Nissan 370Z Tech Forums banner
1 - 17 of 17 Posts

·
Registered
Joined
·
357 Posts
Discussion Starter · #1 ·
does a 3.91 final drive gearset install void the powertrain warranty?

is the boost in performance noticable when driving
(i'm not looing 4 numbers, just want it to feel faster..) :shiftdrive:
 

·
Registered
Joined
·
1,652 Posts
I've got 3.91's in my Z (http://www.350evo.com).

Parts & install about $1200.

Feels to me like 30-40 hp. :irock:

Significant improvement.
 

·
Registered
Joined
·
119 Posts
I've got 3.91's in my Z (http://www.350evo.com).

Parts & install about $1200.

Feels to me like 30-40 hp. :irock:

Significant improvement.
Is there a sacrifice? Are you loosing highend speed? Does your gas mileage fall off? Does first gear become useless for daily drive?
 

·
Registered
Joined
·
1,652 Posts
I haven't checked the mileage.

I still use first gear unless I'm slowly rolling at a stop sign.

RPM"s appear to be around 350 higher in top gear.

So - I don't see any downside.
 

·
Premium Member
Joined
·
6,474 Posts
no way is 1st gear useless... "they" were saying useless with FI. But it's up to your preference. Less load will hurt spool time however. How much isn't going to hurt that bad. I own turbocharged cars with a 4.2 final drive and let's just say they rip. Even if 1st gear was "worthless".. you don't really stay in first gear much anyway. If you do any sort of track work, you'll love it.

1-2mpg less. It's a 10% reduction.

top speed you can only go ~162 afterwards...
 

·
Registered
Joined
·
199 Posts
Call Adam at Z-1 Performance and he will make sure you get what you need to swap the fianl drive. Price and service what more can you ask for? Also as he recomended to me get the finned final drive cover to set off a nice mod!
 

·
Premium Member
Joined
·
6,474 Posts
Call Adam at Z-1 Performance and he will make sure you get what you need to swap the fianl drive. Price and service what more can you ask for? Also as he recomended to me get the finned final drive cover to set off a nice mod!

Yep, the Nismo diff cover is a great and cheap addition.
 
1 - 17 of 17 Posts
Top