HtxPrelude2K

There are a number of variables to consider here. First, like someone mentioned earlier, you can't solely base on your results based on the fuel guage. Typically the fuel pumper/sensor wears down, and doesn't calibrate the correct amount of gas in the tank exactly. In mine, I can drive about 70 before the needle barely trickle below "F". By like 135 miles, it's at 3/4. By half, generally it'll be at 200 to 240 miles. By 300, I'm down to 1/4 tank. The light shines bright and needle is on E, at about 390 miles. At fill up, it says about 14 gallons. Do the math here:

390 miles / 14 gallons = 27.85 miles per gallon (mostly highway)

The best things to do to maintain your vehicle:
1. Tune up (cap/rotor/plugs/timing/etc.)
2. Good tires (keep air at min 32psi; I add in an additional 2-3psi to compesate for cold weather -- cold air compresses in, so you lose air, the colder it gets) -- keep them balanced/rotated every 5000 miles.
3. 30K service at the dealership (transmission, brake, clutch, coolant, etc. flushed; fuel injection service, new fuel filter, ).
4. New/clean air filter and PCV valve
5. Steam clean your engine (less dirt to deal with, and retains conditioning on belts/hoses/etc.)
6. Use Mobil1 Synthetic oil 5W30 Extended Performance (change every 10k miles; synthetic flows better, and your initial starts up do not rev higher ).
7. Drive w/ windows closed
8. Throw out any extra weight (junk in the trunk, trash, etc.)

Good luck!

gogunkergorilla

If you do a lot of highway driving you can switch to an Accord transmission or just the 5th gear. You will get approximately the same highway miileage as an Accord which is ~30mpg, up from ~27.

Simple_Sauce

I just wanted to bump this thread cuz I'm getting 13mpg on my 98 auto with 170k miles. I think I'm about to try that seafoam stuff.

Giant_Bean

I just got 34 mpg on a road trip up to VT, with an H22a, and the F22 tranny, cruising at about 74 mph, great for mileage, not so great acceleration wise.

ShagPower

i bumped gas mileage on my civic with a b16 from 28-30mpg to constant 34mpg (city driving) by adding an password jdm intake, new spark plugs, wires, pcv valve...pretty basic stuff. The big jump came with the intake, i was really surprised.

dre2day

seafoam?

IrregularRice

Well you could get a 4th gen prelude S, With the F22A in it. I hit my trip meter when i filled my gas tank, i have 1/4 tank left and im sitting at 272 miles. lol and i'm heavy footed.

HondaFan0504

I have a 92 Si auto, and get around 380 mpg 75% highway 25% city on about 15.9 gallon tank, shifting every 2200 rpm using 92 octane Chevron "Supreme", I found using 89 octane "Plus" wastes more money and does not last as long.

waynecoSI

i just finished my first tank on my h23 vtec and i got around 350 to my tank in my 4th gen. Its much better than my stock h23 was but it had close to 200k miles

dre2day

Mobile 1 oil has this new oil out with a green cap. its 0-20w, says its great for better gas millage and is ok with most manufactures, I seen honda on there so if someone wants to try it let me know how it works out, before my oil change is due which is 400 miles away.

eric416

keep in mind the tank only fill to around 80% capacity to allow for pressure when its hot out. So your not really filling it up to 15 gallons

Simple_Sauce

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dre2day &raquo;</TD></TR><TR><TD CLASS="quote">Mobile 1 oil has this new oil out with a green cap. its 0-20w, says its great for better gas millage and is ok with most manufactures, I seen honda on there so if someone wants to try it let me know how it works out, before my oil change is due which is 400 miles away.</TD></TR></TABLE>
I wouldnt put it in my car, but thats what the oil that the hybrid civics use.

Lovemy99Lude

I get awesome mileage for my '99 Lude. I do road trips from Kansas City to Des Moines, Ia every other week. I can put 400 - 430 miles on my tank cruising at 70 mph. Thats about 32 mpg using only 13-14 gallons

4WSi_guy

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by dre2day &raquo;</TD></TR><TR><TD CLASS="quote">seafoam?</TD></TR></TABLE>

http://www.seafoamsales.com/motorTuneUp.htm

great stuff...I put it in about every 5 or 10 tanks. I also use it in the oil every oil change.

96-h22a1

seafoam works great 240mpt is atrocious i get 340 with my manual h22a1 4th gen, and that was with shitty 7-11 gas and shifting @ 3k rpm


4wsi guy you live very close to me, we should meet up sometime @_@

chitownrida

i never saw less than 20 mpg, as long as i wasnt in boost

was able to get 24-26mpg driving granny style around town

Windwalker

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by IrregularRice &raquo;</TD></TR><TR><TD CLASS="quote">Well you could get a 4th gen prelude S, With the F22A in it. I hit my trip meter when i filled my gas tank, i have 1/4 tank left and im sitting at 272 miles. lol and i'm heavy footed. </TD></TR></TABLE>

That would be me-Avg between 28-32 mpg on my 92S

Hawkze_2.3

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tenjintuned &raquo;</TD></TR><TR><TD CLASS="quote">neutral on downhill... hahah </TD></TR></TABLE>

Leaving it in gear and engine-braking actually uses less fuel

Inextricabledrvr

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Hawkze_2.3 &raquo;</TD></TR><TR><TD CLASS="quote">

Leaving it in gear and engine-braking actually uses less fuel </TD></TR></TABLE>

94vtecmn

X3

It says right in the Honda service manual, that the fuel injectors are turned off while the throttle position is at 0%, until 1100 rpms. Leave it in gear to improve mileage.

Kronn 98SH

So, it's official. After my header install & VAFC tune (to lean out the super-rich A/F), my mileage has increased from 20mpg to 24mpg. This is with 50/50 city/hwy super-aggressive driving.

coolharry

i really wish i would have kept up on this before i did the i/h/e with a test pipe to see the difference, but anyways -
93 si h23, about 75/25 highway/city just rolled over 165,000, shift anywhere from 3-4 grand and use cruise every chance i get.
got about 28.5 mpg.

i was pretty impressed actually

gonna do a tune up soon (wires,cap/rotor,fuel filter,pvc valve, and a valve lash) with the goal of breaking 30 mpg.

duDeSter4to0

Wow.. It's surprising how many preludes get so low mpgs'.. 200-250 on a full tank?!?! I got a 4th gen prelude, all stock except the rims, with a h23 5speed and i get about 320-330 on a full tank using 91 octane gas. and my front bumper is half hanging off! Usually going like 80 85 on the freeway! lol. That's Cali for ya'. And I always thought MY car got bad gas mileage.

Just thought I'd throw my 2 cents in there.. I'm pretty sure no one will probably read this because the last post was about 3 years ago!....... But i just popped my honda-tech cherry haha.

H_T_LUDE

I notice that i get engine ping running on 89unleaded heavy on the pedal after a stop or when in low rpm and give it full throttle. put in Midgrade, the pings not there and im getting 21-23mpgs, i know it should be better than that, but thats hitting vtec, keep my foot out of it and stays the same

TayLude

Damn that's terrible. I get 240 if I am flooring it at almost every intersection. Hmmm... Good spark plugs and wires, distributor cap and rotor, run some fuel injector cleaner, new air filter. Make sure your o2 sensors are good, catalytic converter can hurt fuel economy if it is old. Just keep it maintained.