phenryiv1

iTrader: (19)

So in install the Hybrid portion of my PR CAI this weekend and all went relatively well. I put it in temporarily while I wait for my next mod, at which time I will remove the Hybrid for a week or so, then re-install it, then probably go to the full CAI setup.

Here are my thoughts, and some questions:

It is loud- and kinda obnoxious. My wife laughed at it. Even I think it is a bit loud under throttle. At cruising speed, no problem, but the accelleration sound is annoying. WHoever said it sounds like a V8 has not necessarily spent a lot of time riding in a car w/ a V8...
When I make this a true CAI, will the droning noise a) stay the same, b) get better (quieter), or c) get worse (louder)? Also, what makes this so loud? Is the engine noise being transmitted OUT of the intake? Is the sound passing OUT, and the stock resonator stops it, or is this noise created by wind/air buffetting in the intake itself?

The stock hoses are not long enough for the CAI, at least on a 96. meccanoble was right about this, the hoses are not long enough. Try having one come off while driving- car dies. Embarassing, and potentially dangerous. I drove to NAPA and paid $0.76 (with tax) for a peice of heater hose that was long enough to do the trick, but I removed the old hose and took it in with me. When I came out, I was parked on the street. I went to drive 10 feet to the parking lot beside the shop, and thought that I could make it that far without replacing the hose while standing in the road- not the case. Died in the road, popped the hood, slapped the new hose on there (too long) and limped to the parking lot where I promptly cut the hose to the correct length, transferred the clamps, and drove home happy.
LESSON to people doing this install- Do yourselves a favor and spend $1.50 on heater hose BEFORE you try to do the install. Have it on hand and it will make things go a lot better.

Looked over the stock intake system, and I was left with a few new questions.
In looking at the accordian section, I was left wondering why it was considered to be the most restrictive part of the intake? Its diameter at its smallest point is still as wide as the CAI pipes? Is it the turbulence created by the corrogation that makes this the weak link in the intake path?
Same deal with the resonator section. Is it really that restrictive, given that its inner diameter is still 3", just like the my new CAI piping? If diameter playes the biggest role in intake volume, again, I have to ask if it is turbulence that creates the restriction? Kevin asked about the option of a CAI or hybrid setup that removes the stock resonator, while keeping the airbox in place. See his thread here and here.

I propose the opposite: Using the stock midpipe section with a CAI pipe for increased airflow, as well as the benefit of cooler air entering the intake. Any thoughts on this? I could not really understand why this would not be an option, unless there is definitive evidence to explain why a 3" opeining in the stock resonator can be any more restrictive than any iother 3" opening. Of course, I am aware that I may be wrong, so please correct me if this is the case (due to increased turbulence caused by the resonator).

Last comment: THe couplers seem to like to slip. I have had to stop and re-tighten the Breeze clamp that are designed to be super-tight. They keep allowing the filter and MAF to sag and come in contact with the inner fender. I knwo that this will all go away when I do the lower CAI pipe, but it is annoying right now. And NO, I am not just a wussy about tightening it- I can hold my own in the gym (315 pound bench-press @ 151 lb body weight).

mzmtg

iTrader: (11)

The noise is from the engine itself. The purpose of the complicated intake systems from the factory is specifically to control that noise. It shouldn't drone noticeably at cruising speeds, only when the throttle is opened a lot.

The restriction of the stock "mid-pipe" comes from the turbulence. Even though the diameter of the main path is large, all of the other protrusions and cavities slow down the airflow.

Using the stock mid-pipe and the rest of the CAI piping would not make a big difference in the noise. Just as adding a hybrid midpipe to an existing open style filter does not ake a significant change in the noise. Most of the muffling comes from the stock airbox.

The full CAI setup is not as loud inside the car as the hybrid setup. This is due to the fact that the filter is located farther from the driver. But, it's still pretty loud.

Lime

Outside the car ... both are pretty dang loud!

Jamsan

iTrader: (2)

inside the car, my hybrid is loud as all hell...inside the car with cai, it seemed alot lower (obviously due to the location of the filter)...ive never heard a CAI from the outside, only when racing one, so i really coudlnt tell from that....i still love my hybrid

phenryiv1

iTrader: (19)

Sadly enough, I am feeling old after this mod. I actually LIKE my maxima how it was. Sure, I wish it was a bit faster, but in the cost/benefit analysis of this mod, the gain (a few HP) just does not outweight the costs (more than just a few dB in cabin-noise, as well as the financial cost of the PR CAI itself).

I guess it to each his (or her) own. After I test the UDP with and w/o this mod, I may sell the CAI.