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Just upgraded my 09 XF SC with 2 K&N drop ins and was wondering if I should have "altered" my air boxes for better flow and or better sound if so how? Thanks for any and all replies.
Nope, just drop them in and clean them every 20kmi or so. Plenty will say they are not an upgrade but I've been to a few K&N open houses (They are HQ here in Riverside CA) complete with vistor dyno runs including my own run that showed a 8hp gain on my 1999 Z28, not much but dam cheap hp. We also use them on our many 30 hp vacuum blowers at my job as they are servicable and tough.
I've never had issues with my K&N drop in filters. Make sure they aren't over oiled and you will be fine. If you over oil them it can cause issues with the MAF sensors.
I use them on my STR and have had no problems, think it slightly increased induction growl. It reduces vacuum and therefore increases airflow into the supercharger. Everyone knows positive displacement superchargers are very sensitive to inlet restrictions so I'd say it's an upgrade. I agree I wouldn't bother on a N/A car. Probably only worth a few HP at stock boost over a paper filter but cheap hp nonetheless.
I use them on my STR and have had no problems, think it slightly increased induction growl. It reduces vacuum and therefore increases airflow into the supercharger. Everyone knows positive displacement superchargers are very sensitive to inlet restrictions so I'd say it's an upgrade. I agree I wouldn't bother on a N/A car. Probably only worth a few HP at stock boost over a paper filter but cheap hp nonetheless.
The increased intake noise combined with not having to buy new ones each time is enough for me. Might have gained hp as well, so that's just a bonus. Never had an issue with filter oil getting where it shouldn't and I've been running K&N in almost every vehicle I've had for over 20 years.
I have been running k and n drop ins for nearly a year!! No probs whatsoever.
I've heavily opened/cut away the lower part of the airbox and smoothed out the intake pipe by removing the silencers.......running quick silver rear boxes and no center silencers/resonators. Its been on a well known mustang dyno used for Jaguar tuning and makes way more power than a standard R.....
What is the benefit to cutting away the lower part of the air box. Do you think there was some restriction in there. Do you have any pictures of what you modified?
I agree on being careful about cutting up the airboxes as you begin to lose the factory cold air system. This would increase heat soak and you'd then lose the power you gained from less vacuum to higher IATs. Every 10° increase in intake temps equates to around a 1% loss of power on supercharged cars. The only way to improve on the K&N panel filters would be to design a true cold air intake system with cone filters isolated from engine bay heat e.g. in fender wells. Not really worth it unless you did some serious mods.
Agreed........its fruitless hacking away at the engine side although tbh the heat soak from the black intake box is not great anyway.......the portion of the airbox I cut away is on the outside face of the wings and the front portion by the headlights......theres even a nice large hole to the cavity behind the front bumper that I exploited when drilling the boxes........bonus extra cool air......
Agreed........its fruitless hacking away at the engine side although tbh the heat soak from the black intake box is not great anyway.......the portion of the airbox I cut away is on the outside face of the wings and the front portion by the headlights......theres even a nice large hole to the cavity behind the front bumper that I exploited when drilling the boxes........bonus extra cool air......
any pictures on this?
Sorry, newbie here. I just recently did the K&N drop in filters. who can say no to more cool air.
I have played around with making lower boxes that are open because I want to keep the stock boxes encase I want to go back to stock or during the hot 3 months we have here.
Here is what I came up with.
Still uses the factory cold air piping and the new aluminum end acts as a heat sheild.
Even with the stock paper elements, the blower screams...
Agreed........its fruitless hacking away at the engine side although tbh the heat soak from the black intake box is not great anyway.......the portion of the airbox I cut away is on the outside face of the wings and the front portion by the headlights......theres even a nice large hole to the cavity behind the front bumper that I exploited when drilling the boxes........bonus extra cool air......
How large were your openings? Did you run any ducting to the airbox to direct the air?
K&N Drop ins Question
