Air Box modification
Former Sponsor
Joined: Jan 2019
Posts: 166
Likes: 28
I connected a 3" hose with 90 degree elbow to rbe side of airbox, piped to that opening in passenger fender. The temp of air coming through there is significantly cooler than air over radiator to stock air horn.
This more than doubles air volume available to box,and gives a nice increase in sound. I paired this with typical interior box mods of removing that elbow duct and reducing height of divider (I left a small ridge to protect against at least some water ingestion).
I plan to later to add a scoop in front of radiator piped to that hose. I may block offstock horn at that time after some experimenting.
This more than doubles air volume available to box,and gives a nice increase in sound. I paired this with typical interior box mods of removing that elbow duct and reducing height of divider (I left a small ridge to protect against at least some water ingestion).
I plan to later to add a scoop in front of radiator piped to that hose. I may block offstock horn at that time after some experimenting.
Former Sponsor
Joined: Jan 2019
Posts: 166
Likes: 28
Believe me I do appreciate the car in stock form. There is some free hidden power in some areas not because Honda Engineers do not know their job but because they have to comply with noise (and emissions in some cases) regulations. Modifying airbox increases power and also enhances the sound of F20C so it's a free win-win modification with zero cost and effect on reliability. Then, why not?
Joined: Oct 2010
Posts: 2,691
Likes: 331
From: Sacramento
Also the stock air box puts a little restriction on the intake, I tested my '06 with a new air filter and I got 8" of water restriction on the intake. Mod the air box and it went to 0" I know its not much and on the street you would never feel it but on the track the stopwatch could tell.
I always wanted to block off the stock opening and with a 6" hole cut in the air box lid mate it to and seal it to the bottom of the hood and finish it off with a small hood scoop for some positive pressure at speed. Good for sunny days on the road or track.
Rod
I always wanted to block off the stock opening and with a 6" hole cut in the air box lid mate it to and seal it to the bottom of the hood and finish it off with a small hood scoop for some positive pressure at speed. Good for sunny days on the road or track.
Rod
Joined: Aug 2012
Posts: 8,759
Likes: 1,859
I thought about the same hood scoop ram air type mod. But the stock hood has a reinforcement right at that spot. Would either have to make an ugly mod to underside of hood, or do some skillful fab work to make it look decent.
Joined: Oct 2010
Posts: 2,691
Likes: 331
From: Sacramento
Thats where a junk hood comes in to play. One that has been bent up in an accident, it doesn't have to look good. One that can be straightened out with a rubber mallet to fit. You want it only for testing(no need to cut a good hood for testing) I would cut the under hood bracing for the hole, mount the hood scoop and see if it moves at high speed. I bet it won't. I would also drill the hood where the under hood bracing is cut and bolt the bracing to the hood. That should keep it strong enough to not bounce around at speed and the hood scoop would cover the bolt heads.
Rod
Rod
Joined: Oct 2010
Posts: 2,691
Likes: 331
From: Sacramento
Oh yes the aesthetic look factor. Been there with a show car, great to look at, not much fun to drive. I suppose I'd take stupid but (fun)ctional over awesome looking. Well, there has to be a breaking point on just how bad of a fun/ugly car I would drive but I'd rather not find out just how bad/ugly that is. LOL
Rod
Rod
Joined: Oct 2010
Posts: 2,691
Likes: 331
From: Sacramento
Well I found ugly, I don't think I'd let anyone see my S with this sticking out of my hood
https://www.intakehoses.com/rubber-e...rt-radius.html
I bet that would grab some air.
Rod
https://www.intakehoses.com/rubber-e...rt-radius.html
I bet that would grab some air.
Rod
