Is it really worth putting a Cold Air Intake on 370z and what HP gains

Originally Posted by gsxr750

On to the question, do you really think the cold air intakes are really worth the money and do you really get real world HP gains.

One thing a lot of ppl. don't know about these external air filter systems is that while they do flow more air they also tend to let more dirt into your engine. I come from a sport bike background and early sports cars for 30yrs.

What we found out about oiled air filters is that while they may work good when new, after about a year of use on the vehicle they became very dirty and when we cleaned them, we were never able to get them completely clean. What we found was that there was a lot of dirt or grit inside the air filter and we were never able to get rid of it.

If we reinstalled the oiled air filter this dirt would have been sucked directly into the engine. Note we correctly cleaned it from the inside out, as not to allow any dirt into the inside of the air filter.

To play it safe we went back to a stock disposable paper airfilter element.

What a lot of ppl. forget is that the airfilter is meant to protect the engine from dirt and its best to install a new airfilter every few thousands of miles.

Another interesting note is that the use of external air filters style on sport bikes were abandoned, about 15yrs. ago after it was found that they really didn't provide any real hp gains over use of the stock air box and filter.

This was due to the fact that big 4 jap bike manufactures put so much design effort into the tunned intake air tracks on most sport bikes, that most after market air filters actually reduced HP when used.

While a lot of ppl still buy these external and internal oiled filter types on sport bikes, they do so because they really don't know how they work in real life driving environment.