Has anyone purchased a K&M air filter for their jag? How effective or good do they work? Is it worth it?

Thanks
James

 

No, but I hear that some folks have problems with the K&N filters due to oil from the filter contaminating the mass air flow meter.
Vector

 

K&N filters are a fine product and in there place are a very efficient. BUT IF you over oil them after cleaning the oil gets sucked in and.
1.-can mess up the sensor in the throttle body
2.-can mess up Mass air flow sensor
3.-can shorten the life of 02 sensor
4.- have been known to cause odd CELs.
They were intentionally made for older big block engines because of the free flow design and have low air restriction and upper end lube, but people have had good success them on jags on this forum so research before spending.

 

As billbjork says they are a quality product and if used properly can give you a couple of horsepower extra on the top end. The biggest mistake people make is cleaning them to often and as mentioned over oiling after cleanup. I have one on all my vehicles and have had no problems.

 

Noxparadise, I have been running a K&N filter in my car for the last 50K+ miles. No issues with the filter at all. I figure right about now I am breaking even with the filter as I don't have to buy a replacement paper filter. I simply clean my existing filter.

Like was mentioned, if you over oil the filter, you can have issues. But, you do as the instructions say, if not go slightly on the light side, you will not have any issues with the oil coming out of the filter and then going up the intake. Another quick check that you can do is to oil the filter and then rest the filter up on a corner so any oil that may leak out of the filter will go to that corner. If you get any oil out of the filter after an hour of being on the corner, then you over oiled the filter. Clean it again and oil less this time.

As for doing a better job than a paper filter, this is a big point of contention. What you need to ask is "how big of a particle will cause damage to the car"? Now, keep in mind that we are talking on the scale of thousandths of an inch. Items like a grain of sand and whatnot, both filters are going to stop 100% of that. When you are talking about something in the range of 0.001" or smaller, the paper filter is going to do a better job when it is new when compared to a freshly cleaned K&N filter. But, shortly after the two "new" filters are installed, the K&N will start collecting as much as the paper filter. Ironically, the K&N filter cleans the air better the longer you let it go between cleanings. Now, that is with the caveat that at some point, the amount of dirt in the filter is going to also start restricting the air flow.

If you are trying to maximize power by using a K&N filter, then this is the expensive way to do it. The gains in modern day engines from a filter like this is minimal. If you gain 1 hp and 1 ft-lb of torque, then you are doing pretty good.

So, in short, if you are planning on keeping the car for the long term, then getting a K&N filter is probably a money saving thing. If you know you are going to be getting rid of the car in less than 50K miles, stick with the paper filters.

 

Hmm sounds like a toss up, I've always thought about getting a K&N filter but wasnt sure of the benefits vs price. Well I do plan on keeping my car until it gives. I'm at 130700 it has an antifreeze leak plus when it's a bit cold outside when it starts the RPM drops really quickly to about 500 or less then revs back up to 1000. Dunno if this is a sign of anything just trying to keep my car running good.

 

As has been said...K&N is a quality product. I have been using them since my Porsche 911, in 1968, my Vette, Alfa, Jag, BMW twin cycle, Lexus, and Hyundai. At the least, they reduce the cost of filter changes every service. At best, some improvement...but it has been a matter of discourse for many threads...so you pays your money, and takes your choices...there are as many who (like me) swear by them, and just as many who swear at them..

 

I have a K&N Panel filter in my X, no running problems at all, no em lights, pulls noticeably harder after 3500 rpm.
Avoid induction kits/cone filters

 

Note: I have a sensitive, digital differential manometer (for aviation use) and it's handy for such testing.

I purchased a K+N airfilter last year. Bottom line: I am very pleased.

The first thing I did was to modify the 2 intake "snouts" by making a third opening. This dropped the pressure upstream of the filter by about 2-3 inches of water at 6000RPM. I did not notice any performance improvement, nor would I expect to.

I then installed the K+N airfilter. I did not test the pressure differential of the stock filter v the K+N, as my stock airfilter was quite old. And, there is no sense in testing a clogged filter. But the K+N has essentially 0 restriction and I did notice a small, but definite improvement in acceleration. In fact, with just these 2 little mods, the car is faster than it's been for all it's life. Wish I had done it sooner.

The i

 

One more thing, I've never had an engine wear out with a K+N. Nor has anybody else I've ever known.

It can be proven that the K+N does not trap fines as well as an OEM filter. OK, so what? Those tiny particulates are likely too small to create wear. In much the same way as an oil filter keeps particulates to a harmless size. The oil still gets black and is full of particulates, but none are large enough to do any harm.

 

Without measuring the restriction of a stock filter (if any) for comparison and without anything other than a subconsciously biased butt dyno, it's difficult to presume that anything has been gained.

An OEM air filter would have to be very poorly designed and maintained to actually cut into performance.

 

I use an old G-Tech. It shows consistent improvement in the rate of acceleration and a few MPH gain in trap speed. I can actually get over 90MPH trap speeds now.

Scientific testing, no. Did it help? Yes, and more than I would have thought.