90Rexx

Ok so everyone has heard every myth and rumor about what improves and decreases gas mileage. So i have decided to compile a complete study on what improves fuel mileage and by how much. My guinie pig for this study will be a 1997 civic cx hatchback with an origional D16y7 no mods.
the details of the guinie pig are:
211,xxx miles
no a/c
no p/s
conventional oil
conventional gear oil
E3 spark plugs brand new
dirty air filter
original fuel filter
32 psi tires

how the experiment will work:
My daily commute is about 95 miles back and forth. It is 98% highway. This will give a very consistent test. I will start with a full gas tank and go to work and back. i will return to the same gas station and refuel to the top again. this will give me my total fuel consumption in gallons and my trip will give me mileage.

each experiment will have two runs for consistency.
different experiments will include:
-what is the ideal cruising speed. 65-80 mph
-what is the ideal tire pressure? 28-40 psi
-dirty vs clean air filter
-dirty vs clean fuel filter
-copper vs platinum vs iridium vs E3 spark plugs
-synthetic vs conventional gear lube
- fuel injector products
-new 02 sensors vs old ones
** if anyone has any ideas or would like to see a product tested please let me know.

I would also like to get into testing some performance products for fuel mileage increases such as intake systems and those tornado supercharger things. some argue these increase fuel mileage as well.

The control test will be performed on 8/20 and 8/21 and the average of the 2 trips will give me my civics mpg as it stands. from there i will move on.

* note: doing some preliminary testing, i found that 86 miles of about 1/2 highway and half main roads with an average amoung of stops netted me a 47.7 mpg rating. ( consumed 1.8 gallons.) i find this to be abnormally high, which is what sparks my interest in this testing.

*EDIT*

I am also in the process of designing a complete 2 cylinder conversion for d series engines. I expect this conversion to net about 70 mpg total fuel economy if all goes well. I have done very extensive reseach on this so far and there are still many hurdles to overcome. The details of the project will be kept a secret but the conversion will adress engine vibration, engine power, and is not just a simple unplug 2 injectors and call it a 2 cylinder. more details on this project will be released later. Currently im looking for a doner D16Y7 cylinder head to start work on. if anyone has one lying around it would be very much so appreciated. your donation will let you in on the project and all its details.


Modified by 90Rexx at 5:53 AM 8/19/2008

Perfectionist

FWIW, in my experience, your trip distance between refills is too short. I refill (about 3/4 tank low) at the same station in the same manner and drive the same route the same way every time. The result almost always has a pattern of every other refill indicating higher fuel mileage. (example: 32mpg, 34mpg, 31mpg, 35mpg, etc.) In my case I have to average out the mpg over several fills to get a true measure.

Some of your other tests can be eliminated by common sense. Higher tire pressure will result in less rolling resistance and result in higher fuel economy. But, ride and handling, not to mention safety, can suffer. Lower cruising speed will have less air resistance and require less energy to overcome. If the old O2 sensor is over 80k miles, a new one will most likely result in some improved mileage figures, but you have to weigh cost vs. benefit here. Clean air filter, if for no other reason, will protect the engine. Stock type OEM NGK or Denso plugs spec'd for your application are just fine. Forget about the "Tornado". Too many tests and common sense can rule that one out.

Good luck on your experiment and keep us updated on your results.

90Rexx

i understand completely what your saying, but im more leaning towards cost vs. improvement here. an oxygen sensor runs about 80 bucks cheapest i could find....will you ever get that 80 dollars back in fuel costs and how long will it take? thats more so the questions im trying to answer. obviously most of these things will improve mileage, but by how much, and how worth it is it to invest in? i think the oxygen sensor is gonna be a bust. too expensive for what i think it will return you in savings. also fuel filter i think will be a bust, but we shall see!

ohsnapzafingcu

iTrader: (2)

i put a velocity stack and a "cleaned" k&n filter and i got about an extra 20-30 mpg on my 99 civic ex.. i was smashing and racing myself everywhere and still got that improvement..

eg6sirll

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ohsnapzafingcu &raquo;</TD></TR><TR><TD CLASS="quote">i put a velocity stack and a "cleaned" k&n filter and i got about an extra 20-30 mpg on my 99 civic ex.. i was smashing and racing myself everywhere and still got that improvement..</TD></TR></TABLE>

extra 20-30?? probly just like you gained an extra 20-30 whp by installing that k&n. who won when you raced yourself??

90Rexx

ok so this experiment is a no go....timing belt snapped....oh well.....

ElCoronaCartel

http://www.fuelly.com/

thought that might be of some relevance, its a cool site i was referred to on the 300zx forums.