the best MPG i ever got in my 00 Si was the first 2 tanks after purchasing it new, while breaking it in...maybe 31 mpg. after that, well let's just say wide open throttle and vtec was very common, so gas mileage was thereafter a solid 25 mpgs.

now that the motor is built I have been driving the car again...last week on the way up to Reno, i got 28.5 mpg...not bad considering its uphill. on the way down, i got 31 mpg, which makes sense, because its downhill and i was coasting most of the time.

today my wife went shopping all day and got 34 mpgs!!! wtf i have never seen my car get this mileage, and now its like totally modified....is this normal?

my air fuel ratio is in the 14's cruising and in the 13's when the throttle is wide open, based on trial and error with RC 310s on CROME set at 325 injectors and i believe 47 psi on the fuel pressure...

 

I would believe the better mpg but 34mpg is outstanding! In one of Endyne's project cars, they were able to get better mpg with better compression. My car drives and consumes fuel better. Not too bad for CTR pistons.

 

My LSVTEC with P30's and Skunk2 Pro2+'s gets a consistent 30mpg.

...Compared to my B16 with Skunk2 Stage 1's and bolt-on's that got 23mpg...

 

it has to be the nice tuning

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by allaboutdaz &raquo;</TD></TR><TR><TD CLASS="quote">it has to be the nice tuning</TD></TR></TABLE> that's whats buggin me - it's all self/street tuned, with no datalogging or anything....i'm wondering if i set it too lean lol although the a\f ratio seems stable....

 

That is about right. Several simular n/a setups I have tuned get 30-33 mpg

 

update:

30k on the build and I just got <U>36mpg</U> on the way to LA last Friday.

I'm currently running stock fuel injectors, manifold, and fuel pressure regulator. I also cut the AEM CAI into a shorty for the wet winter weather.

 

how big are your wheels?

 

damn, thats good gas mileage. i do a lot of street driving to work and such and get around 28mpg. if i drive long distances, i get around 32-33 mpg.

its all about the tuning and making sure that your ignition and fuel components are healthy and working properly. it doesnt take much gas to get these motors running correctly. it sure beats any v6 or v8

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ( o )( o ) &raquo;</TD></TR><TR><TD CLASS="quote">update:

30k on the build and I just got <U>36mpg</U> on the way to LA last Friday.

I'm currently running stock fuel injectors, manifold, and fuel pressure regulator. I also cut the AEM CAI into a shorty for the wet winter weather.


</TD></TR></TABLE>

CAI reduces MPG.
i initially thought CAI just made the vehicle more efficient, but i read somewhere that cold air induction actually causes the car to "eat" more gas.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ipodhustle &raquo;</TD></TR><TR><TD CLASS="quote">CAI reduces MPG.</TD></TR></TABLE>
Huh?
Made a 400 mile trip with an ITR CAI averaging 90+mph, with a couple of full throttle bursts and the car got 25 MPG+. Driven conservatively (around 75 MPH) the car gets ~33-35 MPG.
Maybe if I tried a short ram I could get 40 MPG?

 

supernatural: my 2000 Si has stock wheels with 205/50's. I like the stock look.

ipodhustle: interesting note on the CAI. i kinda thought the stock injectors might have more to do with the mileage, but either way, my MPGs have increased for long trips.

btw this car has over 203,000 miles now.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b19coupe &raquo;</TD></TR><TR><TD CLASS="quote">
Huh?
Made a 400 mile trip with an ITR CAI averaging 90+mph, with a couple of full throttle bursts and the car got 25 MPG+. Driven conservatively (around 75 MPH) the car gets ~33-35 MPG.
Maybe if I tried a short ram I could get 40 MPG?</TD></TR></TABLE>

btw my average that day was easily 85-90mph with full throttle bursts throughout the day as well.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b19coupe &raquo;</TD></TR><TR><TD CLASS="quote">
Huh?
Made a 400 mile trip with an ITR CAI averaging 90+mph, with a couple of full throttle bursts and the car got 25 MPG+. Driven conservatively (around 75 MPH) the car gets ~33-35 MPG.
Maybe if I tried a short ram I could get 40 MPG?</TD></TR></TABLE>

you know..there's been arguments on both sides.
if your car is able to breathe better, than it should program that much more fuel in the mix without running too lean, right?

then again if it makes power with less effort, a disciplined driver can attain more mpg with a CAI?

*shrugs*

i never said it was a dramatic difference, though.