2001 Acura CL Type-S Project Car Phase II – Cold Air Intake System

We are well on our way with our project car build, a 2001 Acura CL Type-S. In Phase I we mounted a set of Enkei Klamp wheels in Hyper Black wrapped in Continental ExtremeContact DWS tires. Now we have completed Phase II which involved installing a new air intake system to boost performance and engine efficiency. The folks at Advanced Engine Management were nice enough to provide us with one of their AEM Cold Air Intake systems for our effort. These guys have a well-established name in the Honda and Acura niche for aftermarket accessories and we’ve been anxious to see whether or not these types of bolt-on modifications live up to the claims that circulate in various forums and online enthusiast communities.

Each of AEM’s CAI kits are custom-made for specific years, makes and models and ours was no exception. They are manufactured to replace the factory air box using a soft-mount hardware kit that can be installed in less than 90 minutes. The AEM Cold Air Intake kit consists of an aluminum intake tube, DryFlow filter, a breather hose, water hose and various mounts, clamps and fasteners. This system is designed to place the filter outside of the engine bay where the air is considerably cooler. As such, air mass flow to the engine is increased and the air inlet temperature is decreased. Because cold air is denser than warm air, more power is created during the combustion process. Or so the logic goes…

The nice thing about AEM products, as opposed to some other offerings in the marketplace, is that their intake tubes are made out of lightweight aluminum with a zirconia based powder coat, which makes them not only lighter than their plastic counterparts but ensures better heat insulation and eliminates the potential for cracking. Options typically include four different color choices: blue, silver, polished and red (which is what we received). There is frequently a concern that aftermarket mods are not street-legal, but AEM’s intake systems are C.A.R.B. exempt or pending (aka all good for California), which means that they are legal for use in all 50 states. In addition, AEM offers a full lifetime warranty. These are just a few of the reasons why AEM’s products have such a wide following and why the Company is a market leader..

As I’m currently traveling through Ohio (and all of my tools and equipment are back in California), I am fortunately aware of the one garage who would be able to get the job done right. Simon’s Auto Service in Cleveland Heights specializes in foreign automobiles and has ACE certified mechanics who are top notch. Everyone I know in the area patronizes Simon’s, as the shop is about as honest and trustworthy as you will find in the auto repair business. You won’t have work done needlessly and you’ll get a heads-up when something looks like it’s going to be problematic.

Simon runs his business a bit like a doctor’s office. His technicians perform the majority of the work and he is there for major operations and to make sure that the flow is smooth and efficient and the jobs, themselves, are done carefully and correctly. Dean is a crackerjack mechanic who digs aftermarket modifications and customizations so he was clearly the man for the job. If you ever have some performance parts you want installed and you happen to be in the Cleveland area, definitely stop by Simon’s. Fewer and fewer shops seem to do this kind of work as OEM replacements are the bread and butter of most operations.

So, back to our installation…The process for taking out the old air box and getting ready for the new one was fairly involved but not overly complicated. You don’t need more than a few open-ended wrenches, some metric sockets, a flathead screwdriver and a good jack. However, Simon’s has the benefit of compressed air-driven guns which makes things significantly less taxing.

First, the car had to be lifted up and the left-front wheel removed. The breather hose and water bypass hose assemblies had to be detached along with the upper stock air box assembly, lower front splashguard, inside splashguard and lower stock air box assembly. Then the air inlet tube from the traction control throttle body and air box shield had to be taken off. The most difficult part was the fact that Acura has about 1,672 fasteners holding all of these things in place and removing them was time-consuming.

Finally, with the old parts removed, it was time to bring in the new. This process was much easier and just required a little bit of manual dexterity as these kits never seem to fit absolutely perfect. The connector hose and hose clamps were placed over the traction control throttle body end of the air inlet pipe. The pipe was then attached to the traction control throttle body. There is a support tab towards the middle of the tube which is designed to be attached to the inner fender wall and a special rubber mount was used to anchor it. The DryFlow filter was then placed at the end of the inlet tube and secured with a hose clamp.

Reconnecting the breather hose onto the valve cover breather nipple was a little tricky as the tube had to be rerouted inside the engine bay and cut to fit properly. Reconnecting the water bypass hose also required some creative adjustment. That said, AEM supplies extra tubes for this application along with all of the necessary clamps and, in the grand scheme of things, this was a fairly simple process.

With everything properly in place and all of the well-written instructions followed to a T, it was time to close up the patient. All of the fasteners were tightly secured and the fender liner, front splashguard and left front wheel were all returned to their original places. The tools, excess screws, etc. were removed from the engine compartment and the vehicle was dropped down. I couldn’t help notice the gaping hole where the factory air box used to rest and the massive amount of assembly parts resting on the ground. It’s nice to be able to get rid of the extra weight and free up some room in the engine bay. At that point, about a hour into the process, the mission was accomplished and it was time to check out the end result.

So… is there any change, does it make any cool sounds and can you feel some performance improvement as many people have reported? The answer is Yes, Yes and Yes! At first I didn’t notice any change as the car was still warming up and was just as quiet as when it was stock. However, after a few lights, when I got to a 35 mph zone, I gunned it and heard a cool sucking sound and felt a tad bit more thrust. That peaked my interest and I just had to hop on the highway to really wind it out.

What I noticed is that if you hold 2nd or 3rd gear to around 5,000 RPM the AEM intake has a loud resonance noise that is pretty awesome. And even though there was not much change on the low-end, the mid-range was where I really noticed a difference. If I had to guess I would say that the car probably gets an extra 5 horsepower or so under 5,000 RPMs and then tacks on an additional 5 or more hp into the higher rev ranges. I’ll have to check out the stats on the G-Tech Pro and provide an update later on…

I’m sure there will always be controversy about the efficacy of this type of performance modification but I can honestly say that the AEM Cold Air Intake system for the Acura CL-S provides noticeable boost in the mid and high-end of the power band. The CAI unit is quiet enough for regular driving around town and won’t interfere with either listening to the radio, talking on the phone or conversing with passengers. But when you want to put the pedal down, the AEM CAI unit provides a thrilling sound, solid performance improvements and a little boost to the ego. It also looks pretty cool when the hood’s up! Be prepared to have to stop yourself from flying down residential streets just to hear that nice throaty roar of the engine! And a special thanks again to AEM.

Source: AEM