Just getting everyone up to date....
The 3.9 final drives are scheduled to be in the shop the week of July 19th-23rd.
They should be shipping out the following week ............as long as the ring gear bolt pattern is correct this time!
Cheers

 

what is the oem gearing??

i have wanted to do this mod since the day i bought my car......

yippee!!?

 

3.5 on the 6spd.

 

how will this affect perfomance dwnshift....thanks

 

This would be a swap for the stock gears... no housing change?

 

Great for road race and tracking events. Improveded acceleration that you can seriously feel. I had this in my street car before it left for reverse engineering. I miss a ton.......but its coming back.

Correct .ring gear and pinion gear that we had made to fit in the 350Z/G35 pumpkin and diff.
Doing a diff with the install is recomended since the diff has to be removed for the ring gear.

 

Any experience commuting/freeway/street driving when you had this gear set installed? How does it affect the daily driveability?
Mika

 

Its fine for everyday drivng........just more smiles an hour!

 

What about speedo correction? Any plans?

 

Thanks.
What do you mean by this:
"Doing a diff with the install is recomended since the diff has to be removed for the ring gear."
Do you mean upgrading to a Nismo LSD or something?
Mika

 

I've heard that the Speedo sensor is attached to the wheels, so changing gearing will have no affect on the speedometer.
Mika

 

what type of power gains are we going to see off this?...how much is an install going to be?....how much are these gears going to lower our top speed...and finally...knowing that my friend changed his stock mustang gt gears to 3.73's and then had to get a chip to recailbrate his speedo...then blew his tranny. what are the chances of this messing up the Z? thanks

 

cannot wait!

 

The 350Z speedo is calculated by the 4 wheel speed sensors. One on each front wheel and two that read off of the inner axle flanges. By changing the Final drive ...........IT WILL NOT EFFECT THE SPEEDO READING.

There is no gain in hp per say...just better and faster acceleration......
ITs great time to upgrade to a Nismo diff because the diff is required to be removed for the final drive installation.

Cheers
BJ@350EVO.com

 

What if you decide to keep the stock diff, how will this affect the dirveability? I assume no difference?

 

There has been previous mention that this could affect the cruise control. Is this true? I know the speedo is not affected but was not sure how the cruise control system works. If it uses gear selection and rpms then it would be messed up, but if it only goes by speed then it should be ok???? Also, I know there are issues for automatic cars. What solution will there be for us? Can we have a pumpkin put together with final drive and LSD and then do a swap by sending our complete pumpkin in?? How much will this cost in the end?

 

Sorry for the noob question but what exactly would be the benefit of changing my differential?

 

stock viscous unit is ok for general street driving...start putting some good power down or doing lots of track days and you quickly find its barely up to task. Replacing the LSD in my car (I went with Cusco RS 1.5 way, which is adjustable to 2 way) one of the best mods I did.

 

so if you have the stock lsd will we have to change it? how bad is gas mileage after the install?

 

You dont have to replace it........but in general......the OEM diffs are terrible......allowing lots of inside wheel sping which means no power is bering put down t the ground. The Nismo diff is a great street and track diff.
During the installation of the 3.9 it is required that you have to remove whatever diff you have in car now to remove the old final drive. IF you have a new diff your killing 2 birds with one stone. You can then just bolt the new ring gear to your new diff. It will save on some of the install time.