25% increase in MPG (1 Viewer)

[imabigbangkindaguy]

Try a tank at 55mph and see what it does. I drove that all last week in Eastern Oregon and went from 19mpg to 22mpg over 2300 miles. I wouldn't be surprised if you can get it to 15.[/QUOTE]



Yep, The best I ever see, is when I just roll at 55 mph all day. Makes an incredible difference in fuel economy... just not alot of fun...

 

[PabloCruise]

What do get around town and what did you do to get it "set up right?"

And when I say very pleased, I mean power.

Mileage, I don't have high expectations of an Iron Pig rolling around with a tractor engine. If I want milegae, I'll drive my Civic!

 

[dwillmo]

My 62 gets right at 11 I guess around town. I only drive roughly 12 miles a day so it lasts me a long time, but the best I've ever gotten is around 235 miles on a tank. I recently took it to Houston. I got almost 350 miles on a tank. So driving at highway speeds makes a big difference in economy.

 

[slcfj62]

OK, I've gone through a couple more tanks of fuel, and I'm definitely getting around 12 mpg doing exactly the same kind of driving I was doing when I was getting 10mpg. I swear all I did was change the EGR valve along with it's modulator (still got 10 MPG on that tank) and then I replaced the PCV valve, and have been through 2 more tanks of fuel, getting 12 MPG on each tank. I'm strictly going by the odometer and not compensating for the 31 inch tires. Somewhere down the road I will send in my fuel injectors to be calibrated which is the last item on the FSM troubleshooting guide for poor fuel economy. But for now, I think I'm getting about what Toyota said to expect back when they sold this thing. I can't say I like 12 MPG, but is sure beats 10 MPG.

 

[Front Range 4x4]

I get 13.8 regularly on mine, if I do the stuff you did do you think I can get up to 16mpg?

 

[Slowerthanu]

I'm getting 13 with mixed driving on the same tire size and suspension (uncorrected).

It is the norm and probably means that your engine is running well. Also, at a shown 65, you are traveling at 69.8.

So, a 200 mile tank is actually around 214-215.

Dan

 

[silicon_toad2000]

HarryV, nice to see another ecomodder.

I'd say it was the EGR valve.
My understanding of what the EGR valve does (someone please correct me if I am wrong) is it reintroduces exhaust gas into the combustion chamber on coasting/cruising.
Exhaust gasses should be reasonably inert, containing very little (if any) oxygen or fuel and so won't have any effect on the mixtures in the combustion chamber.
So when you are coasting or cruising, the combustion chambers will fill with a portion of exhaust gasses and a portion or air/fuel mix meaning slightly less air/fuel mix is needed to fill the chamber.
This will then result in less vacuum (this is where I get a bit sketchy on the details) in the manifold, sucking less fuel, thus leaning out the mixture a little.
The extra exhaust gas in the chamber negates the bad heat/burnt valve effect normally associated with running lean.
I beleive it has a smiliar effect to chryslers Electronic lean burn.

 

[haryv]

egrs function

The EGR function is to reduce NOX or oxides of nitrogen. Basically, NOX is produced when the cylinder temperatures exceed a curtain point and a chemical reaction occurs within the the cylinders. Nox when exposed to sunlight, creates smog. Not a healthy thing to breath in. EGR only come on when the egr water temp switch opens up at a curtain engine temperature.

That's why I discourage anyone to just keep there egr on so I can see the mountains and breath clean air!

 

[Granite Grinder]

Doesn't the "cat" help to remove NOX?

 

[lehiguy]

I get 15 pretty much all the time now with SOA wand 35" BFGs and a recently rebuilt (and fairly pissed off) 350 that makes at least that much HP. If I were to drive the speed limit on the freeway it might get better, but 80 feels so good...

 

[Lugal]

lehiguy: showoff.

JK.

Anyhow, I've been getting just shy of 16mpg consistently in my 60 since we went off of winter blend this past spring. Before that, I was getting only 12-14, but I don't know if it's due to the different gas or due to the vacuum gauge that I installed in my cab around that time. Keeping an eye on the gauge makes me drive even more like someone's grandma, but it helps remind me not to stomp on the gas too hard unless I need to.

FWIW, I'm mostly driving around 45mph on somewhat hilly two lane suburban/country roads and still have stock tires. The timing is set with a vacuum gauge, so it's a bit advanced over stock, and I get 20-21 in Hg at idle when warm. I did take one road trip with a couple hours of 65mph highway driving in May, and got the same mileage.

 

[Western Omelette]

Just curious, how do you set timing with a vacuum gauge?

 

[Lugal]

Western Omelette-

Basically, like you would w/ a timing light, but instead of lining up the bb to the mark, you turn the distributor until you get the maximum steady vacuum reading possible. Then you back off a bit to avoid pinging under load. Kind of old school/hillbilly, but it's a good quick-and-dirty way to set the ignition timing.

 

[Western Omelette]

Interesting. I bought a cheap timing light to check/adjust my timing after failing CA smog test couple times High NOX. I'm interested in checking the vacuum method against the timing light/BB just to see where it outs me. Also trying to solve EGR issues.

Sometimes the hillbilly way is the best way! ...Sometimes

 

[Spook50]

Western Omelette-

Basically, like you would w/ a timing light, but instead of lining up the bb to the mark, you turn the distributor until you get the maximum steady vacuum reading possible. Then you back off a bit to avoid pinging under load. Kind of old school/hillbilly, but it's a good quick-and-dirty way to set the ignition timing.

I tried this before. Still got pinging and ended up right back where I started. OTOH I had a TON of carbon come out when I Seafoam'd my engine a month or two later. Plus now that I have a catch can in my PCV to prevent buildup in the intake and combustion chambers, I'm curious to try it again.

I assume this is done at idle while going off of manifold vacuum. This was how I did it.

 

[Lugal]

Spook-

Yeah, at idle, with the vacuum advance lines plugged, going off manifold vacuum.

A bit of a thread hijack now, but your experience w/ this is different than mine, so I'm interested in figuring out why. Maybe it's a difference in our elevations--I'm at around 450ft.--or maybe it's the difference between your 3FE and my 2F (most likely, I'd guess). I ended up a few degrees advanced (probably about 10 degrees, but I can't tell for sure w/ my cheap-o timing light), so I wonder why we'd get such different results. Any ideas?

 

[Spook50]

Spook-

Yeah, at idle, with the vacuum advance lines plugged, going off manifold vacuum.

A bit of a thread hijack now, but your experience w/ this is different than mine, so I'm interested in figuring out why. Maybe it's a difference in our elevations--I'm at around 450ft.--or maybe it's the difference between your 3FE and my 2F (most likely, I'd guess). I ended up a few degrees advanced (probably about 10 degrees, but I can't tell for sure w/ my cheap-o timing light), so I wonder why we'd get such different results. Any ideas?

Where my house is I'm at 2347ft ASL, but when I adjusted my timing before was at my parents' house, which sits at 387 ASL. So that's pretty close to where you were. My first guess is just the amount of carbon buildup in my combustion chambers. I'm going to give it another try in the next few days and see where it gets me. Be nice to get a touch better performance if I can, without pinging.

 

[Spook50]

Well I got around to playing with my timing again today. With the engine hot, at idle and reading manifold vacuum I was showing 16 in vacuum. I was able to turn the distributor until it got up to 20 in before I stopped. I set it so that it stayed consistent at 17 in, just so I'd have an incremental measurement to go off of. Drove it around the hill here a bit and took some inclines so I could really listen good and no pinging whatsoever. It also felt considerably more powerful just with that small advance. This could also be from eliminating all but three of the 3mm vacuum lines from my engine (due to the desmog) and replacing the remaining ones with silicon lines (I'll be sure to take a couple pics and update my thread accordingly as well). I'll leave it as-is for a little while and drive it around, then work on going up bit by bit until I notice pinging. Curious to see where I end up when it's as high as it'll go without pinging.

 

[dorcom]

I have ran low grade fuel in my 60 since I got it and a month ago I put premium grade in for fun I got almost double the miles out of that tank then I did running low grade so I have switch to 91

Nonsense! The energy value is the same regualr or premium! The difference is a higher octane rating (knock resistance). In the old days it was "Lead".

Tetraethyl lead

Gasoline, when used in high-compression internal combustion engines, has a tendency to autoignite (detonate) causing damaging "engine knocking" (also called "pinging" or "pinking") noise. Early research into this effect was led by A.H. Gibson and Harry Ricardo in England and Thomas Midgley and Thomas Boyd in the United States. The discovery that lead additives modified this behavior led to the widespread adoption of their use in the 1920s, and therefore more powerful, higher compression engines.
lead".

Octane rating

For more details on this topic, see octane rating.
Internal combustion engines are designed to burn gasoline in a controlled process called deflagration. But in some cases, gasoline can also combust abnormally by detonation, which wastes energy and can damage the engine. This phenomenon is often referred to as engine knocking. One way to reduce detonation is to increase the gasoline's resistance to autoignition, which is expressed by its octane rating.

 

[Wile E Coyote]

You bumped a 14 month-old thread to play Cliff Claven?? Bored much?