Possible 6% mpg gain from adding a cone filter...Ford Focus...

[suspectnumber961]

Looks like maybe a 2 mpg (6%) gain from just adding a cone filter. I've had this filter laying around for a few years from another car....didn't think it would help since I already had the restrictive cold air intake nozzle removed from the pipe going to the front...and also the resonator box was removed allowing air from under the hood into the filter box.

IAT is probably close to the same as before...around 10F higher at 70F...3-4F higher at 90F vs ambient....so it's not likely a warm air issue.

Took 1/2 tank or so for the ECU to adjust.

Filter is laying on a piece of foam....OD of intake pipe and the filter pipe are the same...thus the tape and clamp. Just clears the hood.

[Frank Lee]

I am glad you put "possible" in the title.

[suspectnumber961]

My mistake. I meant GUARANTEED.

[MPGranger]

I once owned a Pontiac Vibe GT, aka Toyota Matrix (rebadged!). When I was younger I installed a K&N cold air intake full air system. I did see a noticeable jump in FE along with POWER, which younger me was all about. A few months later at an autozone I was bored and looked in the K&N book hanging off a chain and they were claiming a 15hp boost. I never tested the claim with anything more sophisticated than the seam of my pants. I do know smaller cars are choked by the EPA, my buddy got a intake system for his Ranger's 3L V6 and didn't see much difference.

[HydroJim]

Please do more testing because if this is true, I'll have to install one of these on my focus.

[ksa8907]

Noticed a similar increase on my intrepid when made they switch 6 years ago. I assumed the engine had slightly less vaccum under acceleration, maybe adding a little torque.

[t vago]

Originally Posted by suspectnumber961

Looks like maybe a 2 mpg (6%) gain from just adding a cone filter. I've had this filter laying around for a few years from another car....didn't think it would help since I already had the restrictive cold air intake nozzle removed from the pipe going to the front...and also the resonator box was removed allowing air from under the hood into the filter box.

What caused the improvement? Removing the cold air inlet? Removing the resonator? Changing from a probably dirty filter to a likely clean filter? A combination of all 3 actions? What?

Originally Posted by suspectnumber961

IAT is probably close to the same as before...around 10F higher at 70F...3-4F higher at 90F vs ambient....so it's not likely a warm air issue.

So.... in other words, you don't know whether IAT has changed.

[mwebb]

Originally Posted by suspectnumber961

My mistake. I meant GUARANTEED.

this is a CROCK O POOH
the EPA IATn BITOG AutoSpeed have all performed A B testing with various
"alleged performance" air filters including K & N
none of them (the tested filters) increase flow or fuel economy in any way at all at cruise
above a stock air filter

and the testing also shows that the K & N air filters do not actually "filter" the incoming air as well as stock OEM air filters

as you know the MAF sensor only samples a small percentage of the entire air flow and if the flow at the sample area is disturbed or re routed by tampering with the air box assembly then ....

your POS cone air filter very likely is not directing air flow to the MAF sensor correctly (as designed) and because of that the MAF is under reporting
this results in changes in the way the ECM assigns values to many thing
including spark timing and injector pulse width

you can test my theory by providing long term fuel trim with calculated load and MAF flow values and ign timing values at 55 mph on the same stretch of highway with your new POS filter and the original OEM filter

any generic OBD2 scan tool that can show real time live data can perform this task.

until then
this should be relegated to the UNICORN thread as it is bogus .
imho

[pete c]

The K&N filter may do one thing. It may increase max hp. It will do nothing mileage wise for any vehicle with a throttle, since any increase in flow will simply mean that you will close the throttle a little to compensate.

This really ain't rocket surgery.

I think that a low restriction air filter might make a bit of a difference on a diesel as it will lower pumping losses.

[Frank Lee]

We have been down this road 1000 times already. Unicorn.