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Discussion Starter #1
Today I filled up my tank and after doing some math in my head, I came up with about 20 mpg. This gas mileage really hurts the wallet and it sucks. Why does the 2jz-ge consume so much gas? If the cause is the engine running too rich, then can't we lean it out some to get a little better gas mileage along with a slight increase in performance? When the corvette z06's gas mileage with a supercharged v8 is getting better mileage(on hwy), then you know something is wrong when an inline 6 isn't getting as good mileage.
 

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I'm getting about 21 MPG and I drive like an old man 75% of the time.

I recently got around 25 MPG on a freeway trip with the AC running the whole time.

Winter should produce better numbers......not by much though.

One of the faults of driving this head turning car is the gas costs.... beyond and intake and exhaust isn't much you can do to help these numbers.... We're all in the same boat.
 

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I'm getting pretty good gas mileage...most of it is highway...but I average about 25-27 mpg...its great...the only time I dip is when I'm driving at 120 MPH :lol:
 

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I was getting about ~400 per tank.

I think I'm going to be getting 250-300 now. :-?












O who cares...vrooooom pssssssssssssst 8)
 

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I fill up with premium gas and I'm still having to fill up about twice a week :(, but I also do about 130 on I-95 :lol:
 

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Yup this car sucks on gas. I get an average of 17 mpg w/ a combination of freeway and city in southern cali. I always have the ac on, so i'm not quite sure how much that would effect gas mileage. Recently I took a trip to vegas and got about 325 miles for one tank. I was still at a 1/4 so I knew I could have gone more. I get so jealous when I hear people post up an average of 23/24 miles per gallon. Also, for the people who average the 23/24 mpg, do you guys have ac on?
 

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1) 3L Engine
2) Gear Ratio(s)
3) Poor driving habbits (speed/acceleration)
4) Auto Tranny (more drivetrain loss than manual)

BTW, It has been discussed many times over.
The SRT HFI kit will make 1-2 MPG increase. It leans out the engine a bit for optimized performance with the intake.
 

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It's mostly the overall gearing. My IS turns over 500 RPM higher than my Firebird at the same highway speeds. Both cars get about the same highway milleage, but the Firebird is a 5.7 V-8.
 

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if you guys live in polluted areas, things like ethanol may reduce the pollution, but they also reduce your mileage. If you burn a gallon of ethanol and a gallon of gasoline there is more energy from the combustion of gasoline than ethanol, so you have to burn more of the ethanol to get the same amount of energy as burning the gasoline.

That can explain the discrepancies as to why some people get 24-26 while others get 17-20. Main reason is the engine just isn't very fuel efficient.
 

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we could all always go sell our cars and buy Toyota Prius :lol: :lol: :lol:
 

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Discussion Starter #14
vlad_a said:
1) 3L Engine
2) Gear Ratio(s)
3) Poor driving habbits (speed/acceleration)
4) Auto Tranny (more drivetrain loss than manual)

BTW, It has been discussed many times over.
The SRT HFI kit will make 1-2 MPG increase. It leans out the engine a bit for optimized performance with the intake.
I can see how the gear ratio can be affecting the gas mileage. Half the time from a stop, my car accelerates in second or third and that uses more engine power and burns more gas.
 

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Final drive ratio is the problem. IS300 spins 1200rpm higher at highway speeds than my 2001 Acura CL-S.
Dan
 

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Discussion Starter #18
webmaster said:
lexusaltezza said:
perfektrtw said:
The Z06 is N/A, not SC'd. :wink:
Actually the z06 is superchared. Trust me! :wink:
Um, you may have seen a supercharged Z06, but they do not come that way from the factory.
I apologize, both of you are right. I just looked it up. The reason I thought it was supercharged was because I rode in a friends z06 and the power was insane! He claimed it came with a supercharged, and I wasn't sure of that, until he pointed out a psi guage. When I saw that, I was a firm believer it came supercharged. However, the psi gauge might have been for something else.
 

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technically that makes you wrong but whos keeping track :lol:

lexusaltezza said:
webmaster said:
lexusaltezza said:
perfektrtw said:
The Z06 is N/A, not SC'd. :wink:
Actually the z06 is superchared. Trust me! :wink:
Um, you may have seen a supercharged Z06, but they do not come that way from the factory.
I apologize, both of you are right. I just looked it up. The reason I thought it was supercharged was because I rode in a friends z06 and the power was insane! He claimed it came with a supercharged, and I wasn't sure of that, until he pointed out a psi guage. When I saw that, I was a firm believer it came supercharged. However, the psi gauge might have been for something else.
 

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so what does that mean for turbo is300 drivers? very poor gas milage? any turbo guys in here? what kinda gas milage ru guys getting?
 
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