So, I won a Ridgeline K&N CAI kit on eBay...

[BoilermakerFan]

Figured if I could score one cheap it enough I'd try it to see if it fits. One of the mechanics who has a MDX thought it might too, but wasn't willing to drop $300 on one...

So I scored it used off eBay for $130. I know the stock airbox is cold air. I didn't buy it to get the 10HP it claims from dyno testing. I did it so I can stuff a 6"x7" Volant PowerCore filter on it and I'll measure to see if I can fit an 8" diameter version in it to gain even more filter area.

And perhaps in the future I might even mod the hood above the intake with a small functioning hood scoop to really stuff the filter box with air on the highway.

I'll document the fit with pics of course. Either way.

[humanoid]

Sweet, can't wait for the pics!

[rocky]

Looked at K&N website and they publish this handy chart on HP and Torque differences before and after install.

http://www.knfilters.com/dynocharts/77-3515_dyno.pdf

[BoilermakerFan]

Yeah, I had looked at the graph earlier. Small bump along the power band, but I'm not really convinced it has as much to do with the pipe and mostly to do with the 2X increase in area of the filter area.

I don't think I'll see the full 10HP unless I can fit the 8" round x 7" long Volant in the box since it the 6" round filter may not flow as much air as the stock tapered cone K&N.

[LetsGo]

Originally Posted by BoilermakerFan

Yeah, I had looked at the graph earlier. Small bump along the power band, but I'm not really convinced it has as much to do with the pipe and mostly to do with the 2X increase in area of the filter area.

The biggest restriction in the intake system is the throttle blade. OK, so at wide open throttle, you should be pulling max air, right? But at low RPM, it's not pulling as much air as at high RPM, so any restriction should show increasingly as you approach high RPM, full-throttle operation. But their graph is close to linear with an advantage showing even at low RPM. If the engine pulls more air as RPMs increase and the filter is the restriction, shouldn't it show more gains at the higher end of the RPM range?

[BoilermakerFan]

Originally Posted by LetsGo

The biggest restriction in the intake system is the throttle blade. OK, so at wide open throttle, you should be pulling max air, right? But at low RPM, it's not pulling as much air as at high RPM, so any restriction should show increasingly as you approach high RPM, full-throttle operation. But their graph is close to linear with an advantage showing even at low RPM. If the engine pulls more air as RPMs increase and the filter is the restriction, shouldn't it show more gains at the higher end of the RPM range?

I think the graph quality is lacking resolution, but the horsepower gain is greater at the upper RPMs than lower in the revs. That was with a stock exhaust too, so I wonder what my curve would do if I had access to a AWD dyno.

EDIT: Good news is that it's scheduled to arrive Monday.

[N_Jay]

All the gains will come from the increase in sound.

The 10 or even 20 extra HP that only come in at the upper end of the revs and only under full throttle are mostly meaningless.

[BoilermakerFan]

We all know your opinion on higher flow air filters and exhausts Jay since it shows up in every thread that comes up in the search results, as well as your belief that they do nothing to add power or improve fuel economy. If you feel 20 extra HP at the wheels is meaningless, that's your opinion or belief, but you don't need to piss in every single thread that discusses them.

I plan to tow a larger pop-up trailer and other toys in a utility trailer so 20 extra HP and 20 extra foot-pounds of torque are certainly welcome even if it's higher in the power band. But I'm also planning to run an under drive pulley and RV6 J-Pipe with high flow pre-CATs to complement the rest of my higher flow exhaust. Once it's on, if I have the opportunity to put it on an AWD dyno, I'll do so just to see how many wheel HP I gained with the mods.

[N_Jay]

Well, I tow a trailer that weighs in at 2800 LB dry and a wife that packs 1/2 the house, so with something close to 3500 LB and a stock '03 I find it does fine.

What EVERYONE seems to miss is any EXTRA HP and torque ONLY show up UNDER FULL THROTTLE.

Now if you actually get the throttle down to the floor for very long, you are doing something wrong in terms of towing.

As for the under-drive pulleys, they are great for high RPM, but under power accessories at normal RPMs.

Sorry your opinion disagrees with the facts, but we are all about sharing information.

Sorry if you consider facts "pissing on the thread" but considers a 7% increase only at full throttle and high RPM "meaningful"

[macphanatic]

I put a K&N CAI on my F-250 Super Duty. It did nothing except for making the truck louder. No additional power and fuel economy did not improve. Just because K&N has graphs on their website doesn't make the "improvements" true.

[BoilermakerFan]

If the extra power only showed up at full throttle then the curves would be identical up to the full throttle peak, but the curve is stepped up over the entire power band. It's not the full 10HP gain, but it's a gain at the wheels from 2500rpm on with the stock exhaust.

We have very different philosophies. I'm fine with the 20 extra HP at the wheels in the last 1,000rpm. Do I drive to redline every time? Nope. Do I take up the revs to hear V-TEC kick in when I'm running unloaded by myself so I can hear that sweet music out of my MagnaFlow exhaust? Yeah, occasionally though the gas mileage hit brings me back to reality quickly. However, I sure as hell want that extra power there when I really need it to quickly squeeze into a hole and get the hell out of the way of a hopped-up truck driver who is trying to mow down 4-wheelers... or when merging into heavy traffic where aggressive drivers simply won't cut you a break and let you in. The ol', "earn your merge" attitude that is unfortunately becoming more common even in smaller cities where traffic is becoming a problem.

I'm well aware that the under drive pulley under powers the accessories. I'm going with a corrected aftermarket higher output DC Power alternator to accommodate the under driven alt, but I've run lightened under drive pulleys on my two other vehicles with no detrimental side effects for over 110K on one and 90K on the other before trading them both in on the Pilot.

I guess I'm a little confused by your statement that under drive pulleys are high rpm gains too. Look at the dyno charts from Unorthodoax Racing or others. The torque curves jump right off idle and stay above for most of the posted charts. There are only a couple where torque curve shifted to trail the OE curve, but the Honda curves all have much higher initial torque gains and stay relatively flat in the gains or follow the stock curves with only slightly higher incremental gains in the higher revs.

I am upgrading the flip side of the extra power too. I'll be putting on much better aftermarket rotors and more aggressive, lower dust pads as well as better tires to improve stopping when the drag race from the stop light to the camp site is over.

[BoilermakerFan]

Originally Posted by macphanatic

I put a K&N CAI on my F-250 Super Duty. It did nothing except for making the truck louder. No additional power and fuel economy did not improve. Just because K&N has graphs on their website doesn't make the "improvements" true.

Fair enough. But my main reason for buying the K&N kit was to see if it fits and if it does, allow me to run a much better Volant PowerCore filter so I'll have the ability to pull more air in later when I need it.

I'll have an aftermarket exhaust complete this week with the addition of the MagnaFlow resonator and I plan to replace the pre-CATs and J-Pipes when RV6 has them ready for the Pilot.

Talking to Vortech and Hondata about a little forced induction down the road too, but for now, I'll leave it at the intake air filter, lightened under drive pulley, and exhaust.

[N_Jay]

LOL, You get the curve by running the engine at FULL THROTTLE into the Dyno load.

It is simply a chart of "PEAK" power at each RPM.

OK, so what is a "meaningful" increase in HP? 2%? 5%?

At what RPM do you see that increase?

[Boardorgohome]

They do make alternatives to underdrive pulleys, as in a lightened pulley. I believe unorthodox racing has underdrive and standard drive lightened pulleys...

[BoilermakerFan]

Originally Posted by Boardorgohome

They do make alternatives to underdrive pulleys, as in a lightened pulley. I believe unorthodox racing has underdrive and standard drive lightened pulleys...

Yes, Unorthodox offers both and they even state that most of the HP gains are from the lightened pulley. They under drive by less than 20% so that the accessories stay within spec and even the alternator is fine for up to a 600W stereo. But, I'll be adding the DC Power alternator to gain some output and his alternators are more efficient and have better bearings so they have less drag too.