Any disadvantages to using a k&n filter on LT1?

A couple of people on another forum have said that k&n filters let through more dirt, and are actually bad for the engine.

Just wondering what you guys think. I just put in the 33-2057 filter (fits right into the standard air box) 2 days ago. I thought I noticed a little more pep, and it seems to shift easier (quicker) with less pedal.

They seemed to have some good points.

I have a 94 RMW with LT1 and 85K miles.

Thanks for any advice.

What air pressure drop did you measure across the filter with the stock filter vs. the K&N? I'll bet you an optispark that there is no measurable difference on a stock vehicle other than at WOT at redline.

You have to clean the K&N filter, and the time is not worth the effort. I have one if you want it for $15 shipped. You will have to buy the cleaner, and oil.

You should go ahead and do the "hockey puck" mod as well.

Back in the day I had a K&N filter. I swiss-cheesed the front of the airbox too to get more air inside. Seemed to give me more zip...but I prob just made it up in my head since the engine was louder @ WOT (since I got rid of the silencer boxes)

I trimmed the bottom of the home plate where it went into the TB elbow so it still fit with the hockey puck installed. I liked the look of the home plate ontop.


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Later I did the HomeDepot pipe version...

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There may be a link between using a K&N style filter and MAF failure. Independent tests suggest oiled filters may not filter as well as paper filters, yet deliver little increase in air flow -- oiled foam and cotton filters do indeed have better air flow per square inch of media, but traditional pleated paper filters have much more surface area, so overall airflow is equivalent.

Finally, I have seen tests that show the filtering capability of oiled filters, particularly oiled cotton filters, degrades in far less time than K&N's longevity claims. These filters rely on dust sticking to the oily surface. As dust coats the surface, additional dust passes right on by. By comparison, filtration provided by traditional paper filters actually improves as the filter clogs with dirt (although airflow deteriorates inversely).

I do use K&N filters in certain applications where a reusable filter is particularly desired. Certain Japanese motorcycle manufacturers are famous for charging outrageous prices, then ceasing production after a few years. When the choice is paying $100 for a disposable paper filter vs $75 for a resuable one or when the OEM changes designs every 2 years and refuses to support their previous models, a reusable filter is highly desirable.

However, I have the following caveats:
1. I never use an oiled filter on a vehicle with a MAF sensor.
2. I clean and re-oil the air filter twice as often as I change the engine oil.

But that's just my 2¢.

Good information, although I'd still like to hear more from others that have tried the k&n. I think I'm leaning towards going back to the paper filter. Is there a preferred manufacturer for the paper filter?

Also, I live in Florida, where it rains a lot and its usually very humid. Compared to other drier places, i suspect there may be less dust in the air. Probably a lot more pollen, spores and junk like that, but I don't really think there is a lot dust. The rain is always knocking it down.

Could this be a factor in determining which filter type to use?

Thanks again.

I have a K&N set up with the pipe (vs a filter in the stock airbox). I put it on my 94 RMW before a trip to Ralieigh from South FL. (850 miles one way). I ran the setup up and back to Jacksonville two weeks before the trip and the car definitely felt peppier at highway speeds when I got on it (WOT) to pass. What I noticed was 2.5-3 MPG DROP in fuel economy.

At first on the JAX run (325 miles each way) I thought it was my heavy right foot. But then on the longer Raleigh drive, I stayed out of it as it was a long cruise. Once in Raleigh I swapped back to the stock set up and got my 2.5-3 MPG back for the ride home. Some folks said it was because FL was downhill, but that's BS as the majority of the trip (and several tanks of gas) where in the flatlands of eastern GA and FL and Raliegh is only 300 ft above sea level .

If I were just sticking with the stock setup...a paper filter is all I would run (which is what I have in the Fleetwood I use as my DD).

I have an oil free (but washable and reusable) cone filter in my RMW. They do not make a version for a stock airbox.

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Chris

ps. That K&N filter I bought in 2003? I used it for about 6 months then gave it to my Dad who still has it in his DD RMW. No MAF failure for him.

Ten years of a K&N on my SS. Still running, still fast, still getting good mileage. I clean the filter every few years.

K&N and MAF can be a fatal combination for your transmission if not used correctly. An over-oiled* filter will contaminate the MAF hotwire element and cause the MAF to underestimate airflow. This is reported to the ECM/PCM, this information is used to help determine engine load. Transmission line pressure is then adjusted according to this load. Now, if airflow is under-reported, the ECM/PCM sees this as less load and drops line pressure according what it (ECM/PCM) knows, when in fact the load can be much higher and if it is, line pressure should be much higher than what is being requested. The result can be transmission overheating followed by slipping.

*The over-oiled condition of the filter is usually the result of incorrectly cleaning and re-oiling of the filter. Proceed at your own risk, in my opinion.