Well, after nearly two years of exhaustive S2000 CAI musings/testing, etc, the list of do's and do nots when it comes to intake design have suddenly become much clearer. Down here in Miami, as the longtime S2000 locals here will surely tell ya, the humidity and heat take their toll on intakes. The changes are so well defined that I can tell when my car runs stronger in the evening (after the freakin' sun goes down and temps get down into the 80's).
Figuring I needed to find some way to DECREASE these ill-effects, I began to ponder if the heat shield surrounding the filter was doing more harm than good when it came to air flow. I suspected because of the setup pictured below, from idle or low rpm roll-ons, the filter was not getting enough air from the duct which really only has a useful purpose at speed. I noticed the same effects with my PRM, no matter what I did to it. Afterall, the OEM design of the canister never was messed with so to make this post shorter (than normal), I removed the plastic cover and wouldn't you know it....the bog and general malase of the car at low rpm seemed to disappear.
One would think because I've opened the filter up to higher heat soak conditions as a result of its exposure (despite the heat shield), the car picked up throttle response with the heat shield removed. At speed, it lost nothing. After removing the heat shield, I re-connected the ducting so it leads directly into the filter. More air flow down low, same air flow up top (if not slightly more due to the filter now being completely open).
Conclusion? If you're going to protect your filter with a heat shield, a housing similar to Comptech's Carbon Fiber topped airbox or K&N's wrapped enclosure which STILL allows some room between the shield and filter is the way to go. Hell, even the OEM airbox with the right ducting is more than acceptable (remove those baffles however). It is now my belief that heat shields which only allow air to enter the filter from one direction (in front of it, as opposed to 360-degrees) are a compromise down low. At speeds, those negatives began to disappear but this more than explains why no matter what I did to my PRM, that low rpm bog wouldn't disappear. The same with my Weapon R with the plastic heat shield that completely enclosed the filter sans for the top of it. It suffocates the intake. My previous Comptech-Racing Akimoto intake performed better down low than this Weapon R (until I removed the shield) and now I know why. It had an exposed filter. Up high, the Weapon R performs even better because of the ducting.
Bottom line? I will never buy another intake that wraps around the filter like a plastic or carbon fiber condom. Not enough air at low rpm.
Next up? Home Depot to make me an airbox.
I realize it's crazy to think a short ram could be an effective S2000 intake but I've literally had 'em all save for the Mugen-style and for some reason, if properly shielded, they work amazingly well with the filter exposed. I would never have believed it but the Tazzo doesn't lie. I suspect the reason can be mainly attributed to flow rates from the shorter tube and the ducting from the front of the car.

 

My friend has the same intake. He put a heatshield on that he bought from Autozone. It is one loud intake!!

 

any numbers?

 

Not yet. Haven't scheduled a dyno run but it wouldn't reveal much other than what the car is making now. I use my Tazzo to chart performance differences, especially when it comes to intakes. A dyno run won't reveal much from the changes in this case, especially if the heart of the system requires forced air from the front of the car, something a fan won't mimic with accuracy. I have a list of Tazzo runs with a lot of 13.7x's so I'm satisfied the car is running fine. I don't drag the car so I'm not interested in taking it to a strip...I use the Taz to make sure I'm not, like a doctor, causing my patient HARM. I really don't even use the 1/4-mile as a barometer, rather the single gear speed test. The Tazzo will chart your times from 30-70mph in 3rd gear. Very helpful.