Northstar Engines and System Technical Discussion Discussion, K&N Filter On Caddy? in Cadillac Engine Discussion; Anybody have experience/results of adding a K&N air filter to their Northstar? If so, please share!...
I have one on my Fleetwood and love it. As far as I know, K&N does not offer a Fuel Injection Performance Kit for Cadillacs. A quick check at their website will confirm this. You CAN however still use the main part of the kit, the cone filter. The problem is, you're on your own as to how to plumb it into the intake. Most guys I know use simple PVC piping from Home Depot and rubber sleeves/clamps. Either way, you will notice a rather significant improvement in both performance, and MPG. Of course, to get the most increase, you'll need to modify the exhaust as well to increase flow. Just remember that an engine is just a big air pump, and if you increase the engines ability to GET air, you've got to increase it's ability to EXHAUST the air.
Note, these are MY experiences -- yours may vary. Most of the K&N "kick" is perceived because of the loud roar produced by the filter. You won't gain but maybe 2-3 horsepower by adding one.
Want to prove it to yourself? Install a vacuum gauge in the intake tract, between the throttle body and the filter. Run the engine at varying speeds, WOT, idle, etc. You will probably NEVER see a vacuum. I tried it and never saw a vacuum on mine. This means that your engine is NEVER pulling more air than the stock tubing and paper filter can provide.
Even if you DO see a slight vacuum sometimes, it's certainly not constant, and you'll certainly rarely see the benefits of a K&N filter on the average street car. Plus, you run the risk of over-oiling them and contaminating your MAF sensor.
Sorry you went through so much work and ended up unsatisfied. I would say you did a good job on the install overall. Your assertions about the vacuum gauge in the intake tract might seem to be valid but in truth you'll find that in order to see a reading on a standard over-the-counter vacuum gauge, you'd have to have a rather substantial restriction. The fact that you said you had better high RPM performance would indicate that you were obtaining better flow from the K&N filter. As for the better low-speed throttle responce you said you got with the OEM assembly, I would say that POSSIBLY you should've reset the PCM so that the short-term block learning curve would've been a little quicker for you. In other words, it's possible that the PCM would've adjusted to the new filter if given time. Who knows?
I must admit, you're the first person that actually had any performance decreases after installing a less-restrictive filter.
I believe the upper RPM gains were at least half perception -- just because of the noise. I believe the car pulls just as hard with the proper filter in there. Even given any upper end gains, the lower end disappointments were not worth it.
I also believe heat was a factor. Even though I built a heat shield for the filter, I think it was still pulling hot air. Similar results are posted at www.caddyinfo.com -- loss of performance with a cone filter.
Another factor is the "stockness" of the rest of my vehicle. Everything is showroom stock on the car, with no modifications whatsoever. If I had performance mufflers on the car, I may have seen different results. But I don't want performance mufflers on it -- "silent but violent" is my motto.
It still G-techs at 6.7-6.9 seconds 0-60 -- that's well ahead of most imports, stock and modified. Also, many older Mustang and Camaro owners would be surprised. I ran dead-even with a SC3800 GTP one time (and they're supposed to be 6.7 0-60).
(In a nutshell, I'm happy with the performance of the car and don't wish to modify it any further; thus, keeping the cone filter wasn't worth the compromise to me.)
With me, and my car, even if it didn't net me anything, I STILL would've done it for the intake roar. Gotta LOVE that small block. Add to that, the 3-chamber FlowMasters at full throttle and all I can say is my pants get tight dude! And God what looks you get from the guy you just went by
Get me around anything with an engine and I go right back to being a kid, I just can't help it.
I'm sure there's a reason that paper filters are by far the most common out there -- and why many trucking companies and construction firms don't use K&N and other "high performance" filters. There's usually an inverse correlation between flow and filtering. You can look right through a K&N filter -- the filter media is so loose, you can see through it. The oil is supposed to catch everything, but that oil is also getting into your throttle body and MAF sensor, etc. Yuck. People have fouled their MAF sensors with K&Ns. Luckily, I haven't heard of a Caddy guy doing that, but maybe it's a matter of time?
Here's a REAL test of differing filters, rather than the advertising claims that they make:
That guy is obviously an Amsoil fan, but unless he flat-out lied about his numbers, I think they're probably about right. I've heard similar stories from other people. And his results seem to match my experience -- the K&N produces no real speakable gains in performance -- and probably passes more dirt to your engine in the process.
Any filter that reduces restiction to airflow WILL give you an increase in performance to a point. As long as the filter is able to match the maximum flow of the engine, I don't care what media it's made of.
The comment about how you can see through the filter and that the oil is supposed to catch the dirt, and that you then get oil in the intake and sensors etc. is a little mis-leading. The reason is this; Oil-bathed filters ARE the best, and always have been. Matter of fact, they've been around for years (I think they were actually the first filters used in cars). The problem is that they require some maintenance, and that doesn't fit in with our throw-away society. People just want to pull out the old one and throw in the new one. Unfortunately, oil-bathed filters are a little more work than that. But if they are serviced CORRECTLY, they will do a superior job. I've seen guys buying K&N filters and improperly oiling them, improperly cleaning them, etc. and I think THAT'S why they have problems.
And there ARE many copy-cat cone filters that do not do a good job and they are helping to give ALL cone filters a bad name.
In MOST cases, the OEM air filter does a fine job, but will provide a degree of airflow restriction. That's why GENERALLY a K&N replacement filter (and to a greater degree, the cone filter), will provide a SLIGHT power increase. Maybe it's only a couple HP, maybe it's more. But anytime I can get a couple HP by just changing a filter, I'm gonna do it. HP is too hard to find, and it gets rather expensive. If you don't intend to do any mods to your car, the drop-in filter will do just fine. But if you intend to do any mods to either the exhaust, or intake, you should go for the cone filter.
Originally posted by jadcock I'm sure there's a reason that paper filters are by far the most common out there -- and why many trucking companies and construction firms don't use K&N and other "high performance" filters.
filters for the big Donaldson and Vortox air clearners can cost upwards of $250 EACH but also last almost as long as most High performance filters because you just dont throw away a $250 filter every oil change. Most drivers simpley blow the dust out of them when ever they start noticing a loss of power or whe the filter restriction guage lets you know. but you know? if K&N made a filter for my big truck if run em
My Caddy had the K&N filter in it when I got the car. Its a drop in filter and not the cone. I have cleaned it and oiled it as per the instructions on the package. I also still have the paper filter that was in the K&N box when I got the car. It is still clean, and I may try a comparison when I go to the track this spring to see if there is any difference. The car also has one of those Tornado air domaflitchies in it as well. I will try a run with and without the Tornado to see if there is any difference. Has anyone else had any experience with the Tornado? I read on the GMForum that its a piece of crap, but I'm no expert. Any thoughts on this would be great.
Katshot, I agree with you about the improper oiling issues. The fact that newer machines are much more sensitive to this brings this out. Back when you had a carburetor, it didn't matter how much oil you put on it. But with a very sensitive (and expensive) MAF sensor, extra oil can be an expensive endeavor.