Better Mpg

[twistedsymphony]

You know there are two sides to the tire inflation deal.

1- over inflated / highly inflated = less rolling resistance = better MPG
2- under inflated = smaller rolling diameter = better MPG

"Shifting into 4WD" by Harry Lewellyn make the claim that lower PSI = higher MPG.

Someone should run a test using LT tires. 40 PSI, 35 PSI and 30 PSI.

I'd do it, but I haven't driven my car in almost 4 weeks, so It'd take me a while to go through 3 tanks of gas I'm still on the tank of gas I filled up BEFORE I ran the trail with Todd, and Zeus.

Please keep us posted on your hydrogen findings.

Theoretically larger rolling diameter will increase highway MPG... the reason is because it changes the ratio of RPMs to tire rotations such that your engine doesn't need to spin as fast to go the same speed.

the down side is added weight which means it takes more energy to build momentum (eg: stop and go city traffic mileage would be worse).

Wider tires will suck down your MPG because the more contact area you've got the more rolling resistance exists, especially when turning.

consider that most people running 33s are also running 12.5" wide as well... the wider track and added weight will do more damage than the added diameter will help.

Proper alignment and proper inflation help too.

if you want the best mileage though you're looking at installing some wagon wheels on your VX

seriously though.. I've heard from more than one trooper owner that the 3.5L with factory gearing likes 265/70/R16s the best for MPG... moving to that size over the factory 245s was good for 1-2 MPG (that's a 5-10% increase right there)

By that metric consider that moving to higher octane may increase your mileage by 1-2 MPG would be more than enough to eat the extra cost of the fuel.

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Personally, I'm wondering how much damage the EGR valve is doing...

[SYNTHETICDARKNESS]

well all the stuff i did to get the mpg is in one of my post on here. i use distilled water and koh which adding koh makes amps in the gen, more koh more amps up to around 20 or so total using electrolysis. the scan gauge lets me check all my sens to see what they are running at and if they are doing what they are supposed to be, on top of that it let's me know my mpg as i drive which knowing that you can even increase your gas, kinda like a teacher showing you how to do it the right way i guess (poor example, but i'm tired). the gauge is worth it wether you have anything or not, knowing everything about your vehicle is priceless. the tire thing is pretty good also, but such a pain to experiment with. we've had the unit on the crv for about 3 months, then finally got our gauge, and after leaning it out we are about 60 avg. mpg. didn't lower the vx, probably not going to. gotta remember though about bigger tires slower speed, smaller tires faster speed, even though the speedometer will be off, in my opinion it takes more effort to move something bigger then something smaller, kinda like a underdrive pulley. we might buy a map sens enhancer so we can adjust rich to lean from inside the vehicle, makes it so much easier. i think i'm gonna pimp out the vx with 45" amish wheels lol.

[WormGod]

i think i'm gonna pimp out the vx with 45" amish wheels lol.

Mount a horse up to the front of the VX at that point and I can guarantee an even greater decrease in gas. The first ever "hay powered VX"!

[Ldub]

Mount a horse up to the front of the VX at that point and I can guarantee an even greater decrease in gas. The first ever "hay powered VX"!

LOL...I can see it now...

[WormGod]

LOL...I can see it now...

Only true if your VX really was an Amish tuner.

[VehiGAZ]

Good luck with your science project! I hope you don't explode!

I guess it's pretty obvious that I'm a skeptic when it comes to these hydrogen fuel enhancements. I just hope no one screws up their engines playing with explosive gasses. Insurance will most likely not cover a fire loss claim when they figure out that the owner installed a hydrogen generator on their engine.

[SYNTHETICDARKNESS]

nothing wrong with being a skeptic that's what we are so i know where your coming from, but hey what the h#ll can write it off for taxes on the irs website, and on top of that you get your own firecracker maker. still waiting for the sens still in mo.. so far the engine in the old ladies car is fine, checked throttle body no signs of anything nice and shinny, plus her vehicle is the test vehicle, couldn't do that to my poor vx now until i know for sure. i'm pretty safe from blowing up the bubbler keeps everything safe if it backfires, and if not i believe our ins co covers just about everything, but it's fun filling bags up to show people what it does, boy is it loud.

[circmand]

[QUOTE=twistedsymphony;133308]Theoretically larger rolling diameter will increase highway MPG... the reason is because it changes the ratio of RPMs to tire rotations such that your engine doesn't need to spin as fast to go the same speed.

the down side is added weight which means it takes more energy to build momentum (eg: stop and go city traffic mileage would be worse).


I get that but once you decide on the tire size it seems to me max inflation is the way to go because you get max diameter, minimum rolling resistance and the air dowsnt weigh anything. Or am I missing something?

[Riff Raff]

[QUOTE=circmand;133354]

Theoretically larger rolling diameter will increase highway MPG... the reason is because it changes the ratio of RPMs to tire rotations such that your engine doesn't need to spin as fast to go the same speed.

the down side is added weight which means it takes more energy to build momentum (eg: stop and go city traffic mileage would be worse).


I get that but once you decide on the tire size it seems to me max inflation is the way to go because you get max diameter, minimum rolling resistance and the air dowsnt weigh anything. Or am I missing something?

Basically, the added weight from oversize tires comes from the simple fact that there is more material rubber required to manufacture the bigger tire (more rubber material = more weight).

Remember, it takes "x" amount of energy (gasoline), to move "x" amount of weight (in this case wheel & tire). The ideal solution in gaining maximum MPG with tires & wheels is to run the "tallest" tire that will fit (maximum O.D. = lower engine RPMs for same speed); at the "max PSI" (per sidewall label = least rolling resistance); with the "narrowest" available tread (low section width = less drag); mounted on an all aluminum lightweight wheel like CenterLines (reduced wheel weight = reduced overall weight). Thus, having said that-- an example of the most "economical" tire & wheel combination to mount on the VX is the TOYO - Open Country A/T in 255/70R18 (32.1" O.D., only 10.3" wide, weighs only 41 lbs) and mounted on lightweight aluminum wheels (such as Centerlines).

[twistedsymphony]

you're right that more weight = bad

but there is a difference between weight added to the rotating elements of a vehicle (ie: wheels/tires/driveshaft/flywheel) and just adding weight to the vehicle overall.

obviously keeping the weight down will improve nearly every aspect of the vehicles performance... however when talking about weight in the drive train that weight dramatically effects acceleration... in most vehicles 1lb added to the drive train effects acceleration and deceleration as much as adding 10lbs to the overall vehicle weight. This obviously varies depending on the drive train but the point is that keeping the weight down in the wheels and tires is MORE important to performance/economy than just keeping it down.

That's not even talking about the benefits to handling characteristics. The suspension works better with a lower amount of "unsprung weight" (eg: the amount of weight on the rubbery side of the suspension mechanism).

It's all about momentum... it takes more effort to get heavier tires moving or stopping... be it rotating or bouncing up over a bump in the road....

It's why racers swap out their heavy flywheels and steel drive shafts for light weight aluminum versions... they might only save 50lbs to the overall vehicle weight, it doesn't add any hp or torque but it changes the acceleration characteristics as if they'd dropped nearly 500lbs off the total weight.

[SYNTHETICDARKNESS]

well we got the sens enhancer, got it all sodered on and went down the road for a little tuning, city driving around 45-55 then highways was around 60-70. had it a little to lean though when i first started stalled in my driveway, but after playing for a while i finally got all the controls where they are supposed to be, and no check engine lights saying to lean or anything now, and it runs normal with the hydrogen, but when we shut it off we don't have much power. we are still gonna take it and hook up an air/fuel gauge to make sure everything is reading were it should be for the safe side. i'm just friggen happy it works, wish we could get 100 mpg, but that will probably never happen. all we do have to do now is drive around and test, make sure everything holds good, and if it does, my little vx will have one. as for the tires everyone has there opinions about them, but mine i still think the smaller/lighter the easier, just like having two of the same vehicles one big wheels, and one small going a steady 65 then putting it in neutral and see what one stops first. to me the one with less friction will keep going, because there is less to stop. by the way do they make aluminum driveshafts and flywheels for the vx. likes to get me them if they do.

[taylorRichie]

Please keep me/us posted on your VX install... I'd really like to give it ago... especially if I can write off the reactor (link please)

As for Aluminum Driveshafts, I'm sure any place that makes custom driveshafts for race cars and off road performance can make them for you.

Thanks for keeping us up to date

[SYNTHETICDARKNESS]

that place where we bought ours is www.savefuel.ca, it took a couple weeks before we got it so just depending on how many people are ordering depends on how quick you get everything. we love that it's working so far, so as time goes on i will keep everyone up to date on the progress of everything. as for the flywheel and everything i'll have to see how many fingers i gotta cut off to have them custom made. you can go to the irs website and look at the write offs it's in there somewhere i think with hybrid vehicles or something. this would be easy to install on my vx with my intake could go right behind the drivers side headlight.

[taylorRichie]

Theoretically larger rolling diameter will increase highway MPG... {/snippit}

All of what you posted makes sense... Thanks

[don moore]

I dont get it(scratching head)....put water were? and W.T.H. is a KOH?
sorry Im dumb.