[serdet]

It is interesting to note that power is marginally reduced operating lean of peak, but the benefits are much, much lower fuel flows (rich, I'll run 15gph, lean, 10.3gph) and cooler cylinders- as well as not having to wash the soot off the bottom of the plane as often, as lean of peak produces a much more complete combustion.


If you are running leaner a/f ratios how are the cylinders cooler? maybe the physics of combustion are different in airplanes at altitude but automobiles the same can't be said.. Ive always been taught that fuel has a certain thermal effect inside a combustion chamber the more fuel the cooler the egt the less fuel the more egt.. cylinder pressure has a great effect on these theories also.

[WRXedUSA]

Did my first "long" roadtrip with the Scangauge. Went out for the PPIHC. My best mileage was from North Platte to Manitou Springs, CO at 330 miles on a tank. That was full rear diff, 3 people in the car, full trunk of luggage, 74mph, 2600rpmish, no wind, upper 90'sF and uphill on cruise control with some Denver-CoS traffic. It broke out to be 27mpgish. I have the 3% correction factor to account for the OD of the Falken 245/45s. Using Cenex and Sinclair 91.

And, that wasnt even trying. I found that you can stay well safe behind (or wake draft) semis and pick up 4mpg at speed. May not sound alot, but it does make a difference on your gas stopping points on multi-hour "IronAss 500" runs.

I noticed that traffic in general is moving a hellluva lot slower nowdays. Most trucks were doing 70 and under. I got passed by few cars doing 1mph below the speed limit.

I havent figured out how to use all the trip functions on it, but it does help you out finding that 'sweet spot' in fuel consumption.

[sujak]

I found out driving less is the best way to save gas , i havent filled up in two weeks. But really people need to get to work, just need to change your habits just because gas prices went down last week or this week doesn't mean they will stay down.

I average 22mpg with about 90%city/10% "highway" (roads are said 55mpg) I call that good gas mileage.

[blindfold]

I found out that 850cc injectors are not helping, regardless of your driving style the little F****ers are spraying fuel like no tomorrow

[NSFW]

Originally Posted by blindfold

I found out that 850cc injectors are not helping, regardless of your driving style the little F****ers are spraying fuel like no tomorrow

The engine is still pumping the same amount of air as before the injectors were installed. If the injectors are dumping fuel, your tune is bad and your AFRs are way rich. I'm guessing your latency or scaling is off. I put 816s in my LGT a little while ago and mileage took a hit at first but I got them dialed in and my mileage is normal now.

Consider downloading this tool...
RomRaider • View topic - Learning View tool
...and see if your fuel trims are way off. Read the thread and you'll see what I mean.

[fade`]

Originally Posted by TorstenW

...advance the timing via the constant boost @ 2600 rpm method, and run 87 octane, but just stay out of real boost

i can almost guarantee your car hates you and pulls timing like no other... i get saving money on gas but i'm pretty sure thats harming your engine

[blindfold]

Originally Posted by NSFW

The engine is still pumping the same amount of air as before the injectors were installed. If the injectors are dumping fuel, your tune is bad and your AFRs are way rich. I'm guessing your latency or scaling is off. I put 816s in my LGT a little while ago and mileage took a hit at first but I got them dialed in and my mileage is normal now.

Consider downloading this tool...
RomRaider • View topic - Learning View tool
...and see if your fuel trims are way off. Read the thread and you'll see what I mean.

thanks for that useful tool.

You are correct that the engine is pumping the same amount of air however I also moved onto a bigger turbo, so bigger injectors do spray more fuel since bigger turbos move more air. You are 100% correct that it is not just the injectors at fault.

by the way, are you still running the stock turbo on your LGT?


EDIT: pointed out by neverendingmods, I am indeed running a smaller tire combo, 235/40/17, so that isn't helping either as one need to shift more and rpms are higher, effective gearing being shortened

[NSFW]

Yes, still stock. Haven't decided which turbo yet.

[neverendingmods]

I haven't seen a bit of difference from stock to stage 2 catless ots cobb map to now protuned stage2 ewg+ tgv delete. I'm lucky to get 250 miles to a full tank of gas before the light comes on. This is stop and go driving normal. Meaning NO 50+ miles of highway at a time(it would help) and ocassional aggressive pulls here and there. I honestly believe I may be able to see 300-330 miles to a tank if I only did highway driving. I need to do a road trip this summer. As mentioned earlier in this thread, aero drag reduction(like no hood scoop or wings) and massive weight reduction might net you 5 mpg if you have a well taken care of car already. If you do mostly long highway trips to/from work, a much taller tire will help increase mpg as it will lower your rpm's at a given speed. If all you do is city, than a shorter tire will gear you to accel quicker and require less pedal to get you moving up to speed.
I'm surprised nobody has talked about aftermarket wheel bearings. In the motorcycle world, ceramic coated wheel bearings are all the rage. It's like the difference in a kmart skateboard and a Hawk board(the wheel bearings) or the difference in a journal bearing turbo and a bb bearing turbo in relation to how easy the blades spin and how long. The ceramic wheel bearings require more frequent replacing but the noticable hum when worn lets you know when.

[Seetz]

So, after about three days of casually reading this thread one of the popular reasons for why our cars use so much gas is that they don't have enough time due to high RPMs to fully ignite all the fuel in the chamber (for an in-depth explanation read pages like 7-15 should be somewhere in there). This and that there may be poor atomization.

This brings me to my question... Acetone? Supposidly a few ounces of Acetone (just went to the local paint store and it is $10 for 1 Quart) per ~10gallons of gas will yield better vaporization creating 1) more power and 2) less fuel being wasted out the exhaust (atomized fuel obviously not as liquid).

On a kind of side topic is it reasonable to run Meth Injection while adding x ounces of Acetone directly to your fuel tank?

Edit: For the record I am not concerned with the MPG of our cars but this thread has a lot of great info on physics and engine mechanics.

[sujak]

Originally Posted by Seetz

So, after about three days of casually reading this thread one of the popular reasons for why our cars use so much gas is that they don't have enough time due to high RPMs to fully ignite all the fuel in the chamber. This and that there may be poor atomization.

This brings me to my question... Acetone? Supposidly a few ounces of Acetone (just went to the local paint store and it is $10 for 1 Quart) per ~10gallons of gas will yield better vaporization creating 1) more power and 2) less fuel being wasted out the exhaust (atomized fuel obviously not as liquid).

On a kind of side topic is it reasonable to run Meth Injection while adding x ounces of Acetone directly to your fuel tank?

Edit: For the record I am not concerned with the MPG of our cars but this thread has a lot of great info on physics and engine mechanics.

Acetone and Mothballs use to work back in the day, but gasoline is much more refined today then it was in the 60's or 70's

[Seetz]

So thats the final word on that? Acetone just doesnt do anything anymore?

Are there any other known forms of fuel additives that will help the fuel ignite more completely?

Meth injection?

[dustybottoms]

Let's keep this conversation alive- I'm sure some of you guys (and gals) have some innovative ideas for reducing specific fuel consumption...

[RichXKU]

Originally Posted by Seetz

So thats the final word on that? Acetone just doesnt do anything anymore?

Are there any other known forms of fuel additives that will help the fuel ignite more completely?

Meth injection?

Nope, there is nothing you can add or change that will improve fuel economy without changing your driving style.
The best thing you can do is to avoid gas with ethanol.

My experiment is pretty much over. My past 3 tanks were:
29.0, 30.1, 29.6 MPG
I got 403 miles out of that 30.1 MPG tank.

[nhat]

Originally Posted by RichXKU

Nope, there is nothing you can add or change that will improve fuel economy without changing your driving style.
The best thing you can do is to avoid gas with ethanol.

My experiment is pretty much over. My past 3 tanks were:
29.0, 30.1, 29.6 MPG
I got 403 miles out of that 30.1 MPG tank.

windows up & ac on?