be the "cold air source" although this is usually a "dead air space" at speed. Otherwise, a notch could be cut into the right turn signal to draw outside air directly from the front of the vehicle.
Hot Air -- bit of a specialty of mine. I've been able to draw up to 220F actual IAT temps off of the exhaust manifold. This is the target location.
Control System -- I have no idea. MetroMPG mentioned that a Honda Insight owner developed a completely automatic system, but I did a deep search on the site mentioned and through search engines I wasn't able to find anything. There are 2 ways to approach:
- Manual: The driver controls a knob or to direct the intake air based on ScanGauge values
- Automatic: The IAT signal is tapped, and wired into a circuit board that interprets the signal to control the valves.
Valves, Piping, and Fail-Safe -- So, what kind of valves and piping are available for this application? I've performed some DIY plumbing repairs and know PVC fairly well, but it all comes down the valve type and how it works. Any suggestions? Lastly, a fail-safe mechanism should be implemented so intake air isn't inadvertently choked-off partially or completely: in either automatic or manual mode. Each valve's closure should be offset by the other valve's opening (for example if the hot-air valve is open at 80%, the cold air valve is open at 20% to ensure 100% air flow).
Climate -- Kansas City is known for its extreme temps. In the last 365 days, outside temps have ranged from -1*F to 107*F; thus enhancing the importance of a more controlled environment for this OBD-II system.
Personal Statement -- This has been on my mind as a project for quite some time. With the cold weather, I need hot air on startup to prevent running rich or in open loop for extended periods, and once up to temp, a slight cooling of the air is required to keep it out of the 100F+ range (which has been happening in temps as low as 30F ambient outside). When in that sweet spot of 90F IAT, I've achieved superior in-town FE as indicated by the ScanGauge.
Plea for Help -- Any engineers, folks with this experience, or brainstormers that can help figure this out? All piping will terminate to the airbox where a K&N cone filter can allow any cutting or compromising of the box itself.
Thanks in advance for the advancement of Science and FE!