steve24:

I have no idea what is happeneing to the MPG of most G35X drivers. But I do know that on highway driving where I routinely flog my car up to 7000RPM in 2, 3, 4th gears, I have not gotten below 21MPG. On highway normal driving @ 70 - 80 miles per hour in 5th or 6th gear, I am getting an impressive 25 - 27 MPG. Sometimes, the gas needle doesn't even move---pretty impressive. Infiniti never told us that that the car could get better gas mileage than what was posted.

In city driving, when I flog the car routinely up to 7,000RPM, I experience a best of 17 MPG. Under normal city driving, I experience a best of 20 MPG. Of course, my car is moded out, and I use synthetic oil, so this maybe playing a role in the good gas mileage.

Jacko3 wrote:steve24:

I have no idea what is happeneing to the MPG of most G35X drivers. But I do know that on highway driving where I routinely flog my car up to 7000RPM in 2, 3, 4th gears, I have not gotten below 21MPG. On highway normal driving @ 70 - 80 miles per hour in 5th or 6th gear, I am getting an impressive 25 - 27 MPG. Sometimes, the gas needle doesn't even move---pretty impressive. Infiniti never told us that that the car could get better gas mileage than what was posted.

In city driving, when I flog the car routinely up to 7,000RPM, I experience a best of 17 MPG. Under normal city driving, I experience a best of 20 MPG. Of course, my car is moded out, and I use synthetic oil, so this maybe playing a role in the good gas mileage.

Have you tried our method of calculating MPGs instead of relying on your NAV?

Jacko3 wrote:steve24:

On highway normal driving @ 70 - 80 miles per hour in 5th or 6th gear, I am getting an impressive 25 - 27 MPG.

I think you answered the question yourself. You are able to shift into 6th gear with your manual, with the X, you are stuck at 3k rpms when cruising at 80mph which is a huge gas guzzler and needs to be revamped in upcoming models to maximize the overdrive gear.

The gearing on the X is not made for good gas mileage especially at highway speeds over 65mph.

Q45Tech and C-Kwik posted some interesting facts about gas mileage and gearing in this thread...

zerothread/331085

You might check it.

pits200 wrote:
I think you answered the question yourself. You are able to shift into 6th gear with your manual, with the X, you are stuck at 3k rpms when cruising at 80mph which is a huge gas guzzler and needs to be revamped in upcoming models to maximize the overdrive gear.

The gearing on the X is not made for good gas mileage especially at highway speeds over 65mph.

We are also stuck at 3k RPMS in the manuals @80. The final gears for the AT and MT are very close in ratio.

Most of us suspect that Jacko's readings are skewed by the NAV system since he refuses to do a manual calculation over hundreds of miles.

Sentientbydesign:

I don't know how Toolboothwilley who moved to Arizona calculated his MPG. but it was pretty close to mine.

Just hit 2k, and I get about 24 mpg. I got 19 once, but I was racing a friend home from work. I do about 65% freeway. I drive long distances to work, but I use the G throughout the day to get around. Work in Seattle, the traffic is awful. Even when there is no traffic, the stopping and going is ridiculous. I don't 'break-in' my cars like most people though. I don't go WOT for 600 miles, but I also don't baby it. It worked for my '07 Civic Si (I know, not a very popular car here, but I love Hondas too) and my Mazda CX-9. I got better performance that most and the gas mileage in my CX-9 is great compared to others that I've read about. I routinely get 22-25 mpg in it. A friend of mine told me to break in cars this way, gradual acceleration to go fast and such. He is involved in racing, both track and off-road. I know our cars and engines are not like those of race cars, but the logic behind it made sense. He just explained that you should drive the car hard from the start, but with some finesse. Just just mindlessly flooring it and constant revving in nuetral. I did a lot of research on it online and the 'break in' is not how it use to be. Some still believe it is necessary to baby it from the start up to a certain mileage. There is also evidence that suggest being too gentle on the car can cause problems down the road. I can't think of the websites I read, but if you google it you will get a great deal of debate about the topic. There were a ton of results when I did it. It has worked for me, and seeing the numbers posted by some of the other G owners, makes me believe it all the more. He told me performance would be better, as well as fuel economy. SOrry my text is being really wierd when I post lately. The alignment is funky.

*had to edit, late here and my post didn't make much sense at first, hope its a little more clear now

I just bought a used 2007 G35x with 24,000 miles on it. This car came tinted out and just looks amazing. However like you have noticed as well...it gets horrible gas mileage. I have been doing mostly city driving and I am getting about 12-14 MPG. Since Infiniti claims 18 MPG I thought there was something wrong with this car, maybe filters need to be changed, etc. Either way, those cars pulling up on the right of me trying to overtake me have a much harder time now.

You guys have to keep in mind that you are losing 2-3 MGP off the bat due to the fact that Ethynol is now in the gas. When they started putting Ethynol in I immediately went from 19 in the city to 16, where I have pretty much stayed for the last two years and I perform all maintenance like clock work so the loss has nothing to do with dirty filters or any of that stuff.

I get 16 MPG in normal driving. I tend to baby mine so I am not on the gas pedal hard except occasionally. I get about 26 MPG on the highway so I am satisfied.

Just my $0.02.

Goat_Wiz wrote:Just hit 2k, and I get about 24 mpg. I got 19 once, but I was racing a friend home from work. I do about 65% freeway. I drive long distances to work, but I use the G throughout the day to get around. Work in Seattle, the traffic is awful. Even when there is no traffic, the stopping and going is ridiculous. I don't 'break-in' my cars like most people though. I don't go WOT for 600 miles, but I also don't baby it. It worked for my '07 Civic Si (I know, not a very popular car here, but I love Hondas too) and my Mazda CX-9. I got better performance that most and the gas mileage in my CX-9 is great compared to others that I've read about. I routinely get 22-25 mpg in it. A friend of mine told me to break in cars this way, gradual acceleration to go fast and such. He is involved in racing, both track and off-road. I know our cars and engines are not like those of race cars, but the logic behind it made sense. He just explained that you should drive the car hard from the start, but with some finesse. Just just mindlessly flooring it and constant revving in nuetral. I did a lot of research on it online and the 'break in' is not how it use to be. Some still believe it is necessary to baby it from the start up to a certain mileage. There is also evidence that suggest being too gentle on the car can cause problems down the road. I can't think of the websites I read, but if you google it you will get a great deal of debate about the topic. There were a ton of results when I did it. It has worked for me, and seeing the numbers posted by some of the other G owners, makes me believe it all the more. He told me performance would be better, as well as fuel economy. SOrry my text is being really wierd when I post lately. The alignment is funky.

*had to edit, late here and my post didn't make much sense at first, hope its a little more clear now

IIRC, the break in period for the Gs is like 1500 miles and the two requirements are that you don't rev past 4k RPMs and you don't keep the engine at the same RPM for long durations (the engine needs to be sped up and slowed down).

The logic involved is too great for me to consider pushing the car off the lot.

I noticed that the rpm's on this car going 55 are different than any other. Maybe this means that they set different gear ratios or something? but overall, i get 15 mpg and about 200 miles to the tank.

Holy ****. You should get that checked.

Goat_Wiz:

Thank you for your fantastic write up. I have been pleading with tons of people on this forum to go out and flog their G-35. I have been flogging mine form day one and the engine is as crisp and sound as ever, and the transmission shifts like a perfect package of steel. In fact, my engine is now ready for a supercharger, the moment I get the money to buy one.

I have also been saying it here on this forum that the G-35 rides better when it is being flogged than when it is babied. In fact, the car's response has improved so much so, that i really wonder if I need a grounding gear anymore. Because of this, I am beginning to walk away from grounding gears and instead I am setting my sight on a test pipe.

Jacko,

Please don't get a test pipe. It's bad for the environment and tests have shown near no gains over a hi-flow cat.

Sentient:

I agree! Actually I called Stillen right after my remark, and they said the test pipes would not work for my car. I was told the High flow cats was all the 2007 G-35 Coupe could handle comfortably. So, I am done with test pipes. I guess, the only power adder left for me is the Supercharger. I dream about this all day. I wish I could win a lottery so that i can buy one tomorrow.

I have seen the promised land, and i will get there.

I don't remember you posting in the careers thread. What do you do?

As for the G35x getting bad gas mileage. It has a lot to do with your driving style and the fact that there are two differentials.

It doesn't matter x or s it is pretty close. My wife drove my G for this week. I needed more cargo so we switched. She ended up with over 20 mpg. I was curios about what's she'll get so I filled it up a night before I gave here and filled it up after I got the g back. That is pure city driving. Now you compare that to my 12-13 mpg hm....I love my G.

zozo

Sentientbydesign wrote:Jacko,

Please don't get a test pipe. It's bad for the environment and tests have shown near no gains over a hi-flow cat.

To heck w/the environment, have you ever been in a car with straight pipes? OMG

No. I've just been next to them. The gains between a hi-flow cat and straight pipes are going to be extremely minimal.

If my memory serves me correctly, we have dual cats, not just a single. As such the flow restriction is minimal when hi-flows are added.