Air Intake for 88-91 Preludes
Intake Systems Available for the 88-91 Prelude:
Overview:
Out of these, LudeSpeed's intake is probably the best one as it is specifically made for the 3rd generation Prelude. The AEM Type R one, would be next. Then I think the 92-96 Prelude Intake would be third. The least power gains would probably be from the K&N, Weapon R and Civic Intake. I chose the 92-96 Prelude intake because of cost. An AEM CAI for the Type R retails for what? $300? Way too much for me. LudeSpeed's intake is $180 US, and because I didn't know about it when I bought the 4th Gen Prelude's Intake, I didn't get it. Anyways, the intake and filter cost me $120 Can. (about $80 US). It extends right to the front of the engine bay, where the air is somewhat cooler than the air at the stock intake position. Here's how to install it:
Ingredients:
-92-96 (4th gen) Prelude Intake Piping
-Ractive (or other company's) Cone Filter
-Connecting Sleeve (connects intake piping to intake manifold)
-Vacuum Hose (connects intake piping nipple to Cam Cover)
Step One: Removing the stock junk
Remove everything to do with the stock intake system, all the plastic piping, I mean everything. The new intake will be replacing all that junk. You'll also have to remove the battery and installed elsewhere: in the trunk. Instructions for relocating the battery.
Step Two: Putting the intake together
Once room has been made in the engine compartment to fit the intake pipe, install the cone filter onto the end of the intake pipe farthest away from the nipple by attaching it with the supplied hose clamp. Then, install the rubber sleeve on the end of the pipe that will be installed on the throttle body (the end right next to the nipple). The sleeve should be tight, so keep playing with it until it goes on. It should not slide on easily as that would mean that the seal is probably not air tight. The tighter the seal, the less chance there is of a leak.
Step Three: twist/push/twist
Once everuthing is on, the intake will have to be fitted. This is the part of the process that requires some elbow grease because it is not meant for this car. Turn the intake so that the nipple is pointing towards the back left of the engine bay. Then as you fit it under the A/C line, twist it back so that the nipple points up. This is hard to put in words. Basically what I mean is start with the nipple pointing at the ground and as you push it under the A/C line twist it so that the nipple points upwards. If you really don't need or want the A/C line, you could just cut it off. Beware as this is illegal, so do as you like. It would make it way easier to install the intake. The intake does fit with the A/C pipe intact, you just need to do the twist/push/twist thang. Push it down into its final position (see picture). It should be pretty tight, but if you like, you can secure it with a hose clamp or some tie-wraps. My intake touches the fuse box and the end of the filter touches the front part of the engine bay. As it fits pretty tight it won't be going anywhere.
Step Four: Making it work
The final step is to attach the vacuum hose from the nipple on the intake pipe to the one on the head (a similar hose was featured on the stock intake...) and the rubber sleeve onto the intake manifold (this can be a bit tricky but just bend the damn thing until it fits). Be sure to clamp all these down with the provided clamps. Because you removed your battery, you mind as well reset your ECU. If you're pressed for time, it doesn't really matter if you do this, but eventually you should get around to doing it. This resets the ECU allowing it to adapt to your new intake. Verify all electrical connectors that you may have removed, or that may have come undone in the process. As you run the engine, listen for any leaks. Also, check the engine idle speed to make sure it is the same as it was with the stock filter. There should be no change. Pat yourself on the back and go and give the car a test drive. It should sound a bit...well... different at full throttle at about 5000 RPM. Enjoy!
*This procedure is specific to the 1988-1991 Honda Prelude B20A5 engine, but is pretty much the same for any other car. However, you may not need to move the battery to the trunk in all cases. In fact, if the intake was designed for the car you're installing it on, it should not, for any reason, be necessary.