Entaille

iTrader: (16)

I dug around and found a g35 5at owner with 4.083 gears and he was pretty happy with them. said that they were fine in commuting scenarios and when he wanted to get on it it was absolutely awesome.

also had the transgo kit. nothing concrete, just happy that I found someone with it that was happy with the results.

scotts300

iTrader: (46)

A local shop owner put the 4.083s in his 6MT 350Z and loves it. It pulls hard, see some vid here (after the 1:50 mark):

http://www.youtube.com/watch?v=jc27teFar8k

myroncuz

anyone got extra shims lying around? ill pay for them. want extra for when i do my install. please let me know. thanks

jmccarty

Z1, Kwame or any of you that may know, I live in Singapore where the X-Trail (and parts) is common but we do not have the Frontier. The X-Trail is listed as a 4.087 final drive in the AT model. Any reason you can think of why this may not work for my M/T? Btw, I am changing my Nismo 1.5 LSD to a Quaife as I write this and difs and final drives are not my best area of knowledge.

I have read a lot of threads on the 3.9 & 4.08 and see that fitting the 4.08 to an A/T adds more parts and effort, what about the other way around? Using the final drive from an A/T for a M/T?

The M/T X-Trail is listed as 4.428 so I don't even want to go there.

Any advice appreciated.

Z1 Performance

iTrader: (564)

it won't work, auto's use totally different ring and pinions (and diffs) vs MT cars

if you need one, let us know..we have the 4.08 in stock and can have it to your doorstep quickly (lots of customers in Singapore)

jmccarty

Thanks Adam, I may be ordering one from you soon if I can't find it locally.

jmccarty

Adam - Not a chance of getting a 4.08 drive here and I will be ordering from your website as soon as I finish this message.

Btw - The Quaife LSD is magic!

jmccarty

Adam - Just sent you an email order through your website, email or PM me if you need any other info and thanks in advance.

Z1 Performance

iTrader: (564)

got it Jim, thanks

any questions, I'll either email you back or pm you here

jmccarty

So theoretically, if I shift (at a rev limit) at 8,600rpms with 285/35/19 tires and the 4.083 final drive I could still reach 212mph in 6th?

Z1 Performance

iTrader: (564)

sounds about right yes

drag limited is really what determines things at those speeds though

Russ

iTrader: (3)

Yup, I agree. Theoretically (assuming ideal numbers) you'd hit 212

Last fall in an issue of Modified they had a graph for their gear swap in an NSX
http://www.modified.com/tech/modp-09...all/index.html

I liked the graph they showed on page 4 of that article so I decided to make one for the 350Z 6MT:


I've attached a graph and my handy dandy spreadsheet
Well at least, I think it's handy dandy anyway
Just go to the "Calculation" tab and edit the "Max RPM cell" (B15) and the
"Rear Tire Size" cell (B17) in width/aspect_ratioRrim_diameter format
then go to the "MPH vs RPM plot" tab to see your results

The attached is for your numbers 285/35R19 tire with max rpm of 8600
The blue lines are stock final drive (3.538), green are 3.917 and red are 4.083
1st gear are the lines ending in the lower right and 6th gear are the lines ending in the upper right

scotts300

iTrader: (46)

Thanks! I've already adapted your handy dandy sheet for my current 285/30/18 tires and am comparing it to my proposed 295/30/18 and 305/30/18 tires as I consider the 4.083 gears over my current 3.538s!

Nexx

iTrader: (41)

lol someone posted this in the 350z vs 370z drag race thread just to point out how a bolt on DE could keep up with a 370z at the track, no mention about the gears which makes a HUGE difference.

scotts300

iTrader: (46)

Now that's funny, because I am the one who posted that video! I do have the stock 3.5 gearing and was running 285/30/18 tires versus the 370s 4.08 gears and 285/35/20 tires.

Here is the entire vid of the 350/370 chase. On multiple occasions you get to see the two cars differ over 15 minutes of track driving. The 370Z comes in at the 2min mark.
http://www.youtube.com/watch?v=sFuOcX4MQ_U

jmccarty

Russ - That's a handy graph.

I don't think I'll attempt to reach that theoretical top end. But interesting!

jmccarty

Adam - Shipped yet?

rdrfronty

Hey guys I hope you don't mind me posting here. It's pretty hard to find good information like this thread has, so I was wondering if i could get some opinions. As my signature says I have a Frontier with VQ40 and 6spd. I have stock 3.54 gears and crappy electronic controlled(via the brakes) limited slip. I also have ET streets that I use at the track. Et's are 28" tall. Street tires are 30.5" tall. My gears are 1st-4.368, 2nd-2.518, 3rd-1.743, 4th-1.283, 5th-1.00, 6th-.769. My stock redline was 6250rpms, since my recent cam install, Uprev raised my limit to 6800rpms. My peak power is about 6300rpms. Also, racing weight with driver is appx 4250lbs.
So my issue is trying to get a good launch. Right now I either have the choice of a mild launch with creates a mild bog, which I'm assuming is due to my cams moving my rpm band up some . If I get a little aggressive-2500rpms or up, I just boil my tires(the ET streets). I'm assuming the excessive spinning is because I'm getting closer to my power band and the fact I dont have true limited slip.
So my planned solution is to install Truetrac limited slip(mechanical) and 4.10 gears. I'm hoping that Truetrac will give me a decent chance of hooking up, plus allow me to get more aggressive with the launches-maybe 3000K or so. If the 4.10's don't trump the Truetrac too much with more lose of traction, I'm hoping they will move my (appx 800lb more than you guys)down the track easier plus more important get me into my power band faster.
My 14.27 in the 1/4 was before my cam install. I didn't gain alot from the cams--appx 12whp & 10ftlbs of torque, mostly 3000-6500rpms gains, but I can feel it for certain when playing around town. I'm thinking my launch is my issue keeping my times from breaking into the high 13's. So will gears help more on a heavier vehicle like mine? Or am I making a mistake?
I know I don't have a Z, but my drivetrain is pretty similar, and unfortunately the Frontier forums are joke to get good answers about issues like this. Any opinions or advice would be greatly appreciated.

scotts300

iTrader: (46)

You boil ET streets? What pressure? I launch my 300ZX TT (~650rwhp) at 7k with them and they sure don't "boil".

rdrfronty

About 22psi since my racing weight is about 4250lb. But remember thats basically a "1 tire" boil. And yes I warm them up first. My SE Frontier limited slip is just useless at the track. Here is a recent attempt--launched at about 2500 and slipped it even a little.
http://www.youtube.com/watch?v=KaFtLvFBh3c