yet another WAI experiment

[GasSavers_BEEF]

my results:

+2.7475%

the experiment: 6 tanks of no less than 400 miles each alternating from stock to WAI. I couldn't go completely back to stock. I have two opening in my airbox that I can chose from. close off one and it is WAI, close off the other and it is close to stock. my stock IAT readings were about 5 degrees above ambient. my "simulated stock" readings were 17ish degrees above ambient. keep that in mind.

I do not have a data logger so all of this had to be taken by hand. the weather data came from www.wunderground.com (thanks to theholycow for the web site).

this big blue number means nothing without backup so here that is as well:



and pretty graph



all of this data can be seen in my gas log.

explinations and theories:

the first two tanks (I think) were during winter gas and thus the lower numbers. the entire run was over 2500 miles using over 70 gallons of fuel and took approximately 2 mos and 10 days. the IAT numbers were recorded at the end of each run (runs were between 20 and 30 miles on average).

so why was the net gain not better? part of it has to do with the temperature delta. at only 50 degrees (maybe 55) it isn't as large as most and the fact that my IAT only saw an average high in the mid 140s vs others that constantly run 180s.

is it worth doing? my driving was not different for this experiment and the power difference was only really noticeable on hard takeoffs from stoplights (if you question this, search GUNNING IT FOR FE). the actual cost of the setup was around $10 so the expense was minimal.

am I happy with the results? no and yes at the same time. I wish the percentage was higher but at the same time, it is a consistant increase as evident by my numbers and cheesy graph.

hopefully this isn't too much information at one time. and I am in no way saying that the WAI is a success or a dud as it depends on the vehicle and the drivers application along with other factors. I think it has been a success for my application and hopefully this will encourage others to experiment.

if anyone wants more data, I have each run in a rather lengthy excel spread sheet.

thanks for reading

[GasSavers_maximilian]

The effect's too small to be definitive given the sample size, alas. That must've been a lot of work! How did you choose to report the IAT readings? Mine vary a bunch when I'm driving.

[GasSavers_BEEF]

I took the IAT reading after I parked at the end of each run. what you see in the post is the average for each run. I had about 19 data points for each tank. these data points included date, time, and IAT at the runs end. after a fill, I went back and added the weather data from the above mentioned site.

one thing that I forgot to add is that I got gas from the same station, same pump, and always on the slowest automatic setting. I let it stop automatically and that was it.

I don't always do that because I run between 2 or 3 different towns during the course of the week (and sometimes day). that may have been a factor in my favor. (now I really am making excuses)

[R.I.D.E.]

Beef, do you have data for winter time temperatures when the difference may be greater?

regards
Gary

[GasSavers_BEEF]

no, I don't

it was suggested to me but this experiment took ~2.5 months to take the data. these are just the averages of the data I took. I could fill this thread with the data I took but there would be little point in that.

I have thought about redoing it in the winter months. the problem becomes that I like to warm my car in the winter (old habbits die hard) and any bad weather like snow and sleet tend to skew results as well.

also, since my daughter came along, I rarely have time to even update my gaslog. (been keeping up so far)

your comments about it having more of an affect under 70 degrees F make me think that I could get better in the winter though. at least it is showing a positive affect regardless of how small.

[GasSavers_BEEF]

for anyone interested, here is the raw data that I have for the 6 tanks. red is obviously during the HAI and the blue is normal(ish).

apologies beforehand for the HUGE amount of data below

[i-DSi]

Originally Posted by maximilian

The effect's too small to be definitive given the sample size, alas. .

I think the effect is obvious. Almost 3% better is a lot.

[GasSavers_BEEF]

his point was that my tank to tank deviation was around 1.5-2% before that so it is hard to say how much of that isn't just standard deviation.

one thing I did for this experiment (which I normally don't do) is fill up at the same station, same pump, on the lowest setting on the tank. I usually just fill up wherever and whenever I need gas. I feel like this step actually increases my accuracy that much more to further validate these numbers.

[FrugalFloyd]

Unfortunately, this was not ABA testing. Testing full tanks just opens too much variability in road and traffic, temperature, and other conditions. And since the benefits are so small, and within standard deviation, I don't think the WAI proponents can score this in their win column.

[GasSavers_BEEF]

so what you're telling me is that my test isn't good enough for you.

I'm not sure what more someone would want. this is the most accurate A-B-A test that you could do. I actually talked with several people about this test before starting it.

you could argue that several small runs would be better to take out variables but then you have such a small sample that you really can't say how much gas was used (at least down to the 0.000X of a gallon). your road conditions and other variables may be more controlled but at the above mentioned sacrifice.

you will never...NEVER get rid of all the variables. there will always be variables. also, I am not a big fan of burning gas just to be burning it (or to prove a point)

some have said that short runs aren't conclusive because of the short run, others say that doing it tank by tank isn't conclusive because of the variables.

here is the deal. people asked for test results...here they are. take it, leave it, at this point I don't care.

In the end, I actually got of my tail and did some testing (more than most can say)