Need some suggestions…

Two weeks ago I traded in my old G20 5MT for the 03.5 G35 6MT, and I’ve been a happier man since. However, I am finding the transition from a 5MT to 6MT a bit unfamiliar. The suggested up-shift speeds listed in the owner’s manual are so conservative as to be impractical, so I’ve been shifting when the engine is at about 2500 to 3000 rpm (as I am still breaking in the car). Thus my questions are as follows:

1. What is the optimal rpm or up-shift speeds during breaking in?
2. What is the optimal rpm or up-shift speeds for best fuel economy?
3. Once broken in, what is the optimal rpm or up-shift speeds for quick acceleration (like launching a rocket off the pad)?

Appreciate all your collective wisdom on this one.

 

this is a simple one. before breaking in your car, dont shift past 4. everything below that is good and dandy. after break in, shift around 3-4. usually, i just go all the way to allmost redline, then shift. its so much more fun. but cops tend to look more at you...dangerous.

 

I'm an envious member of all of you here (I don't own a G35 - maybe someday!) but I do have a 6 speed Maxima. I've driven manual cars for over 10 years. With my Maxima (same basic engine as the G35 although the transmission is not nearly as good), I up shift at around 2500-3000 in normal driving. When I was breaking in my engine, I didn't go above 3000 rpm as much as I could. As far as best accleration...shift at the optimum torque/horsepower which is a little below redline I think. Best fuel economy would probably be the recommended shift points by Infiniti. I tried to shift at low rpms to see how much difference in gas mileage it would make as an experiment for one tank of gas. The results: 23 mpg when shifting normally; 24 mpg when shifting at low rpms. For that one mpg, I would rather enjoy the acceleration!

 

Thanks Yakuza, you confirmed my suspicion that low rpm shifting does not improve fuel economy enough to justify giving up the fun of fast acceleration.

 

3800 is the point where fuel usage goes up a lot. from the sound of the engine, i would say that he secondary intake channel opens here.

shfting at redline is a good place. our power drops off VERY quckly at about 6200 rpms, so if you can shift at 6500 or so that is good.

economy shifting there is none on a G, you get low 20's if you are driving like a bat out of hell or if you are cruising 75 on the interstate.

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