yes it does affect performance but not enough for us to notice in our daily drives.

 

omg 240miles a tank??? Talk about a heavy foot...I thought my 350 a tank (til light comes on) was horrible, that's 90 less than what I get. Granted I am stock and low mileage at 20k.

 

I am having idling problems..i wonder when i clean my TB's in the spring i will get better MPG's?

 

I never drive till my gas light comes on, but from the remaining miles i get about 330 a fill up. this winter i am getting 280 or so, so if your getting 365 your car's doing really well....

 

i don't think i've ever gotten 300mpg. thats crazy. maybe something is wrong with my car (or foot). hehe

 

wait... the people who get 300+... what gas station do u use? how do you get 300+ do u have 5AT AWD?

When i try hard.... i dont rev past 2.7k rpm.... im going pretty slow...

 

I use all premium....

 

duh... gas (station) brand....looking for driving habits, i dont know how i can drive more conservative

 

365 would be phenomenal in my book. I avg 16.4 mpg and get anywhere from 280-320 a tank

 

i average 18.8-19. i try to take it easy except when im having fun, and then i really get into it. my highway cruise speeds are normally 80+ though... so that doesnt help. 70 just feels so slow in our cars and i would fall asleep!
ive only made it to 400 once, but i never let my tank get that empty anymore bc if i do the car wont let me put but a couple of gallons in. [stupid filler neck issue!]

 

365/tank is respectable. If you put 16.7-16.8gals in when you fill up, like i do, you are getting about 21.5mpg. If you have an automatic, that's pretty good for 07 G35. I get about 21.5mpg driving around town and 24mpg hwy driving 70-75mph. BUT, I have 6MT which helps a lot. I can short shift, skip gears, push in clutch and coast up to traffic lights or down long hills. I don't hypermile and shut my car off at traffic lights. i just drive normally and occasionally have some fun and get on the gas a bit.

In winter time i have noticed mileage drops off to 18.5-19.5 maybe 20mpg. I guess this is because until engine warms up, ECM runs a enriched fuel air mixture.

Best way to improve mileage I can think of is to put a taller final drive gear in differential. Then you are not doing 3000rpm at 75-76mph in 6th. This is why if you can drive 60-65, you will get better mileage, because your rpms will be less. Rpm's are high due to very short stock gearing, in 6MT anyway. This kills mileage. Taller gearing will reduce HP at rear wheels. I am ok to make this trade off. Car has plenty of HP but is a bit short on fuel economy compared to other vehicles in its class.

I have looked around for final drive gears but have found nothing in range I am looking for. Stock is about 3.7 what I would need to drop 500rpm's in top gear is about a 3.1. I found a 3.3 but that is not enough for my purposes. Plus a 3.1 final drive would make 1st gear not so rediculously short. I don't even use it when trolling around town, Usually I shift 2->4->6. I guesstimate with a 3.1 final drive, in a 6MT, I could probably achieve 27mpg fwy, maybe better. There appears to be no taller gearing options for these cars though, other than 3.3.

 

I am happy if I can get to 300 miles before the light comes on...

 

365 is my max, I have NEVER gotten 400 mil

 

So how about that 2011 cadillac cts-v? 12mpg w/ a 20 gallon tank... lol

 

I averaged 21.7 over an 800 mile road trip at Christmas. Avg speeds over 65 with PLENTY of spirited enthusiastic driving. My only mod is a Bully Dog GT tune w 2 degree timing advance.