K&N Cold Air Intake on '08 Ram 3500 w/6.7 Cummins

[daveinaz]

I recently put a K&N cold air intake system on our 2008 Dodge 3500 with the 6.7 Cummins in it. Just puttering around the neighborhood, I didn't really notice much difference. But over the weekend, I went for a little trip (not pulling the 5er) and accelerated like I usually do on the entrance ramp to the freeway. Before I got to the end of the ramp, about 100 feet before I could get over into the lane, I glanced down and was surprised to see that I was already going just over 75 mph!


Then I pulled the 5er around up to 55 mph and it seemed to have improvement there as well.

I don't know if the system actually gives the extra 20.63 hp or 43.35 lbs of torque, but judging by the highly scientific "seat of my pants" method, it does seem to be an improvement.

It was a pretty simple install.

[66joej]

That is interesting. Always thought from my souping up engine days the theory was "more air in needs more exhaust out" to get more power.

[daveinaz]

Originally Posted by 66joej

That is interesting. Always thought from my souping up engine days the theory was "more air in needs more exhaust out".

I know what you say was true back in the 70's when I was doing stuff like that on motorcycles. I don't know. You transfer the air intake sensors from the factory system to the K&N system, so I don't know if that makes a difference. Or maybe it just lets the turbo work better?

Who knows. Maybe the performance boost is all in my mind -- but it does sound a little better!

[Ken / Claudia]

Different trucks, but my results. 96 7.3 I got a bigger down pipe from turbo to under vehicle cost 200. Made to increase mpg/hp. Really not much noted except a louder exhaust, louder inside cab also. I ran that for a month or so than added the K&N cold intake around 400 if I remember right. No real noted difference, maybe if I put it on a tester before and after there was some gain.
This truck I have had the cold air intake on it maybe since 2004. Not really noted any difference.
I think better air flow is good but I am not making any vehicle exhaust louder again. I think I out grew that at 21.
No matter how good the sales pitch is on aftermarket bolt ons. I like to weigh the cost and pay back time for using those. My 96 was a waste of money on my part. This truck may have gained enough thru time to do better.

[rhagfo]

Maybe it feels better, because it cost so much. Oiled air filters are bad beans on a diesel. They may let more air in because they filter less. I would suggest getting a large paper element (AKA BHAF).

https://www.amazon.com/Cummins-Upgra...haf+air+filter

[daveinaz]

Originally Posted by rhagfo

Maybe it feels better, because it cost so much. Oiled air filters are bad beans on a diesel. They may let more air in because they filter less. I would suggest getting a large paper element (AKA BHAF).

https://www.amazon.com/Cummins-Upgra...haf+air+filter

Again, it's not an oiled air filter...

[Old Mustanger]

Originally Posted by 66joej

That is interesting. Always thought from my souping up engine days the theory was "more air in needs more exhaust out" to get more power.

The cold air kits don't necessarily provide more air, the idea for most of them is to provide cooler air by relocating the air filter to an area that does not receive as much engine heated air (as in moving the filter from the engine compartment to the wheel well). Cooler air is denser so the increase in power.

[mtofell]

Originally Posted by Old Mustanger

The cold air kits don't necessarily provide more air, the idea for most of them is to provide cooler air by relocating the air filter to an area that does not receive as much engine heated air (as in moving the filter from the engine compartment to the wheel well). Cooler air is denser so the increase in power.

From a physics standpoint this is pure snake oil. So, does a truck all of the sudden accelerate quicker on a 40 degree day versus an 80 degree day? Does it accelerate quicker first thing in the morning before the engine gets hot? I've never noticed any difference driving my trucks from temps in the teens to temps over 100. I stopped paying attention to K/N filters years ago after reading some pretty comprehensive studies totally de-bunking their effectiveness (not to mention all of the potential damage with CELs and whatnot). If what it's come to is saying the benefit is cooler intake air, it's laughable.

I'm really not trying to be a downer but I just can't resist pointing out the ridiculousness of this particular argument by the manufacturer.

[sourdough]

As I watch the thread progress I just have to add/say:....

I've added 2 aftermarket cold air intake systems in my life....what a waste. The 2nd was with all the "stuff" to increase "outflow". Increased airflow, new exhaust, chip etc. Never in my life have I spent so much, expected so much and received so little....except NOISE! Today's modern, computer controlled fuel injected engines won't give you some magic increase in power with a cold air intake. Good sales ploy but not proven out by science IMO.

[Old Mustanger]

Originally Posted by mtofell

From a physics standpoint this is pure snake oil. So, does a truck all of the sudden accelerate quicker on a 40 degree day versus an 80 degree day? Does it accelerate quicker first thing in the morning before the engine gets hot? I've never noticed any difference driving my trucks from temps in the teens to temps over 100. I stopped paying attention to K/N filters years ago after reading some pretty comprehensive studies totally de-bunking their effectiveness (not to mention all of the potential damage with CELs and whatnot). If what it's come to is saying the benefit is cooler intake air, it's laughable.

I'm really not trying to be a downer but I just can't resist pointing out the ridiculousness of this particular argument by the manufacturer.

Didn't say they do what is advertised, just what the idea is, but I'd swear that on every 'Stang that I installed one on it made a difference. YMMV

[JRTJH]

Polaris Slingshot SEL models have a "specialized cold air intake"
Polaris Slingshot SL models have a "standard air intake"

The factory specs on both are exactly the same HP and torque.

The engine is a 2.4l GM 4 cylinder automotive engine. If there was "something more than talking points" to cold air intakes, I'd guess that Polaris would "talk up the improvement in performance" but they list the specs as the same for both models.

Makes me wonder about cold vs ambient vs underhood air temperature and if there's any difference in burning it in a fuel mixture in a high compression engine that "explodes the fuel/air mixture without a spark.... It's more a matter of how much air the "hot turbo vanes" can push into the engine cylinders before the valves close and detonation occurs. With an intercooler to "chill the air mixture" I wonder what a cold air intake adds to the mix ???

[lunge motorsport]

So...
A cold air intake on a engine with an exhaust driven compressor? Hmmmm.
Ok, I too ran a K&N cold air system on a small block Chevy with an aftermarket exhaust that made nice noise but didn’t do much that I could tell. It was an oiled filter that claimed the dirtier it got the better it worked. That just made me reconsider the effectiveness of the media when clean.
I won’t do it again on a street motor.

[Don_T]

I have tried both dry and wet aftermarket cold air intake systems over the years. I think they are a waste of money. I have also read that until you get over 600 HP the stock intake system works as well as the aftermarket systems.

[travelin texans]

Originally Posted by sourdough

As I watch the thread progress I just have to add/say:....

I've added 2 aftermarket cold air intake systems in my life....what a waste. The 2nd was with all the "stuff" to increase "outflow". Increased airflow, new exhaust, chip etc. Never in my life have I spent so much, expected so much and received so little....except NOISE! Today's modern, computer controlled fuel injected engines won't give you some magic increase in power with a cold air intake. Good sales ploy but not proven out by science IMO.

I've done the very same! But 20+ years ago it was cool, sounded good, rolled lots of coal, but as far as more hp/torque or better fuel economy, I never realized either. All the expensive add-ons may have increased the mileage 1-2 mpg so in 50 years or a million miles they might have paid for themselves.
Nowadays the new diesels have as much or more hp/torque than most of us would ever need along with decent mileage & will most likely increase every year with the big 3 "mines bigger" mentality.
If you want to add on cool things to your truck then have fun, but don't expect miracles in power or mileage, it's just for fun. And remember some of those add ons may void any warranty you may have.

[daveinaz]

Wow. This turned into being just as opinionated as a "best oil" or "what tire brand" thread. LOL.

I don't really care one way or the other. I just threw it out there as my experience. Never expected such intense reactions.

Ya'll have a good day.

[Ken / Claudia]

There is a difference in an opinion and experience. I gained from what you said and if you read my post you should have gained some knowledge from my experience. None of which is bad it is just different.

[daveinaz]

Originally Posted by Ken / Claudia

There is a difference in an opinion and experience. I gained from what you said and if you read my post you should have gained some knowledge from my experience. None of which is bad it is just different.

I agree. You posted your experience. Others posted their opinion.

[chuckster57]

I do have a K&N filter on my ‘94 turbo IDI and my 2004 Honda Accord. Does the filter improve performance? I can’t say because I did a bunch of upgrades at the same time. I know someone that has a K&N on his 2002 F250 7.3 PSD. He drove in dusty conditions for 3+ yrs without servicing his filter. When I did some work on it we cleaned and oiled it as directed. He called and said his truck suddenly had more power, and I personally looked at the turbo for any sign of “dusting” and found nothing.

That’s about as real as I can make it. To each their own, but if you feel it made a difference then by George it did!!

I agree these threads can get into best oil, additive, brand of truck, etc....thank you for posting YOUR experience.

[ChuckS]

It’s an option some think is great. I’ve kept mine stock. I don’t have issues with foiled MAP or MAG sensors from oil residue getting on the sensors.

For me the $300 for the cold air kit goes a long way for tranny fluid and filter, fuel filter, new differential and transfer case lube, etc.

I’ve not missed the advertised 20hp increase.

But it looks nice

https://www.knfilters.com/mobile/col...-intake-system

[sourdough]

Originally Posted by daveinaz

I agree. You posted your experience. Others posted their opinion.

Many in the thread posted their personal experiences; a few posted opinions. Either way, I don't think anyone has been "out of line", irate or ugly. Because many didn't experience your "seat of the pants" feeling of improvement doesn't mean they are attacking you - just relaying their experience. If you believe your changes netted you an improvement, real or imagined (seat of the pants vs measured), you got your money's worth it would seem and I hope you continue to realize improvement from your mods.