Intakes and Exhaust and MPG?
#21
03-11-2015, 01:47 PM
2015 LX CVT.....
Stock intake and exhaust - mpg on highway was between 44-47mpg
44mpg on stock wheels
47mpg on lighter wheels
After installing a custom cold air PRM intake and 2.25" TO 2.5" exhaust (Cats eliminated) mpg went down to 33mpg on average.
This is from driving the same way, on the same highway, the same directions, with similar temps.
Stock intake and exhaust - mpg on highway was between 44-47mpg
44mpg on stock wheels
47mpg on lighter wheels
After installing a custom cold air PRM intake and 2.25" TO 2.5" exhaust (Cats eliminated) mpg went down to 33mpg on average.
This is from driving the same way, on the same highway, the same directions, with similar temps.
Im considering putting the stock intake back in but leaving the muffler on. It didnt hurt the mileage and the sound of it sounds great for that little car
#23
03-11-2015, 03:25 PM
The new ones are probably more accurate than the older models (mines an 09 and is typically positive by 4-5 mpg). If its that big of a drop, than Id be afraid to mess woth a GK if I ever bought one. I have to wonder though if the cvt has anything to do with it for some reason...
#24
03-11-2015, 03:33 PM
When night hit, it was nice and cool again. Same thing on the hwy, and the mileage started to increase. Its made me come to the conclusion that either:
A) Warmer air is getting me worse mileage
B) The ECU still hasnt adjusted properly (and i started running 93 at the same time from 87 so im not sure if that has anything to do with it.
C) I haven't done enough to the exhaust?
So at this juncture, I'm inclined to believe the stock airbox is the most effecient. But I guess Ill find out once I do a Fill up test lol
A) Warmer air is getting me worse mileage
B) The ECU still hasnt adjusted properly (and i started running 93 at the same time from 87 so im not sure if that has anything to do with it.
C) I haven't done enough to the exhaust?
So at this juncture, I'm inclined to believe the stock airbox is the most effecient. But I guess Ill find out once I do a Fill up test lol
#25
03-11-2015, 03:37 PM
So the intake changed your shift point? Sounds more like the butt dyno talking.
Warm air is better for mileage. Cold air's higher density lets you burn more gas for power- and adds to the aero load, a big penalty on something as unaerodynamic and underpowered as a Fit. Lots of things could have changed for the nighttime run to get better mileage, but I don't think it was the cooler temps. Give things time to settle out, you'll figure out what's changed.
Warm air is better for mileage. Cold air's higher density lets you burn more gas for power- and adds to the aero load, a big penalty on something as unaerodynamic and underpowered as a Fit. Lots of things could have changed for the nighttime run to get better mileage, but I don't think it was the cooler temps. Give things time to settle out, you'll figure out what's changed.
#26
03-11-2015, 04:24 PM
That's the plan. Though eventually im also going to upgrade the midpipe and catalytic converter and headers. Does anyone know if the performance headers for the GD Fit would work for the GE? Ive looked on andysautosport.com and found 2 that say 07+ but wasn't sure if theyd work for my 09. Im also looking to do the MAF sensor if possible.
T1R:
http://www.aj-racing.com/shop/produc...6&cat=0&page=1
http://www.aj-racing.com/shop/produc...0&cat=0&page=1
Weapon R:
http://www.carid.com/weapon-r/stainl...FbBj7AodzyQA_A
Last edited by FittinglyFittedFit; 03-11-2015 at 04:29 PM.
#27
03-11-2015, 10:57 PM
I guess im reviving a dead thread here lol
I just put an hps short ram intake on, got rid of that extra tube and installed two breathers instead. Also, a week before that I put the Tanabe catback exhaust on. The mileage with the exhaust stayed the same but its possible i didnt give it enough time for the ecu to adjust.
The intake...is a different story. When it was installed, it was nice and cool outside. I immediately noticed a change in acceleration. In first gear, WITHOUT S mode being on, the car revved all the way to the redline before shifting, so I was satisfied. However, I generally drive 52 miles to work and 52 miles back on the hwy 5 days a week. I live in Florida, on the east coast, and while driving on the hwy at 65, my "avg mpg" display started to decrease.
However, it was hot outside. When night hit, it was nice and cool again. Same thing on the hwy, and the mileage started to increase. Its made me come to the conclusion that either:
A) Warmer air is getting me worse mileage
B) The ECU still hasnt adjusted properly (and i started running 93 at the same time from 87 so im not sure if that has anything to do with it.
C) I haven't done enough to the exhaust?
So at this juncture, I'm inclined to believe the stock airbox is the most effecient. But I guess Ill find out once I do a Fill up test lol
I just put an hps short ram intake on, got rid of that extra tube and installed two breathers instead. Also, a week before that I put the Tanabe catback exhaust on. The mileage with the exhaust stayed the same but its possible i didnt give it enough time for the ecu to adjust.
The intake...is a different story. When it was installed, it was nice and cool outside. I immediately noticed a change in acceleration. In first gear, WITHOUT S mode being on, the car revved all the way to the redline before shifting, so I was satisfied. However, I generally drive 52 miles to work and 52 miles back on the hwy 5 days a week. I live in Florida, on the east coast, and while driving on the hwy at 65, my "avg mpg" display started to decrease.
However, it was hot outside. When night hit, it was nice and cool again. Same thing on the hwy, and the mileage started to increase. Its made me come to the conclusion that either:
A) Warmer air is getting me worse mileage
B) The ECU still hasnt adjusted properly (and i started running 93 at the same time from 87 so im not sure if that has anything to do with it.
C) I haven't done enough to the exhaust?
So at this juncture, I'm inclined to believe the stock airbox is the most effecient. But I guess Ill find out once I do a Fill up test lol
you make a common misunderstanding. either increasing combustion efficiency
via better spark or by decreasing the work required by the engine from less restriction in intake or exhaust that results in the engine working less hard is not a measure of the power increase. the injectors issue just as much fuel but burns less, or more, or making the engine work less or more hard is not a power increase. It is merely increased operating efficiency, why one engine will develop more power than another of the same displacement. to determine if more power is generated you must not change the engine to compare power. Racers change the fuel input all the time by merely changing injection rates from bigger jets or more injection time without changing engine parts. for a given rpm they will indeed produce more power simply by burning more fuel. and when changing parts generally the first dyno runs use the same fuel feed rates to see if it made more power. after that we change the fuel ingestion rate and time. its not a good idea to do both at the same time..
Look at it this way: the only way power is generated is by burning fuel; more power requires more fuel. changing the engine isn't a comparison of power but of changing efficiency of the design. changing the design prevents a comparison of power..
#28
05-12-2015, 05:06 PM
Thanks again everyone for the replies. In the time ive had the setup on, i haven't really noticed any mpg increase and dont expect too. It does seem to respond better than before though, but i just had a bit of a question.
I noticed that some people who have done dyno tests have stated that, stock, their hp is in the 90s to low 100's. The car is supposed to be rated at 117 hp so heres the question: are the stock intake and exhausts making our cars lose its peak power? Or was honda lying to us? Does it depend on the dyno or the ammount the cars been driven?
I noticed that some people who have done dyno tests have stated that, stock, their hp is in the 90s to low 100's. The car is supposed to be rated at 117 hp so heres the question: are the stock intake and exhausts making our cars lose its peak power? Or was honda lying to us? Does it depend on the dyno or the ammount the cars been driven?
#29
05-12-2015, 05:57 PM
Thanks again everyone for the replies. In the time ive had the setup on, i haven't really noticed any mpg increase and dont expect too. It does seem to respond better than before though, but i just had a bit of a question.
I noticed that some people who have done dyno tests have stated that, stock, their hp is in the 90s to low 100's. The car is supposed to be rated at 117 hp so heres the question: are the stock intake and exhausts making our cars lose its peak power? Or was honda lying to us? Does it depend on the dyno or the ammount the cars been driven?
I noticed that some people who have done dyno tests have stated that, stock, their hp is in the 90s to low 100's. The car is supposed to be rated at 117 hp so heres the question: are the stock intake and exhausts making our cars lose its peak power? Or was honda lying to us? Does it depend on the dyno or the ammount the cars been driven?
#30
05-12-2015, 09:39 PM
Thanks again everyone for the replies. In the time ive had the setup on, i haven't really noticed any mpg increase and dont expect too. It does seem to respond better than before though, but i just had a bit of a question.
I noticed that some people who have done dyno tests have stated that, stock, their hp is in the 90s to low 100's. The car is supposed to be rated at 117 hp so heres the question: are the stock intake and exhausts making our cars lose its peak power? Or was honda lying to us? Does it depend on the dyno or the ammount the cars been driven?
I noticed that some people who have done dyno tests have stated that, stock, their hp is in the 90s to low 100's. The car is supposed to be rated at 117 hp so heres the question: are the stock intake and exhausts making our cars lose its peak power? Or was honda lying to us? Does it depend on the dyno or the ammount the cars been driven?
Second, there are significant differences between individual dynos as their measurements vary , usually not over 5 % but the thats 5 hp at 100hp.
Third, every engine is different in its horsepower curve. Some are above average, some below and a spread of 10% is not unusual.So we can expect hp to vary by as much as 10 hp in a hundred and then there is the hp lost pasing thru the transmission. Typically the horsepower generated on a car dyno, meaning at the wheels, generally runs about 80 to 85% of the advertised engine horsepower. that was a key reason why competitors employed by manufacturers who competed in showroom stock racing were generally winners. Once C&D ran a comparison between doge racers and off the showroom same models were 50% slower in acceleration yet met the rules.
If you want maximum hp curves you must hand build your engine; its not unusual for hand built off the showroom floor gaining 25%
what you get in your off the shoroom car is a gamble as to its performance.
#31
05-24-2015, 12:56 PM
New highway test on GK.
Intake - Custom SRI-CAI (Ram-Air)
Exhaust - J's Circuit Converter, J's B-pipe and J's 50R Muffler
Run 92 Octane (Always)
Was hitting 45-46mpg on the way back from track.
Silencer has been installed now which significantly reduces exhaust diameter. Will update after testing!
Intake - Custom SRI-CAI (Ram-Air)
Exhaust - J's Circuit Converter, J's B-pipe and J's 50R Muffler
Run 92 Octane (Always)
Was hitting 45-46mpg on the way back from track.
Silencer has been installed now which significantly reduces exhaust diameter. Will update after testing!
#32
05-24-2015, 05:05 PM
No one is reading into one other thing causing a drop in mpg potentially. Its the piping size of his exhaust. 2.25 is the size of most after market exhausts for 4cyl. Stock size piping is 2in or less in the fit. 2.25 is aftermarket. Here's a question for you guys to ink through. How much air do u really thing a 1.5l is ingesting that it warrants the size of stock turbo piping? 2.5in reduces the low end by a lot so you floor it longer burning more fuel.
#33
07-06-2019, 06:06 PM
i have the AEM intake with the medallian axel back . probably the biggest bump in power comes from the intake , the addition of the
axel back was stil a nice little step up . last fall i added an HKS B pipe . i'd say the benifits were questionable .at low rpms it seemed stronger ,
up past 60 the car was just as fast but with a bit of a flat spot getting there . the mileage went down a bit .i ended up putting the stock B pipe
back on .been averaging 35 - 36 MPG , highway is in the high 40's . the big B pipe was loud , droned alot
axel back was stil a nice little step up . last fall i added an HKS B pipe . i'd say the benifits were questionable .at low rpms it seemed stronger ,
up past 60 the car was just as fast but with a bit of a flat spot getting there . the mileage went down a bit .i ended up putting the stock B pipe
back on .been averaging 35 - 36 MPG , highway is in the high 40's . the big B pipe was loud , droned alot
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