XKR Airfilter
Does K&N make a Factory type Cartridge Filter or should I get the Cone Shaped Filter and remove the Airbox? I'm going to upgrade the Exhaust at some point, too. Any suggestions. Cheers.
Hello, do not bother to remove the original air filter box from your car.
The original air cleaner filter is designed to bring the cleanest, coolest air to your engine.
I know the other seems good and they say it raises horsepower, but the point is to bring cool clean air to your engine .
Think about it, if you use a straight cone type filter, it is bringing in the hot air from the engine compartment to your throttle body, that is the worst scenario you can get.
Where does the engine get cool air? Hot air is detrimental to MPG, Horsepower and general engine well being.
Just my thoughts and experience. Cool clean air is the absolute best thing to your engine, that could happen.
Not clean hot air from,
A NEW CONE STYLE AIR FILTER THAT DRAWS AIR FROM THE ENGINE COMPARTMENT THAT IS HEATED FROM THE ENGINE!! iT MIGHT LOOK NICE, BUT IS NOT RIGHT FOR YOUR ENGINE.
For what it's worth,
HAPPY MOTORING...
The original air cleaner filter is designed to bring the cleanest, coolest air to your engine.
I know the other seems good and they say it raises horsepower, but the point is to bring cool clean air to your engine .
Think about it, if you use a straight cone type filter, it is bringing in the hot air from the engine compartment to your throttle body, that is the worst scenario you can get.
Where does the engine get cool air? Hot air is detrimental to MPG, Horsepower and general engine well being.
Just my thoughts and experience. Cool clean air is the absolute best thing to your engine, that could happen.
Not clean hot air from,
A NEW CONE STYLE AIR FILTER THAT DRAWS AIR FROM THE ENGINE COMPARTMENT THAT IS HEATED FROM THE ENGINE!! iT MIGHT LOOK NICE, BUT IS NOT RIGHT FOR YOUR ENGINE.
For what it's worth,
HAPPY MOTORING...
K&N does sell a drop in filter--I bought one almost immediately after buying the car. I can find the part number for you if you need it but I recall that I did not have any trouble ordering it on line from somewhere (Amazon?).
Doug
Doug
+1 on this answer.
Note that the OEM airbox has an intake from the front of the car to pull its air supply. Air does NOT come from the engine bay. Check to make sure this is connected. Easy to leave off when changing the filter and it will slide into the fender well out of sight.
Note that the OEM airbox has an intake from the front of the car to pull its air supply. Air does NOT come from the engine bay. Check to make sure this is connected. Easy to leave off when changing the filter and it will slide into the fender well out of sight.
I got rid of my cone filter that the car had put on by a previous owner. I put a factory air box back into the Jag with a K&N panel filter inside and improved the power (no hot air coming in)... then I took it a step further. Consider doing THIS: https://www.jaguarforums.com/forum/x...r-boxes-76906/
Messing with the air filter is not going to give you any usable power increase. If you want power in an old high performance car, give it a real tune up as most cars this age are down on power at least 20% due to worn sensors and management parts. Change all plugs and filters, switch to synthetic lubes everywhere, get the injectors cleaned and matched, change the MAF and O2 sensors . You will get way more power than with exhausts and air filters and the car will last longer and run better.
Trending Topics
I also made the change to a baffle cone installation, it was a waste of money and a big loss in power. Went back to the stock box and the K&N panel filter. No regrets. Be careful about over oiling the filter, the off gassing oils can foul the mass air sensor.
Mendo,
Consider this: With the supercharger, your engine's not "inhaling" air like a normal engine. It's being RAMMED into the engine, so adding a free-flow component isn't going to effect the supercharger's ability to do this by much. As for "cooler" air - the others are right: you'd be inhaling engine compartment air vs. the cooler air from the OEM set-up. And also consider that we use "radiator" coolant (already mighty hot) for our heat exchangers, so how much difference could a a few degrees of ambient possibly make?
CORRECTION: After I wrote that inter-cooler piece (which always did seem questionable) I checked out the system in detail and realized I was wrong (quite embarrassingly too!). PLEASE DISREGARD. (oops)
This is the most complicated and advanced engine I've ever work with (out of maybe 10 others I've modified). I can't see too many justifications to wonder very far from spec unless your talking about increasing boost to go with the new exhaust.
Hmmm,... Being as I already have the free flow exhaust - - Now THAT's an interesting idea!
We're ALL masochists, you know - right?!
Consider this: With the supercharger, your engine's not "inhaling" air like a normal engine. It's being RAMMED into the engine, so adding a free-flow component isn't going to effect the supercharger's ability to do this by much. As for "cooler" air - the others are right: you'd be inhaling engine compartment air vs. the cooler air from the OEM set-up. And also consider that we use "radiator" coolant (already mighty hot) for our heat exchangers, so how much difference could a a few degrees of ambient possibly make?
CORRECTION: After I wrote that inter-cooler piece (which always did seem questionable) I checked out the system in detail and realized I was wrong (quite embarrassingly too!). PLEASE DISREGARD. (oops)
This is the most complicated and advanced engine I've ever work with (out of maybe 10 others I've modified). I can't see too many justifications to wonder very far from spec unless your talking about increasing boost to go with the new exhaust.
Hmmm,... Being as I already have the free flow exhaust - - Now THAT's an interesting idea!
We're ALL masochists, you know - right?!
Last edited by scardini1; Sep 9, 2012 at 07:35 PM. Reason: Mistaken System Understanding
Just to add my 2 cents worth, I also had the K&N cone filter in and really felt a loss of power. It also increased supercharger sound to the cabin that I really disliked. I prefer the growl I get from my MagnaFlow exhaust system. I agree, the cooler air from the front fender is the better option. K&N Kit for sale... !
K&N is complete rubbish, great way of ruining a high tolerance engine.
Manufacturers desperate for every ounce of HP are not stupid, they can make their filters with cotton- the reason they dont is because engine longevity is more important to them, and it should be to you too.
K&N is great for hillbilly motoring, where the engine is rebuilt more often then new tires purchased.
Here is empirical data that will make you throw them out immediately. K&N Air Filter Review - Debunking the Myths (and why OEM is better)
Manufacturers desperate for every ounce of HP are not stupid, they can make their filters with cotton- the reason they dont is because engine longevity is more important to them, and it should be to you too.
K&N is great for hillbilly motoring, where the engine is rebuilt more often then new tires purchased.
Here is empirical data that will make you throw them out immediately. K&N Air Filter Review - Debunking the Myths (and why OEM is better)
K&N is complete rubbish, great way of ruining a high tolerance engine.
Manufacturers desperate for every ounce of HP are not stupid, they can make their filters with cotton- the reason they dont is because engine longevity is more important to them, and it should be to you too.
K&N is great for hillbilly motoring, where the engine is rebuilt more often then new tires purchased.
Here is empirical data that will make you throw them out immediately. K&N Air Filter Review - Debunking the Myths (and why OEM is better)
Manufacturers desperate for every ounce of HP are not stupid, they can make their filters with cotton- the reason they dont is because engine longevity is more important to them, and it should be to you too.
K&N is great for hillbilly motoring, where the engine is rebuilt more often then new tires purchased.
Here is empirical data that will make you throw them out immediately. K&N Air Filter Review - Debunking the Myths (and why OEM is better)
+1 (On Gus comments of course)
My engines where still perfect after 120K, using only K&N filters and have driven them hard with lots of extra performance as well.
The test shows for one that you may need to clean you filter more often, especially when performance is the objective.
The stock paper filter is already in-adequate for the XKR (maybe ok for the XK8 as that one needs less air), and with a K&N panel filter you can already gain more power, especially once you start there to increase the airflow more by pulleys etc.
Here the test also clearly shows that you can at least gain 1” of vacuum (to amazingly much more for some paper filters, like the acdelco!), and I have seen about 1 to 1.5” difference in favour of the K&N panel filter compared to the stock one. Once tuning the difference only becomes larger, and thus you are losing more power.
My engines where still perfect after 120K, using only K&N filters and have driven them hard with lots of extra performance as well.
The test shows for one that you may need to clean you filter more often, especially when performance is the objective.
The stock paper filter is already in-adequate for the XKR (maybe ok for the XK8 as that one needs less air), and with a K&N panel filter you can already gain more power, especially once you start there to increase the airflow more by pulleys etc.
Here the test also clearly shows that you can at least gain 1” of vacuum (to amazingly much more for some paper filters, like the acdelco!), and I have seen about 1 to 1.5” difference in favour of the K&N panel filter compared to the stock one. Once tuning the difference only becomes larger, and thus you are losing more power.
Last edited by avos; Mar 28, 2015 at 01:25 AM.
Avos, have you checked differences in vacuum between K&N panel and 'open' cone setup (simota, pipercross, etc)?
Main disadvantage of using non OEM 'tuning' filters is poor air quality they deliver to MAF/supercharger/engine. I don't think it's worth 5bhp gain.
Main disadvantage of using non OEM 'tuning' filters is poor air quality they deliver to MAF/supercharger/engine. I don't think it's worth 5bhp gain.
The power difference becomes bigger the more air you are sucking in (so if you play with pulleys or iirc like you are making a TS setup).
I even think the power difference for a stock XKR engine could already be more than 5hp, somewhere between 5 and 10 I would think. Cheapest hp per $ you can get here.
As the filter (and intake) setup isn’t properly designed for performance even for a stock engine, the limitations only become bigger when you tune the engine. It is not just lost air that is holding power down, the vacuum is also consuming power from the supercharger to run, this all adds up. You need proper sizing of the filter to keep the vacuum as small as possible that is key here.
I have made my intake now such that with the airflow I have (>50% over stock), the intake vacuum is only 20-25 mbar at wot. Of course this is with a very large K&N cone filter. Oversized so I don't have to clean it that often as well ;-).
Am not aware of any issues with the K&N panel filter, and I have used it for some time (guess about 80Kmiles or so).
Where it could go wrong is when people start to play with cone filters and the MAF itself (ie some Mina filter setups for example), this is something you have to be careful with, as altering the flow of the air past the MAF has an effect on its readings.







