Hi, everybody!

i was just wondering how this would perform as a daily driver, and what are the differences between the 3.9 and the 4.0. Before you rip my head off, ive searched every thread related to this on g35driver and other various websites with very vague and limited information. Maybe someone who actually has one of these final drive modifications could give me their thoughts on what they like, and dont like, about the 2 final drives mentioned above any help at this point would be greatly appreciated. I would like the car to be very quick on accelleration while keeping it naturally asperated, and if possible still travel normally at highway speeds!?

 

^ In for an answer

 

i just installed a 4.10 gear set up in mine with a quaife helical diff. I kept my standard diff incase i plan to make a long trip. I figured i would be swapping often but have yet to put the stocker back in. There is notice in gas milage and freeway driving but i absolutely love it. As far as gear whine and stuff? its there but not real loud on mine. I run hks hipower/testpipes, so i guess it drones out. Talk soon mike

 

+1 on a answer

 

Impossible. With the shorter gears, your gas mileage will suffer and you'll be cruising at higher RPM's than normal.

 

given that gas is 4.25 a gallon, that 4.083 is really gonna hurt you at the pump.

 

I have 4.08's and it's not that bad, totally daily drivable. Gas mileage and top speed will suffer slightly (very slightly depending on your driving style) due to increased rpm's at cruising speeds as mentioned above. As long as you're not constantly going WOT and launching at every light, the gas mileage difference is not horrible. As for the top speed issue, how often are you maxing out the car's top speed on the street? Even on the track I have a hard time hitting 155+, so again, it's probably not going to be a huge issue.

The performance off the line is awesome, and acceleration is much improved. Keep in mind that my engine is built and I rev and shift higher (8500 rpm is where power stops) than a stock VQ, so I have about 1500 more rpm's for the gears to use, and they suit my car well. While I'm not trying to detour you, for a less built engine, 3.7 gears may be a better choice all around.

Also, if you get an LSD, that will add to the noise and roughness of ride (depending on the brand of LSD and initial lockup settings of course). I have a Nismo LSD, and it's very loud at low speeds and I would not recommend it for a daily driver. As far as the difference between the 3.9 and 4.08 gears, the difference in the gear ratio is so slight that it is mainly a difference in the price if I remember correctly. The 4.08 are Nissan OEM gears and cost less than the after market 3.9 gears - that was why I went with the 4.08's.

 

thanks for your help everyone!!, you guys with the final drive, will i be able to hit 200km/h? yeah i know its so fuc*ing crazy to drive fast, but i do, so, can i hit 200 still with the 4.089 FD