After these previous threads:

https://www.fitfreak.net/forums/fit-...am-intake.html
https://www.fitfreak.net/forums/fit-...am-intake.html
https://www.fitfreak.net/forums/eco-...made-7mpg.html

I wanted to give an update on the in-city MPG. Well, after maybe 6 tanks over the last 2 1/2 months, I ran this last tank all the way through. It was topped off with 87 octane. Running 9.89 gallons through, I went 263 miles. That is an average of 26.59mpg for the entire tank. This was full-urban inner-city driving; no country, highway or interstate at all, with a range of normal-to-spirited style with no hypermiling at all.

Here is a list of any and all mods I can think of that might have a bearing:

8,000 miles on a 2007 Honda Fit Sport AT
Full Tank of 87 octane (topped off both times)
Royal Purple Synthetic Race Oil 5W30 running 3/4 quart Low (on purpose)
45psi of Nitrogen in tires
205/50/15 Hankook Ventus HRII H405 rubber
15"x7" Konig Next wheels
SSR Intake (Sid Short Ram)
No spare or jack (but I do have a 10" sub with amp and box)
250lbs Driver

Up until the intake and oil, I was averaging 20-23mpg at the most and that was, on occasion, really driving like Grandma Moses and trying to get the most out of it. I was disappointed when I first got the Fit. The city mileage was pitiful, and honestly it was no better than the 2005 Nissan Altima 3.5SE V6 I had just traded in. Highway mileage was below average as well, only getting 35-36 MPG at it's best. As reported before, I am now getting, on average, 42-44mpg even at 70-75mph.

I am quite pleased now with the Fit's mileage. With gas prices headed up with no end in sight, purchasing this car was a wise investment.

 

BTW, before anyone asks, yes, the IAT has been mounted properly in the intake elbow, the proper distance from the TB.

There was a big question as to if maybe my improved MPG on the highway was the result of the IAT not being subjected to the airstream inside the intake tube.

Well, the IAT has been mounted in the correct location for 6 weeks now. All the gloom and doom attributed to the IAT placement seemed to be unwarranted. I did not have unrestrained pre-detonation as shown by the clean and perfect spark plugs.

So it is my semi-educated opinion, that the previous placement of the IAT had little to no effect on air-to-fuel ratio.

 

so, AUTO OR MANUAL transmission?

 

8,000 miles on a 2007 Honda Fit Sport AT

 

I was in auto zone earlier and they had everything you list here... thanks for the write up... gonna have to spend some stimulus check money!

 

I have to agree with the OP that you are getting horrible mpg even for an AT.

I would suggest get rid of the extra weight like the audio stuff(~50lbs?)
I don't know if 250LBS is over weight for you or not but I would suggest loosing weight if s 250 is over weight(health and mpg reasons).

MOST importantly, I do not believe you were really driving like a grandma. I can squeeze 34mpg in the city out of my wifes AT 2008 CRV. However, I do recognize that I do not know your exact driving conditions so that MAY be the major problem for you.

For driving techniques I would suggest: Coast in neutral whenever possible up to lights, down hills, etc. Do NOT accelerate up hills. Accelerate slowly. Try not to use the brakes, which will teach you to let off the gas early and coast to a stop. Drive the speed limit or under it if possible. It takes lots of practice and thinking. Thinking ahead is key.

Also, Inflate your tires to 50 psi and Nitrogen gas does not make a significant difference.

Why are you running your car with less than required amount of oil and why use race oil?

 

Who are you talking about, OP? I am the original poster. And 26mpg in the city for spirited driving is horrible mileage?!? Really? wow, and here I was elated.

As far as the oil goes, running less and/or an oil with a higher lubricity helps more than you think.

Obviously you want to run enough oil so the engine has proper lubrication, but running a little shy of the factory recommended amount will cut down on windage and reduce parasitic loss.

Running an oil with a higher lubricity will also help reduce windage.

That is why I run Royal Purple Fully Synthetic Race Oil. Royal Purple's extreme lubricity and tendency to reduce foam, greatly reduce parasitic loss caused by crank windage.

I have dyno proof of the gains realized from my 2005 Nissan Altima 3.5 SE V6. I gained 11whp and 15wtrq when I moved from Mobil 1 fully synthetic to Royal Purple. This is tremendous! I swear by the stuff. It's an old drag racers trick.

 

Well, I was really addressing you driving like a grandma and you only achieved 20-23mpg.

 

And not that it's anybody's business, but I've lost 100lbs in the last 10 months.

 

Wow, good job on that. I have lost 50Lbs before and I am currently trying to loose about 12Lbs. Speaking of which it is time for me to run 3 miles. Good luck in reaching your weight goal. Food is evil, especially sweets!

 

Not so evil...just like everything...in moderation you should be ok.

Too bad my TV blew up or I'd head to the shop to buy stuff for my Fit on the list here. My check is going to the new TV I already bought. (credit card )

PS Woot for losing weight though...I to have lost 25lbs in 4 months...working on the other 25 or so...the fight for better mpg goes on.

 

My first thought on reading this is why are you running 20W50 when the car should have 5W20, or better yet, 0W20?

 

That was a typo. It's actually 5W30 Royal Purple. Sorry for the confusion.

 

I think what confuses people is that we tend to have different opinions on what we mean by city driving. I live in a city where I drive like 500 feet then have to come to a complete stop...then drive another 500 feet and it's a complete stop, really a bummer and makes mileage very bad. Now someone else may think a city is drive for a half mile slow down but not stop for maybe another half a mile. So I think the term city is what makes it hard to compare city mileage without an explanation of what you mean by city driving. Highway driving is easier to compare no stopping maintaining a certain speed maybe hills are a difference but city could mean a lot of things to lots of people.

 

That's what I was trying to say when I said:

 

that is a great point

I will have to keep track of how many miles I drive to work and how many stop lights on the way so that way i can give a more accurate claim of my city driving.

 

5w-30 is know to drop fuel efficiency. Most people have reported a 1-2 mpg loss. Maybe you should try 5w-20 next and see if you get 28 mpg instead of 26. And you're bound to lose about 1 mpg for each 100 lbs you put on your car because the weight adds to the coefficient drag on your tires. I've gone down to 20 mpg city driving transporting about 400-500 lbs of equipment, driving nonconservatively. Also, if you tend to run into every red light in the city, expect a mileage drop.

 

I think your car is just breaking in. And thats why the milage is going up.
There are to many variables here to attribute the gain in economy to a home-made intake tube.
My buddys Fit gets 34 or so in town, always, bone stock. I do not plan on changing a thing with mine.
After fooling around with my V10 Triton I have come to the conclusion the intakes do nothing for some engines, other than increase the noise.

 

this is to the OP,

If you want some oil that has very low resistance then try the 0w20(mobile 1 synthetic). I just put this in my car and this shit is like water!

It's suppose to give better mpg but it has got me worried how well it will protect.

 

Considering it's not an oil weight Honda recommends, it should be a source for worry.

what was the oil pressure before and after than change?