Air filter conversion? Good or Bad??


Old 10-18-04, 07:37 AM
Visiting Guest
Posts: n/a
Air filter conversion? Good or Bad??

I have a '91 Jeep wrangler 5sp 4.0 6cyl. and I am interested in upgrading the air intake with a K&N oil/air filter kit. What I see from the instructions, I will have to take the old system out completely, and install the new kit to the engine. What I would like to get is several opinions on this type of air filter, and does anyone know if it is REALLY a better air filter system. I am switching to this system for two reasons...1. I am still getting some oil in the filter even after changing the ccv gromets & hoses (both front & back) and checked for vaccumn at the end of rear hose (which I get) but still get oil in the filter. 2. The new system is advertised to get better hp hence better fuel economy. Does it? Anyway, I hope I can get a few thoughts on adding this new system to my old jeep, as the new system is a bit pricey, I don't want to add it if it won't solve my issue. Thanks to all who answer.
Sponsored Links
Old 10-18-04, 07:53 AM
Join Date: Oct 2004
Location: Ontario
Posts: 539
i dont think it will solve your oil isue
as for the filter the only selling point i find is that thay are cleanable so you shouldent have to buy a new one but if it fills with oil from your engine than you wilbe cleaning it a lot
Old 10-18-04, 08:37 AM
Join Date: Aug 2003
Location: Cape Cod
Posts: 4,320

K&N does have just a replacement panel filter for your Jeep
They do flow air better than paper elements
This can free up HP
It can, on some systems, straighten out the airflow and free up more HP than running with no filter
You don't have to clean them often, some dirt actually seems to help
In fact you can clean them too often
If you are getting oil spots on your paper filters and having to dispose of them often, I could see wanting to switch over to a K&N filter
If you do any off-roading it's a good idea
And from a money standpoint, It's a good investment
You'd have to see some dyno runs with your engine to be sure, but from what I've seen on other FI engines, I'd be shocked if you didn't pick up some HP (3-5, maaayyybe 7-10)

It sounds like you mean one of their Fuel Injection Performance Kits
I have not tried one of these, but it looks like there goal is too eliminate the bottlenecks for airflow into the engines
On most FI vehicles there are many, so a system like this can free up HP and torque
This a a common hot rodding trick for FI engines and generally works
But, the FIPK is not the same for all engines
I have seen them relocate a "cool air intake" from the fender
And put a big conical filter in the engine bay near the fan
It looks really awesome and flows more air but, it's now warm engine bay air (warm=not good) and it's now in the fan wash (disturbing the smooth flow of air into the engine)
Can you post a link to a picture of what you were looking at for your Jeep?

-Just found the info
Looks like "Gen II" addresses these concerns
Same position as stock and a heat shield, nice

-Ate lunch then looked at the instructions I d-loaded
sicando, this kit relocates the crankcase vent to what looks like a foot or more from the filter!
You still might get some oil in the crankcase vent, but I can't see it getting on your filter with this setup (if some does it won't hurt it anyway)

Last edited by slickshift; 10-18-04 at 09:28 AM. Reason: adding more
Old 10-18-04, 03:25 PM
Visiting Guest
Posts: n/a
A big THANKS to all who replied! I think I will go with the panel type replacement by k&N to see if this helps with air flow. The amount I get in the paper filter caused by blowby frome engine is a lot smaller than when I had the clogged ccv grommet, but I think the washable/oil based k&n air filter panel filter that fits into my a/f housing is where I will start. Thanks again for all your input. I'll let you'all know my findings. Also much thanks to the techs who helped me decide on my tranny fluid change. I went with the synthetic (valvoline) for my trans. as well as both differentials and my jeep shifts better at this writing. I am thankful for all the advice I recieve at this site...sure helps when your not sure just what to do......Happy Motoring to all.

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Display Modes