Nissan 370Z Forum - 4.08 Final drive

Nissan 370Z Forum (http://www.the370z.com/)

- Engine & Drivetrain (http://www.the370z.com/engine-drivetrain/)

- - 4.08 Final drive - feedback please (http://www.the370z.com/engine-drivetrain/35760-4-08-final-drive-feedback-please.html)

Quote:

Originally Posted by Z eliminator (Post 1090427)

My gas milage is in Canadian gals. Converted to US gal it would be 31.25 and it droped to 26.25 mpg.

Z

What about your RPMS at Highway speeds?

Is there any way to keep the cruise control on a AT? What if the swap out was just for the manual gears?

I have a g37 7at with 4.08's and my cruise control stays usually but sometimes it doesn't work (no idea). My 1st gear is 30mph, 2nd 45 mph and 3rd 60. I have to be at 3rd to get to 60 and was wondering if a 3.69 / 3.9 would be better suited and what each gear will take me to?

Not to get too far off subject. Can us 7A/T guys swap over to manual and have it bolt up or what would we need?

Thanks

Quote:

Originally Posted by Zat_Zuma (Post 1088608)

I found that the 4.08 gears are too much gear for the manual transmission drivers. The shifts between 1'st and 2'nd are so quick, I bounced off the rev limiter far too many times in first and second gears. :eek:

The SRM seemed to be out a few hundred RPM but either it has adapted or I'm use to it now as I barely notice it.

I've changed my rear diff to the 3.9 gearset from the 4.08 and hopefully this will make the 1'st and 2'nd shifting easier, SRM and less rev limiter bounces. :driving:

Time will tell.

I've been driving with the 3.9 gearset for a few miles now and found the difference between the 3.9 and 4.08 driveability much better. The SRM performs flawlessly and no real differences in rev matching. The acceleration is more linear with no bouncing off the rev limiter anymore.
I've noticed that normal street driving is now more in 4'th gear; 80 Km/h @ 3000 RPM; 60 km/h @ 2500 RPM; instead of using 5'th gear for street cruising. 120 km/h is 3000 RPM in 6'th gear and instant passing acceleration, when you need it. I am much more content with the 3.9 gearset, versus the 4.08's.

Just my 2 cents

Quote:

Originally Posted by L33T Z34 (Post 1214171)

I'm very content w/my Frontier 3.916 final too! Nissan part number 38100-0B66A.

Interesting, I didn't know there was a 3.9 option from nissan, I only saw an aftermarket gear that looked quite expensive. This might be on my list when I finally upgrade my LSD.

I love my 4.08s, they add great low end and liven the car up ....

I have absolutely no complaints with anything

^^ how about top end? Do 4.08 gears kill top end acceleration? like in the freeway

nope not at all, your rpm will be higher so it will act will help on freeway acceleration unless u cruise doing 150 lol

Quote:

Originally Posted by Z eliminator (Post 1087821)

The 4.08 's work great with my 7 AT. 1/8 mile in 8.01 seconds, the 1/4 in 12.42 @114.3. Im turning 6000 rpm in 5th.
The diference in rpm is aprox, 700 to 800 rpm more and fuel consuption goes from 37.5 to 31.5 mpg.
2nd gear is the gear of punishment as the car just screams. Now hold the gas and brake at 2200 rpm and launch the car . It becomes a cruise missle. I shift at 7800 to 7900 rpm.
3rd gear is also very powerful and fast.

Where did you get the gears?????

Quote:

Originally Posted by jdonadio (Post 1371850)

Where did you get the gears?????

Haven't you read the thread? It has the Nissan part#, just do a google search for that number and OEM Nissan parts or go to GTM's site.... jnaut also said he could get them, you could pm him too.

Quote:

Originally Posted by Methodical4u (Post 1372394)

Haven't you read the thread? It has the Nissan part#, just do a google search for that number and OEM Nissan parts or go to GTM's site.... jnaut also said he could get them, you could pm him too.

lolol

Trying to decide which final drive would be best. I have a bone stock 09 370 nismo, that i plan on boosting with the gtm TT kit. This kit alone will give me approx 500whp. However, i want to do gears first. Any thoughts on this Dilemma? Has anyone else did the 4.08 or the 3.90s with an FI setup?