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brucepick · 03-07-2009, 07:56 PM

I finally decided I REALLY need HAI or at least WAI as intake temps below about 35-40 degrees F seem to prevent the car from going into lean burn mode.

Well I did it today. Easy to do, once I realized how. Cut openings in bottom and driver's side of air filter box, to let it pull air that's passed through the radiator. Success! Normally the intake air temp (IAT) has been 10-15 degrees above ambient, once the car warms up. With the new openings cut and the original tube blocked, temperatures were fully 30 degrees above ambient for highway cruising. Those intake temps were very stable too, in spite of hills and all the needed throttle changes. In town with stop and go traffic and errand stops, temps went about 40-50 above ambient.

This should be warm enough to get me lean burn even when outside temperatures go down to about 10-20 deg F. I'm not sure about wet weather though. Wet weather seems to also snafu the chances of running in lean burn mode; I'll just have to see how that goes.

The usual HAI / WAI method is to run a tube to the exhaust manifold. However that path is crowded on this car, especially if you want to pull air into the original open end of the intake system (I gave up on using the original opening though).

Easy method on this car: Cut openings in the bottom and driver's side of the airbox. In first photo below, yellow oval shows location of original intake port. Green arrows show where I cut openings in filter box. I used a Dremel type grinder (Black and Decker, actually) with a small cutoff wheel.

Openings at green arrows pull in air preheated by the radiator (photo above).

This photo below shows the locator tabs at front of air box widened by grinder. Pry tab jaws apart with a flat blade and cut away some plastic to be able to get the thing out of the car. Then widen and clean up the cuts a bit once it's free.

Here's a closeup of the cuts I made. I also blocked off the original intake port near fender with duct tape. You can add/remove tape where needed to adjust the amounts of hot/cold air.

Here's one more: Looking down into the air box. Top of pic is the forward/front end of air box.

03-07-2009, 07:56 PM	#1 (permalink)
brucepick OCD Master EcoModder Join Date: Dec 2007 Location: Eastern CT, USA Posts: 1,936 Outasight - '00 Honda Insight Team Honda Gen-1 Insights 90 day: 54.18 mpg (US) Thanks: 431 Thanked 396 Times in 264 Posts	Quick HAI/WAI for '97 Civic HX I finally decided I REALLY need HAI or at least WAI as intake temps below about 35-40 degrees F seem to prevent the car from going into lean burn mode. Well I did it today. Easy to do, once I realized how. Cut openings in bottom and driver's side of air filter box, to let it pull air that's passed through the radiator. Success! Normally the intake air temp (IAT) has been 10-15 degrees above ambient, once the car warms up. With the new openings cut and the original tube blocked, temperatures were fully 30 degrees above ambient for highway cruising. Those intake temps were very stable too, in spite of hills and all the needed throttle changes. In town with stop and go traffic and errand stops, temps went about 40-50 above ambient. This should be warm enough to get me lean burn even when outside temperatures go down to about 10-20 deg F. I'm not sure about wet weather though. Wet weather seems to also snafu the chances of running in lean burn mode; I'll just have to see how that goes. The usual HAI / WAI method is to run a tube to the exhaust manifold. However that path is crowded on this car, especially if you want to pull air into the original open end of the intake system (I gave up on using the original opening though). Easy method on this car: Cut openings in the bottom and driver's side of the airbox. In first photo below, yellow oval shows location of original intake port. Green arrows show where I cut openings in filter box. I used a Dremel type grinder (Black and Decker, actually) with a small cutoff wheel. Openings at green arrows pull in air preheated by the radiator (photo above). This photo below shows the locator tabs at front of air box widened by grinder. Pry tab jaws apart with a flat blade and cut away some plastic to be able to get the thing out of the car. Then widen and clean up the cuts a bit once it's free. Here's a closeup of the cuts I made. I also blocked off the original intake port near fender with duct tape. You can add/remove tape where needed to adjust the amounts of hot/cold air. Here's one more: Looking down into the air box. Top of pic is the forward/front end of air box. __________________ Coast long and prosper. Driving '00 Honda Insight, acquired Feb 2016. Last edited by brucepick; 12-08-2011 at 11:49 PM..