BlackSpec02

iTrader: (17)

nice, does anyone have a dyno w/ a cold air?

alpine

I had a pop charger.

It was nice.

I now have the K&N Typhoon

It's better.

More, not as loud as the pop charger was but it has a nicer sound. I know some of you just want more noise, so if you want more noise Vs. more performance, get/stay with POP.

Anything that is going to grab colder air out in front of the car, with more air force, has got to be better than anything residing in the engine compartment drawing in heated engine air, with or w/o heat shield.

Here is my Dyno run with that setup, now I don't know how much the K&N was helping but my car did above average, and over most of the cars which had exhaust (at that time I didn't have exhaust) and several other modifications.

jreiter

iTrader: (6)

One thing you have to remember about dynos is that they almost never have as much air flow hitting the front of the car as you would if you were on the road. Very few shops have fans huge enough to simulate a 40 or 50 mph wind on the front of the car. When you're talking about cold air intakes vs hot air intakes vs stock, wind speed makes a major difference.

Another important thing to consider is that dynos are performed with the hood opened. In that scenario, a hot air intake is mostly going to be drawing in cold room air just like a CAI or stock intake would. Now, close that hood and that HAI will be drawing in hot engine bay air. This could be one of the reasons why HAIs work so well in dyno tests, but generally don't show the same results in the real world.

A real test of this would be to run dynos with the hood closed, and a fan in front of the car that can move enough air to simulate some desired velocity. Another great test is exactly what Chazzg did by driving around in the real world with different intakes installed, measuring the air temperatures.

Remember that I'm not talking about the maximum flow that a filter can achieve. I'm just talking about intake temps.

Gsedan35

iTrader: (10)

Factual MAF intake air temp readings show that the oem system IS a CAI, and that long tube CAI's bring in the same air temps as the oem system does.

I have the K&N 350Z Typhon, but was suprised by a number of design flaws that were serious enough to push me to correct them.



I killed off the awfull hole in the filter box, converted the lid to seal, it now feeds from the bumber with all 3" piping, has a open top K&N filter, and is fully insulated with fiberglass and reflective wrap. If I knew in advance all the things I had to change, I wouldn't have even been interested in it at ALL. Even with the rework, it only best's the oem intake by a few degree's, simply not going to make more power on account of air temps. Even though mine has been converted to copy the oem system and pressurise, it's not enough to effect power.

jreiter

iTrader: (6)

Absolutely. This is why I personally tell people that, if they are in it purely for performance, don't bother with an aftermarket intake on a 350Z. Waste of money and won't get you a darn thing in the real world. (Other cars can be a different story, though, depending on how poor their stock intakes are.)

However, if you are in it for the sound (which is very cool, if you ask me), then aftermarket intakes actually accomplish something. My Nismo intake sounds phenomenal at high rpms. I recently switched back to the stock intake (for testing purposes), and I'm very unhappy with how tame it sounds in comparison.

Granted, $150 or more for nothing but a sound change is a bit silly, but if you've got the money to burn... why not?

xxlbeerZ

iTrader: (8)

I remember some guy was making a kit using a drop in filter and piping to replace the stock flex pipe. Did that ever get made? I think that would be the best solution...

jreiter

iTrader: (6)

I agree. It would seem that, for purely performance related goals, optimizing the stock intake will be easiest and most effective. A higher flowing drop in filter and smoothing out the intake tube would probably be the two items to address and are both simple.

In my mind, there are two things to watch out for:

1) Aftermarket drop-in filters don't always flow better than stock paper filters. With the filters used by my Audi A4, laboratory tests actually showed that the stock paper filter was extremely well designed and flowed at least as good as a K&N filter, and the stock paper unit actually cleaned the air better. The paper filter's flow rate dropped off quicker as it got clogged, but that can be remedied by regular replacement of the filter. I don't know how the Z's stock filter unit compares to a K&N, though.

2) When replacing the intake tube with an aftermarket unit, people are often tempted to use metal pipes because they look good. However, tests around here have shown that the metal intake tubes do increase intake air temps since the metal more quickly transfer heat than plastic does. The Z's engine bay gets very hot, so that's an issue. If you use a metal tube, you might want to consider wrapping it with some sort of insulative wrap. Those same tests actually showed a significant reduction in intake air temps after insulating the metal tubes. Heck, I'd wrap a plastic tube, too. Looks ugly, but works well.

koihoshi

My own $.02.. I'm helping a friend with his car. But my own opinion on CAI is that horsepower is horsepower, even though the horsepower is a very minimal gain, the throttle response, little bit of better mileage and the small gain in horsepower is still a gain. You can do all the large modifications in the engine, modify the exhaust, do the headers, suspension, etc but still a gain is a gain in performance. Even if it isn't a huge gain, every little bit counts and if someone wants to do it, let them, there shouldn't be a problem with intake. Some people just have a problem with "stock" anything and can't wait to get something better, even if it's minimal, the difference to them is what matters.

Anyway, i just wanted to check out this thread my friend was talking about, doubt i'll be posting again. So anyway, take care of your rides and enjoy it all. Later!