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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,

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Old 09-14-2009, 12:40 PM   #61 (permalink)
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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
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Old 09-14-2009, 04:11 PM   #62 (permalink)
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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?
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Old 09-14-2009, 04:15 PM   #63 (permalink)
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that's the price
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Old 09-14-2009, 04:33 PM   #64 (permalink)
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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.
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Old 09-14-2009, 04:34 PM   #65 (permalink)
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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???
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Old 09-14-2009, 05:16 PM   #66 (permalink)
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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.
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Old 09-14-2009, 05:27 PM   #67 (permalink)
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that's the price
What do you get to install them Russell?
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Old 09-14-2009, 06:20 PM   #68 (permalink)
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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!
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Old 09-15-2009, 11:52 AM   #69 (permalink)
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Quote:
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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

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Old 09-15-2009, 12:38 PM   #70 (permalink)
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Whoops, wrong z1
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Old 09-15-2009, 01:12 PM   #71 (permalink)
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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....
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Old 09-15-2009, 06:06 PM   #72 (permalink)
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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
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Old 09-21-2009, 08:28 PM   #73 (permalink)
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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!
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Old 09-24-2009, 12:32 PM   #74 (permalink)
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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.
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Old 09-24-2009, 01:11 PM   #75 (permalink)
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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.
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