Place Racing Cold Air Intake

One of the best ways to improve the horsepower of an engine is to facilitate the flow of air into the engine and the exhaust emissions out of the engine. The Place Racing Cold Air Intake (CAI) improves air intake in three ways.

First, the pop charger or the K&N filter is installed outside of the engine compartment in the driver's side fender well and protected from splashing and dust by the plastic inner fender liner over the left front tire. Air is picked up from outside the engine compartment. This air can be up to 50 degrees cooler than air picked up in the engine compartment.

Second, the mandrel bent tubing of the CAI significantly improves the flow of air into the engine over the stock intake. The stock intake piping changes in diameter at several junctures causing turbulent air flow. The CAI reduces turbulent air flow since its diameter is a constant 3-inch from the throttle body all the way to the inner fender and the filter.Third, testing on a dynometer has shown that increased pipe length on a CAI causes an increase in horse power produced. This has to do with resonance.

But what is resonance? Simply put When the intake valve opens, air is drawn into the cylinder by its downward movement. When the intake valve closes, the air in the intake is still moving forward towards the valves. It runs up against the closed valve and creates an area of high pressure. This high pressure is then redirected as a wave back up the intake tract away from the engine. When the pressure wave reaches the open end of the intake tract, it reflect back down the tract towards the engine. Now if this wave approaches the valves as they are open, it will help flow more air into the cylinder. The valve closes and the process repeats. This process results in increased volumetric efficiency (more air passing through the engine)...and therefore, more power.

On the left is a picture of the new cold air intake (CAI) that was installed on my SE-R by Place Racing. Gone is the old black air box, the black rubber tube from the throttle body to the MAF sensor, and the diameter restrictive plastic pipe that exits the filter box. There is much more room in the engine bay. The CAI is composed of two pipes the primary that goes from the throttle body to the MAF and the secondary from the MAF to the filter mounted in the wheel well cover. You can either install the primary, the secondary and the filter or the primary with the filter only. When both are installed the reference is to a dry CAI or full stack intake. When the primary and the filter are installed the reference is to a wet or short stack intake. During heavy rain you must take off the secondary and install the filter directly on the MAF in the engine bay.

One day I needed to take my car to the dealer. So I had to dismantle the CAI and install the stock air box. I noticed that the throttle cable, which passes underneath the primary CAI pipe, is rubbing on the underbody of that pipe. The cable was being degraded. What I did is clear in the picture to the left. I wrapped the throttle cable with tape and then hung it above the primary tube by a wire tie attached to the STB. This solved the problem and the throttle cable does touch the primary tube anymore. I advise all those who have a CAI to check on their throttle cable and do this simple fix. The fix spoils the looks of the engine bay but it is better than having to replace your throttle cable.

Installation

If you want to install the CAI yourself here is the procedure that you have to follow. After taking out the stock intake, you must enlarge the hole in the fender well. You need to do that since the secondary is larger in diameter than the stock pipe that attaches to the resonator box that sits in the fender well.

Place Racing provides you with a template so you can make the correct cut. The image to the top-left shows you how to make the cut using a dremel tool. The to the right shows you how the final cut looks. If you want you can sand the edges using a different head for the same dremel tool.

Place Racing also provides you with a protective strip to place around the cut inorder to protect the secondary pipe from scratching and slipping up and down the hole in the fender well. Don't waste your time the strip does not work. The secondary will travel up and down the cut and that will scratch the paint. I have a better alternative. To the left are two strips. The bottom one is Place Racing's. The top one is a strip from a door edge molding. It is intended for the edge of your doors to prevent inadvertent scratching when opening the doors in tight spots. It works great on the cut in the fender well. It has glue inside and it sticks tightly to the cut.

While the strip protects the pipe from scratching it does not protect it from slipping. To do that you need to buy a 1 and 3/4 inch long hose that is three inch in diameter and install it with two clamps at the bottom end of the secondary. When you place the secondary in the fender well the hose will prevent the secondary from moving up and down through the hole. It is a perfect solution. The two images to the right show you how the secondary sits in the fender well. If you ordered your CAI for a POP charger then you will get the hose and the clamps as part of the  kit. However, as in my case, if you ordered a regular CAI then Place Racing does not provide you with the hose or the clamps. When I called Place Racing for a hose and clamps they wanted to charge $26. That is outrageous. Eventually, I went to Long Beach Hose, purchased the piece of hose and installed it with two clamps. Total cost $3.25. This is a remarkably simple solution to hold all secondaries in place and prevent them from sliding into the fender well. 

To the left and right are two pictures of the clean K&N filter as it sits in the fender well. Note that I am pulling on the plastic wheel well cover that protects the filter from water splashes during rain. According to Place Racing you are supposed to switch to the short stack CAI during the rain. Having driven the car during the rain, I believe that the plastic wheel well cover is effective in preventing water from reaching the filter. However, you must avoid deep-water puddles. Moreover, if you drive with the dry CAI set up during the rain you assume full responsibility for the damage to your car. This is simply my experience with my car. I assume no responsibility for the damage to your car that may result from hydrolock.

The CAI was installed on August 31, 1998. Since then I have registered the following impressions:

	The car feels less choked than before. Throttle response is better and the engine revs more willingly than before.
	There is a definite improvement in power across the entire power band. You can feel tugs of torque in the steering wheel when you mash the accelerator while cornering. With the stock intake there was no such phenomenon. This is testimony to the increased power in the car.
	The CAI is less noisy than I expected it to be. At cruising speeds and during normal driving there is no evidence of a CAI. Only at WOT do you hear a deep beautiful growl emanating from the fender well.
	The car feels less powerful on the short stack or wet CAI than it does would with the full stack or dry CAI. I have heard evidence from the mailing list to the contrary.
	I have driven the car during light and moderate rain with the full stack CAI. I have also driven (inadvertently) through a deep puddle. Nothing has happened. I believe that the K&N filter sits high enough in the fender well to prevent water from reaching in. Moreover, the plastic cover that surrounds the wheel well and extends underneath to the front bumper seems to do an effective job in preventing water from reaching the filter and causing hydrolock. Hydrolock is when your the engine sucks water in through the filter. This damages your engine. As such it is very risky to drive with the full stack CAI during heavy rain. Do that at your own risk.