ABA testing power steering on/off

[aktacoma]

so on my tacoma it is very easy to run with no A/C or P/S because there are 3 seperate belts pone for A/C one for P/S and one for the alternator
so i did my ABA testing as follows:

tested at 53 mph with cruise control, truck warm, scan gauge reset for average mpg and measured once already up to speed

A:Belts off
33.4 mpg towards firehouse
39 mpg coming back
36.2 avg mpg

B:P/S belt on
34.5 mpg towards firehouse
39.5 mpg coming back
37 avg mpg

A:Belts off
34 mpg towards firehouse
41 mpg coming home
37.5 avg mpg
also there was a small wind causing the variation in to and from mpg but i thought I'd see what she did anyways..

definitely test could be improved on, faulty results because the avg kept going up as i tested however scan gauge read same temp the whole time so i know its warm enough.. anybody experience great results from this?

will leave both A/C and P/S belts off for a while and see how i like it and what mpg i can get i might have to increase my goal of 40 mpg to 50 mpg in my tacoma!!

I am in the middle of calibrating my scangauge II in between 1st and 2nd fill does this make any big difference on results?

[mcrews]

my infiniti Q45 experienced more vibration in the front end when I went about 500 miles with out the ps belt.
seems the rack and pinion need the preesure of the fluid to keep everything tight.
It steered ok, just a vibration that I knew would wear the tires unevenly

[kir_kenix]

My PS pump went kablooey on me the other day and I removed it. Still working on the first tank since I ripped it out, but it has definitely helped some. My going guess is somewhere between 1 and 2.5mpg based on trips I've frequented many times in the past. I can't see how it would damage a rack and pinion or gearbox set up, as long as there was still fluid in the system.
If I had to make my best educated guess, I'd say it's been worth 1.5mpg in my truck. Yours might be more or less depending on how much parasitic drag the unit had on your engine.

Regarding calibration, I've noticed a big difference on my second fill up. After that second fill up its been pretty good...with only a few percent deviation from there on out. My wife's car only required 1 fill up to get well calibrated, but both times I've had the SG out of my truck it took 2 fills to get her dialed in again.

[aktacoma]

ok but as far as % change it should be ok? i just went to town and on the way back got an average of 43 mpg but I was P&G some and then I just kept it at 53 hopefully that's what I'm actually getting in the truck!! before I pulled the A/C belt and the P/S belt drove that route earlier today P&Ging the whole way and got 36.4 mpg so i think it helped!

[kir_kenix]

that is some wicked mpg in your tacoma! really thinking what ur rig could do with sme aero-mods. im really suprised in the 6.6mpg gain, but some of that has got to come from ur driving and the conditions. keep up the testing and sharing results. looking forward to your next tank fill to validate those results. if you could avg 40 for a tank you will have achieved something almost unheard of in a non-diesal truck.

[aktacoma]

Originally Posted by kir_kenix

that is some wicked mpg in your tacoma! really thinking what ur rig could do with sme aero-mods. im really suprised in the 6.6mpg gain, but some of that has got to come from ur driving and the conditions. keep up the testing and sharing results. looking forward to your next tank fill to validate those results. if you could avg 40 for a tank you will have achieved something almost unheard of in a non-diesal truck.

I am driving from AK down to CO in mid September and that would probably when I am going to get the best mileage! I think I will really like P&G on trips because its like a game but I was looking at my calibration for the scan gauge and I screwed up my first fill because I didnt just click next when it asked how much fuel i used i put in 0 gal so I'll refill next time I go to town and then I can see what I was getting yesterday:/

[brucepick]

When I removed my power steering belt this past winter I did a different type of A/B test.

I read the gallons per hour at idle (fully warmed up) before and after removing the belt, using the MPGuino. I found somewhere just short of .02 GPH drop with the belt removed.

I did some math to extrapolate the savings when running the engine at highway speed. It came to a couple mpg in my case.

Basic concept of the calc: I estimated maybe .017 gph decrease in consumption at 670 rpm idle. This was from the mpguino. Highway speed is 4x that rpm so would need .017x 4 additional gal per hour to run the engine with ps belt.

Then from your mpg and your highway speed, you can find your gallons per one hours highway travel. Now add your additional gph to run the ps for an hour to your gallons for one hour's highway drive. Recalculate the mpg from miles/gallons and you can see the savings.

[aktacoma]

sounds like a pain in the butt haha I will just leave it off because i know that not having the parastatic loss is helping me same thing with my e-fan as long as I see results and it doesnt effect me that much I dont care how much one single thing is helping me

[MetroMPG]

Originally Posted by aktacoma

faulty results because the avg kept going up as i tested however scan gauge read same temp the whole time so i know its warm enough..

How far / long had you driven before you started testing? I ask because until the entire drivetrain is up to stable operating temperature, efficiency will keep climbing, even after the engine/coolant temp has been at operating temp for some time.

I am in the middle of calibrating my scangauge II in between 1st and 2nd fill does this make any big difference on results?

Not really, since the main thing we're looking at in a test is the difference between numbers, not the specific numbers themselves. Even if it turns out your calibration is off, you should still be able to count on the relative readings to do a test.

[aktacoma]

actually now that you mention it my drivetrain probably wasn't that warm.. it was pretty hot out that day but you're right about the drivetrain I drove about 2 miles before i started testing and I doubt it was warm by then.. lately though I've been seeing around 35 mpg ave so I don't know what I am doing just right but it looks promising for my little truck! as far as the scangauge I put 1.735 gal in and it popped up with 1.7 so it was calibrated..