Nissan 370Z Forum  

VHR + FD Gear Ratio upgrades - 3.9 and 4.08

It has nothing to do with the SRM or the transmission in any way The comparison vs stock was posted - add 11% to your current rpm at any speed,

Go Back   Nissan 370Z Forum > Nissan 370Z Tech Area > Engine & Drivetrain


Like Tree10Likes

Reply
 
LinkBack Thread Tools Display Modes
Old 09-14-2009, 01:40 PM   #61 (permalink)
Base Member
 
Join Date: Aug 2009
Location: St. James, NY
Posts: 237
Drives: 350Z
Rep Power: 16
Z1Performance is on a distinguished road
Default

It has nothing to do with the SRM or the transmission in any way

The comparison vs stock was posted - add 11% to your current rpm at any speed, and that is where it will be with the new gears installed

The benefit is quicker acceleration in every gear
Z1Performance is offline   Reply With Quote
Old 09-14-2009, 05:11 PM   #62 (permalink)
Base Member
 
Join Date: Aug 2009
Location: Cerritos, CA
Posts: 39
Drives: 08.5 mazdaspeed 3
Rep Power: 16
steven88 is on a distinguished road
Default

Quote:
Originally Posted by Z1Performance View Post
It has nothing to do with the SRM or the transmission in any way

The comparison vs stock was posted - add 11% to your current rpm at any speed, and that is where it will be with the new gears installed

The benefit is quicker acceleration in every gear
Z-1 Performance Automotive Services Inc. - 4.08 Final Drive for 350Z/G35

any specials going down in the next month or so?

has it been confirmed that the 370z uses the same parts as 350z/g35?
steven88 is offline   Reply With Quote
Old 09-14-2009, 05:15 PM   #63 (permalink)
Base Member
 
Join Date: Aug 2009
Location: St. James, NY
Posts: 237
Drives: 350Z
Rep Power: 16
Z1Performance is on a distinguished road
Default

that's the price
Z1Performance is offline   Reply With Quote
Old 09-14-2009, 05:33 PM   #64 (permalink)
Enthusiast Member
 
Join Date: Feb 2009
Location: Double Oak Tx
Posts: 255
Drives: 370Z, 96CE hotrod
Rep Power: 16
Denny McLain is on a distinguished road
Default

Quote:
Originally Posted by Z1Performance View Post
that's the price
Looks like a multiple-choice answer to me. Exactly what do you need for a 370Z?

Also, with you all the way that a 3.90 gear would be a waste of time and money. On a F-body I went from a 3.42 to a 3.73 and it did basically nothing.

My rev limit is set @ 8000 rpm and with 4.08 gears top speed in each gear is:

1 41mph
2 67mph
3 95mph
4 122mph
5 155mph
6 195mph

Something just a tad steeper might be even better.
Denny McLain is offline   Reply With Quote
Old 09-14-2009, 05:34 PM   #65 (permalink)
A True Z Fanatic
 
Join Date: Apr 2009
Location: Sacramento, CA
Posts: 2,188
Drives: 370z MB 6mt
Rep Power: 914
shabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond repute
Default

So correct me if I am wrong - but the SRM basically functions using a look up table... IE: if your speed is X in gear A... then when you shift to gear A-1 rev to RPM R... so.... if you were to now change your gears to higher FD... you will be at a higher RPM for lower speeds - so wouldnt this cause the SRM to rev to a lower RPM making for some interesting shifts???
shabarivas is offline   Reply With Quote
Old 09-14-2009, 06:16 PM   #66 (permalink)
Enthusiast Member
 
Join Date: Feb 2009
Location: Double Oak Tx
Posts: 255
Drives: 370Z, 96CE hotrod
Rep Power: 16
Denny McLain is on a distinguished road
Default

Quote:
Originally Posted by Denny McLain View Post
Looks like a multiple-choice answer to me. Exactly what do you need for a 370Z?
Answered my own question. Amazing what happens when you read something.

What about gear noise? Typically higher gears are noisier.
Denny McLain is offline   Reply With Quote
Old 09-14-2009, 06:27 PM   #67 (permalink)
The370Z.com Sponsor
 
Mike's Avatar
 
Join Date: Jun 2009
Location: Loganville, GA
Posts: 5,944
Drives: 370z
Rep Power: 2186
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Quote:
Originally Posted by Z1Performance View Post
that's the price
What do you get to install them Russell?
__________________
NISSAN: 75 280Z / 86 300ZX GLL /87 Sentra SE / 03 350Z / 23 Z
Porsche: 93 968 / 23 Macan GTS / 93 968
Mike is offline   Reply With Quote
Old 09-14-2009, 07:20 PM   #68 (permalink)
Enthusiast Member
 
Join Date: Feb 2009
Location: Double Oak Tx
Posts: 255
Drives: 370Z, 96CE hotrod
Rep Power: 16
Denny McLain is on a distinguished road
Default

Sold.... Credit card order sent in.

Was just about to order a set of sway bars and saw the thread. I'll get the sway bars a little later......gears make ya go faster.

Nice to see some real mods comming down the line. Nice answers to the questions!
Denny McLain is offline   Reply With Quote
Old 09-15-2009, 12:52 PM   #69 (permalink)
Base Member
 
Join Date: Aug 2009
Location: St. James, NY
Posts: 237
Drives: 350Z
Rep Power: 16
Z1Performance is on a distinguished road
Default

Quote:
Originally Posted by Mike View Post
What do you get to install them Russell?
I'm not Russell, nor is there anyone here by that name, sorry - I am Adam, our other employee on this board is Kwame

I have not spent time looking up the 370Z bearings just yet, but we'll get those listed in the next week or so once I get them organized and pricing sorted.

Noise wise, nothing to worry about at all - it's all in the install. Get the lash set correctly, and you'll be good to go

Last edited by Z1Performance; 09-15-2009 at 12:54 PM.
Z1Performance is offline   Reply With Quote
Old 09-15-2009, 01:38 PM   #70 (permalink)
The370Z.com Sponsor
 
Mike's Avatar
 
Join Date: Jun 2009
Location: Loganville, GA
Posts: 5,944
Drives: 370z
Rep Power: 2186
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Whoops, wrong z1
__________________
NISSAN: 75 280Z / 86 300ZX GLL /87 Sentra SE / 03 350Z / 23 Z
Porsche: 93 968 / 23 Macan GTS / 93 968
Mike is offline   Reply With Quote
Old 09-15-2009, 02:12 PM   #71 (permalink)
A True Z Fanatic
 
Join Date: Apr 2009
Location: Sacramento, CA
Posts: 2,188
Drives: 370z MB 6mt
Rep Power: 914
shabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond reputeshabarivas has a reputation beyond repute
Default

Quote:
Originally Posted by shabarivas View Post
So correct me if I am wrong - but the SRM basically functions using a look up table... IE: if your speed is X in gear A... then when you shift to gear A-1 rev to RPM R... so.... if you were to now change your gears to higher FD... you will be at a higher RPM for lower speeds - so wouldnt this cause the SRM to rev to a lower RPM making for some interesting shifts???
Umm no answer? Or do you just not know about this? I would imagine this would keep a LOT of people from buying gears for this car if the issue exists....
shabarivas is offline   Reply With Quote
Old 09-15-2009, 07:06 PM   #72 (permalink)
Base Member
 
Join Date: Aug 2009
Location: St. James, NY
Posts: 237
Drives: 350Z
Rep Power: 16
Z1Performance is on a distinguished road
Default

SRM is not intuitive - ie it does not know what gear you are going to select

SRM works off the speed of the wheel, via the ABS sensors, the shift lever position and clutch pedal position. It is, for all intents and purposes, automated heel-toe. It also can be turned off
Z1Performance is offline   Reply With Quote
Old 09-21-2009, 09:28 PM   #73 (permalink)
Base Member
 
Join Date: Apr 2009
Location: Chile
Posts: 20
Drives: 370Z 7AT Touring
Rep Power: 16
javol is on a distinguished road
Default

Quote:
Originally Posted by Z eliminator View Post
I changed the diif on my 7 AT to a 4.08 gear set up.
What do you change exactly?

Do you install an aftermarket 350Z ring-pinion couple or what?

Thanks!
javol is offline   Reply With Quote
Old 09-24-2009, 01:32 PM   #74 (permalink)
A True Z Fanatic
 
wstar's Avatar
 
Join Date: Mar 2009
Location: Houston, TX
Posts: 4,024
Drives: too slow
Rep Power: 3594
wstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond reputewstar has a reputation beyond repute
Default

Quote:
Originally Posted by shabarivas View Post
Umm no answer? Or do you just not know about this? I would imagine this would keep a LOT of people from buying gears for this car if the issue exists....
My assumption (but I don't know for sure) is that SRM works off of gear and RPM alone, as that makes the most sense and is simplest to implement anyways. Assuming that's the case, changin rear diff ratios and/or tire/wheel sizes won't screw up SRM. If a rear diff ratio does screw up SRM, then so would any aggressive change in tire diameter, and that would be just plain silly on Nissan's part and people would've noticed it by now.
__________________
7AT Track Car!
Journal thread / Car setup details
wstar is offline   Reply With Quote
Old 09-24-2009, 02:11 PM   #75 (permalink)
The370Z.com Sponsor
 
Mike's Avatar
 
Join Date: Jun 2009
Location: Loganville, GA
Posts: 5,944
Drives: 370z
Rep Power: 2186
Mike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond reputeMike has a reputation beyond repute
Default

Quote:
Originally Posted by wstar View Post
My assumption (but I don't know for sure) is that SRM works off of gear and RPM alone, as that makes the most sense and is simplest to implement anyways. Assuming that's the case, changin rear diff ratios and/or tire/wheel sizes won't screw up SRM. If a rear diff ratio does screw up SRM, then so would any aggressive change in tire diameter, and that would be just plain silly on Nissan's part and people would've noticed it by now.
and since I'm running track tires that are 1" shorter than stock and it still works fine, I believe you are right.
__________________
NISSAN: 75 280Z / 86 300ZX GLL /87 Sentra SE / 03 350Z / 23 Z
Porsche: 93 968 / 23 Macan GTS / 93 968
Mike is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Problem after some Audio Upgrades 209Z Audio & Video 1 06-13-2009 02:16 PM
6th Gear Syncros going after 5K. Scribe Engine & Drivetrain 50 05-22-2009 03:54 PM
first to second gear.. DJcuetip Nissan 370Z General Discussions 3 02-06-2009 11:42 PM
Top Gear? 370z2 Nissan 370Z General Discussions 1 02-04-2009 12:43 AM
Close ratio gears? tvfreakazoid Engine & Drivetrain 24 01-30-2009 04:44 PM


All times are GMT -5. The time now is 12:41 AM.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 PL2