This is my first impression of the best mod i have done to date... with the impending install of the Apexi Coilovers.

the 3.9 FD honestly should have come stock in all rev-up motors, its unbelievable the difference they make all throughout the rev range. with me revving to 7K , the car has a totally different feel, it has that grunt through the bottom on the rev range and the car accelerates much more freely.
Great mod for all rev-up allows you to actually take advantage of the power band provided in this motor, the FD is matched much better than stock to the motor.

i also had BJ throw on the portflow throttle body which didnt really seem to give me any power but did seem to give me better throttle response, i think id get more outta this with the aid of the UTEC.

Im goin to rate this a 9 in being the perfect mod for anyone with 1,000 to spare. It would be a 10 except the noise it makes, not a bad noise just loud enough to know its back there.
I wasnt around when 350evo install so i didnt get any pics but i did get hooked up with the Nismo diff cooling cover which is a nice lil bit of bling.

which also leads me to my next list of stealth mods before i go all out and turbo... JWT C/F, LSD, UTEC

ill keep it all posted and updated on future mods i install i am planning on doing a full writup on my suspension install so stay tuned campers!

 

Thanks...now you made me eat ramen for a while so I can save up for this! Gear changes are unbelievable...I put 4.10s in my GT and it was a totally different animal.

BTW...the new gears shouldnt make any more noise than the stock ons did

 

I am getting my 3.917 gears from 350evo installed next week. Can't wait. My car is an 03 6 speed with most of the bolt on NA mods. They were all listed in my signature which has now disappeared.

03 Daytona Blue 350Z MT
Injen CAI
Borla TD Exhaust
Crawford Plenum, Cats, Headers and Strut Bar
Nismo S-Tune Suspension, LMGT4 wheels, clutch and flywheel
StopTech BBK, 332mm front and 328mm rear
Technosquare ECU Reflash
Emerald City Z Club

 

its not the noise more of the whining from the way the backlash is set. but no conventional grinding kinda noise just a hum. but bj says its because of the above and how its set to run cooler.

 

MI 35th and others: from what I understand, this final drive is 10% shorter than stock...does that translate into the same reduction in max speed? Have you had the rev limiter changed/deleted in 6th at all?

 

It will reduce your maximum speed because the gearing is shorter, but who really cares if your car goes 145 instead of 155. How many times are you going to go that fast. Plus the shorter gearing will improve acceleration in all gears. I don't know about you, but I hardly use sixth gear now as it is. After the 3.917 ring and pinion gets installed next week maybe I will use it more.

Also my ECU reflash on the car did away with the speed limiter and increased the rev limiter to 7,200 rpms so I don't expect the new gears will make much difference in the top end on my car versus a stock 350Z.

 

If only I had a Manual Tranny...

 

I'm pretty sure the 3.9 final drive reduces the top speed to 155mph which is the limited top speed anyway. The gearing in our cars are set to hit about 170mph theoretically (not fully sure on the exact mph). So unless you have FI and the limiter taken off it doesnt't change the top speed.

 

thats what i was thinking too faris, its all theoretical im never gonna need to go above 155 in my car but ive been there a few times if needed.

 

SQ40: I will sell you my 3.5 gears to get the same effect with an Auto Tranny.

 

i was under the impression that the rev-up motor though has a higher top speed. around 160 with the rev limit and speed limiter near there.

 

yea forgot about the rev up motor. If the rev up motor is limited to a higher top speed then with the gears you'll "only" be able to hit around 155.

 

Great! All I need know is 850dollars!!!

 

Nice write up Glad to hear another positive response to the FD.

If I don't go FI, I will be going with the 3.9FD and LSD...

FYI... you can pick up the Central 20_FD for around $500.

Zquicksilver

 

No track record on the Central 20 3.9FD yet. Tony at Performance Nissan posted yesterday that the Central 20 unit may be from another production vehicle. The 350evo 3.9FD is track proven and built specifically for our cars.

Not trying to say that the Central 20 unit is not good quality, but not aware of anyone who has had one long enough to say. Also the 350ev0 3.9 comes with excellent instructions.

 

pm'd

 

Did the 3.9 Final drive reduce any top end acceleration at all? Like maybe 100mph+ acceleration? Because i heard everytime you put in shorter gears, it'll increase low speed acceleration, but you get into higher speeds, the car will acelerate a little bit slower. Dont know if this is tru tho, can somebody comment on this?

 

No that is not true, the car will accelerate faster in EVERY gear at all speeds...

 

the Central 20 is also made specifically for the Z

 

this may be just rumor and im not trying to down any products here this may actually help them out, but as i was told the a few 3.9FD were sold to JPN from 350evo, it was a belief that the central 20's FD is identical to the 350evo in EVERY aspect. not to say that this is true but its a probable cause why someone in JPN would decide to sell a 3.917 FD and not say a 4.0 or 4.10, and the reason they can be sold for much cheaper is there is way less R&D involved. Not sayin my conspiracy theory is true, it would just explain alot. So if this were true it would make the central 20 product just as reliable as 350evo's I would guess unless lesser materials were used.