I just finished a full tank of gas with the K&N FIPK. The average MPG has gone down to 16.7 MPG, compared to 17.9 from the last fill-up (with Borla drop-in). Which is appx 1.2 MPG decreasement. Above numbers are base on trip computer. The K&N sounds nice when paired together with Borla, but it's very load under heavy acceleration. Lets try couple more tanks to see if MPG is consistant.
MPG Before vs. After K&N FIPK installed
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CuzzinOlaf
New member
Koz said:
Exactly. An air intake system should increase your gas mileage but not until the ECU adjusts itself.
CuzzinOlaf
New member
MDT4RNR said:
I never said unplug the battery.
It's easy to understand why improvements to the intake system help: If you've ever tried drinking a really thick milkshake through a straw, you know how hard it can be to pull that fluid through an opening that's too restrictive. Your engine may be feeling the same way about incoming air.
Exhaust system changes work pretty much the same way: If your engine is trying to force its spent gases out through an opening that's too small, it's wasting energy. Plus, if there's too much backpressure, some exhaust may remain inside your engine, which means there isn't as much room for fresh air and fuel to be burned, so you're making less power.
Re: Re: MPG Before vs. After K&N FIPK installed
It doesn't matter which calculation methods being used since the comparison before and after used the same recorder (trip computer). We've already know that trip computer is slightly higher than actual MPG, lets say hand calculated. Here's the hand calculation result base on number of miles divided to the number of gallons of gas on the last two's receipts.
311miles : 18.72 gallons = 16.61 MPG (Pre K&N)
307miles : 19.89 gallons = 15.43 MPG (Post K&N)
Differential : 16.61- 15.43 = 1.18 MPG
JB. said:
It doesn't matter which calculation methods being used since the comparison before and after used the same recorder (trip computer). We've already know that trip computer is slightly higher than actual MPG, lets say hand calculated. Here's the hand calculation result base on number of miles divided to the number of gallons of gas on the last two's receipts.
311miles : 18.72 gallons = 16.61 MPG (Pre K&N)
307miles : 19.89 gallons = 15.43 MPG (Post K&N)
Differential : 16.61- 15.43 = 1.18 MPG
jeober
New member
Restriction (pressure drop) across the air filter will not impact mpg. At part throttle there is huge pressure drop across the butterfly plate -- this is what causes engine vacuum in the intake manifold. A drop across the filter is miniscule in comparison, and even if high the butterfly would open up slightly to compensate for the same engine load. The engine computer always meters the fuel in proportion to the mass air flow.
Now, at WOT a pressure drop could cause a power loss since less air mass is filling the cylinder. But again, the power loss is not a loss of mpg.
Now, at WOT a pressure drop could cause a power loss since less air mass is filling the cylinder. But again, the power loss is not a loss of mpg.
Northof49 said:
Uhhh! I only heavily footed 3 or 4 times to test the throttle response. It's not going to need that much gas, is it?.
"Northof49"
Does it make any more noticeable power?
Nah! Nothing noticable at all. Power gain will be minimal, if any. However, throttle responds much quicker and sounds throatier, but damn loud at WOT.
greasefingers
New member
Flow Rate with the paper OEM air filter
Flow rate with filter removed
There is no difference, therefore there is no restriction.
1000 data points were collected for both tests
The scatter around 1500, 2000, 2500, & 3000 rpms is because it is difficult to hold your foot steady at specified rpms for long periods of time.
Flow rate with filter removed
There is no difference, therefore there is no restriction.
1000 data points were collected for both tests
The scatter around 1500, 2000, 2500, & 3000 rpms is because it is difficult to hold your foot steady at specified rpms for long periods of time.
Koz
New member
greasefingers said:Flow Rate with the paper OEM air filter
Flow rate with filter removed
There is no difference, therefore there is no restriction.
1000 data points were collected for both tests
The scatter around 1500, 2000, 2500, & 3000 rpms is because it is difficult to hold your foot steady at specified rpms for long periods of time.
Put the beer down and step away from the computer!:beer:
Koz
greasefingers
New member
When I co-plot the two graphs, the lines lay on top of one another. It is pointless to think that one can get more air into a system that only draws a specific amount. Unless there were a restriction.
Koz
New member
greasefingers said:
There has to be some restriction. It may be too small an amount for your scanner to record. I can see a difference between the two graphs. Is there a setting to reduce the scale to show finer detail? Also a less restrictive exhaust will make more of a difference.
Koz
