Saving gas [Merged 3-8]

[EHeye]

Alright, our gas prices here locally have sky rocketed like there is no tommorrow. So I have a question, I dont make much money so I wanna save as much gas as possible.

Say im going up a hill about 7% upgrade and im doing about 80km/h (50mph?), in 5th gear to keep it constant im running at 2500rpm and 4-5psi boost, in 4th gear im at 3000rpm and 13inHg in Vaccum. Which one of these will give me better gas mileage, lower rpm in small boost or little bit higher rpm in vaccum.

 

[97GSTURBO]

Little higher rpm with no boost (vac) will give you better gas mileage. (not much though) :laugh:

The best way to save gas is to take your wastegate arm off the flapper arm and run no boost at all.

 

[KRAZYKOREAN]

Just don't drive haha.

 

[EHeye]

Can i get some proper answers, thank you Krazykorean, i dont appreciate that, i want to know what the answer is not have a comment like that, thanks.

I do believe the 4th gear at a little bit higher RPM is better cause if im not mistaken with our ECU's as soon as it goes into boost the ECU compensates and makes it run rich like a mofo.

 

[candela]

wow that was pretty funny...

 

[KRAZYKOREAN]

Hey no prob dood.. it was a joke. haha.. but anything you do unless you get a afc or something to lean the fuel out alittle.. other then that it won't make a huge difference of what gear. and how steep the hill is... Is that a better answer... if not then... whatever..

 

[candela]

yeah

 

[EHeye]

Originally posted by KRAZYKOREAN
Hey no prob dood.. it was a joke. haha.. but anything you do unless you get a afc or something to lean the fuel out alittle.. other then that it won't make a huge difference of what gear. and how steep the hill is... Is that a better answer... if not then... whatever..

if you read my first post, it says a 7% incline, what dont you understand out of that

 

[KRAZYKOREAN]

DOOD read my post I didn't ask you how steep the hill is I made a statement of...other then that it won't make a huge difference of what gear... and how steep the hill is..... I am not asking you ok... I read the first post...

 

[candela]

EHeye>Koean


W
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3
D

 

[EHeye]

wow, this post turned very useless fast, just wanted to know, on the basis as my car sits without adding a afc or anything, over a long period of time which would consume more gas 4th gear no boost 3000rpm or 5th gear 4-5psi 2500rpm. I drive this route everyday and I know it will make a difference in the long run. Just wanted to know, I apologize krazykorean.

 

[KRAZYKOREAN]

Originally posted by candela
EHeye>Koean


W
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3
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Humm let see its Korean not Koean

Spelling>Candela

 

[KRAZYKOREAN]

Dood regardless of vacumm... higher rpm equals more revolutions per min equals burning more fuel.. But like I said it will make close to nill on gas milleage.. because if you use lower rpm and boost. and then you have rpm and no boost its basillcay the same.. I Have been trying to say that.. I am just trying to help man..

 

[candela]

awww

= Korean

 

[nutshot]

If you find yer peak torque and the RPM that occurs at, you can use that range to recieve the most efficient power/mileage.

 

[EHeye]

Yah but what im saying is there has to be an equal medium as to which puts more fuel into the car, if im not mistaken does the ecu go into rich mode when hits boost, cause if you go into boost of course you are putting more fuel into the engine than running in vaccum.

 

[EHeye]

Time to bust out the manual and start doing the actual math of the equation, does anyone know how much fuel the car uses in lph when @ 4psi and 15 InHG

 

[EHeye]

OK I looked in my haynes manual and it says 26 to 28psi fuel pressure @ idle and fuel pump pressure maximum is 60psi

are these the numbers I should go off of and try and calculate this?

 

[candela]

you cant calculate it you dummy...give it a fuggin rest!!

 

[KRAZYKOREAN]

You are going to waste so much time....I bet you if you calculate.. which i won't think it will happen.. the results will be the same as i have been saying.. just a waste of time.. dood..But I am sick of the thread due to no one listening and realizing what people are saying.

 

[98TsiAWD]

Obviously you are gonna get the best gas mileage in 5th gear at the lowest RPM possible wiht no boost.

 

[EHeye]

yes 98TsiAWD, you would, but it is producing boost, going up a hill, if I had these two numbers I would be able to calculate it out, I know it sounds pretty lame, but I sorta wanna figure it out now, I have a lot of people stumped here at work about it and I just wanna get some numbers on it. Just cause you guys dont care, doesnt mean someone else here may not care. Its all about physics and w=f*d

 

[candela]

Well the reason you cant calculate it is because of all the factors that come into play. When you have mods done it changes every little thing. Maybe yoru fuel pump does put out a certain amount of fuel but you do not know what your duty cycles are do you? What if at the moment you think you can calculate it your fuel pump is only gettin 11.7 volts instead of 12.2... What if your airfilter is clogged, what if your fuel filter is dirty? There is no way you can calculate this because they are both prolly so close that the littlest thing will change it completely...so why dont you just drop it?

 

[13secGST]

leave the guy alone...he want to do something...so let him.

 

[crazyjoe]

Why not do this:

For one week, drive it in 5th.

For the next week, drive it in 4th.

Compare mileage.

Done.