The Definitive Differential Thread

[filip00]

I would recommend going with OS Giken. I track the car, take it for drift events and the LSD works incredibly well.

The maintenance boils down to changing the fluid every year or two, depending on mileage and usage. OS Giken plates aren't meant to be maintained.

Gearing is a better topic...depending on if you plan on boosting the car or keeping it stock, you might want to go with a shorter final drive.

[Spooler]

Originally Posted by filip00

I would recommend going with OS Giken. I track the car, take it for drift events and the LSD works incredibly well.

The maintenance boils down to changing the fluid every year or two, depending on mileage and usage. OS Giken plates aren't meant to be maintained.

Gearing is a better topic...depending on if you plan on boosting the car or keeping it stock, you might want to go with a shorter final drive.

For a NA track car to most people run 18in wheels on that would not be wise. For a boosted car with 18's, they go to 3.33's.

[filip00]

Originally Posted by Spooler

For a NA track car to most people run 18in wheels on that would not be wise. For a boosted car with 18's, they go to 3.33's.

Agreed. There are other variations though...I have a street/track car, with 19s, so shorter gearing is very nice. Boosted definitely requires longer gearing, especially on 18s, as you said...

[xavier]

Hi,

If I understand correctly.
With a 7AT VLSD 370z car.
If I want to install a 350Z MT VLSD (or 370Z MT with VLSD) pumpkin on a 370Z 7AT car (or 370Z MT car) , with Quaife (QDF13L).
I'll need two short flanges.
2 solutions...
1) (driver) flange 38220-1NC1B and (passenger) flange 38220-1NC1A, and it need to cut the 38220-1NC1A flange. The 38220-1NC1A flange loses a spline length.
2) Buy two 38220-1NC1B flanges (because it's short) to use on the passenger and driver sides (without to cut). This way, I have a longer spline length on the passenger side... identical to the driver's side longer spline length and with a gasket too.

Correct?
Image2.jpg

in the solution number 2, with two 38220-1NC1B flanges , passenger and driver sides:
more longer spline length = more power transmission, or, more strong.
i will use two 38220-1NC1B flange, not flange 38220-1NC1A with cut, does 38220-1NC1B flange will have same comportment than flange 38220-1NC1A cut ?

for information, the pumpkin of the 350z MT (3.538) is identical (external) fixing points on the 370z 7AT, identical height for the drive shaft and the transmission universal joints as on the 7AT (3.357) 370z, no misalignment (on 2 European cars, 350z MT and 370z 7AT) with the axes, checked at 0.5mm on the fixing points on the chassis, and on the rotating axes.

pictures (38220-1NC1B and flange 38220-1NC1A) come from Z1motorsports
https://www.z1motorsports.com/rear-d...ft-p-4622.html

38220JK01ADetailsHalf.jpg
38220JK01BDetailsHalf.jpg

38220-1NC1B = 38220-JK01B
38220-1NC1A = 38220-JK01A

Many thanks

[xavier]

Originally Posted by xavier

Hi,

If I understand correctly.
With a 7AT VLSD 370z car.
If I want to install a 350Z MT VLSD (or 370Z MT with VLSD) pumpkin on a 370Z 7AT car (or 370Z MT car) , with Quaife (QDF13L).
I'll need two short flanges.
2 solutions...
1) (driver) flange 38220-1NC1B and (passenger) flange 38220-1NC1A, and it need to cut the 38220-1NC1A flange. The 38220-1NC1A flange loses a spline length.
2) Buy two 38220-1NC1B flanges (because it's short) to use on the passenger and driver sides (without to cut). This way, I have a longer spline length on the passenger side... identical to the driver's side longer spline length and with a gasket too.

Correct?

Hi,

I got a verifiable and complete answer from a professional:
No.

You need a short flange for the original short side, and a long flange for the other side, and cut the long flange.

Why?
For the original short flange, the circular clip is on the flange and mounts on the original short side.
For the original long flange, there is a circular clip in the Quaife. the position of this clip corresponds to the location on the shortened long flange.

Indeed, the position of the clip on the short flange does not correspond to the notch on the long flange.
You must use a short flange for the original short flange side.
You must use a long flange, cut it, for the original long flange side.

example:
If two short flanges are used (and not a cut long flange), in a turn after a support that requires lengthening, the short flange (original long flange side) will slide into the Quaife. As they slide, the splines will decrease in length, and depending on the power/torque, the splines may break as the spline length decreases.

I asked if it's possible to modify the short flange to fit the clip (and to put in long flange side position). No.

the circular clip are not at the same position long or short flange.
http://www.the370z.com/attachment.ph...1&d=1754936991

Best regards
Xavier

[filip00]

You're not cutting any flanges, you'll just buy another shorter one. The flange has a circlip at the end and I'm not sure how you'd get a proper fit if you'd be cutting it yourself.

[filip00]

I mean, I may be in the wrong here....but many, if not most aftermarket LSDs for our cars will advise you to swap flanges to have two shorter ones, as that will accomodate the necessary space for the LSD. Having an aftermarket LSD made for the R200 housing, that actually requires you to hack the flange, seems to me kinda dodgy. I don't know. Maybe someone else can chime in and give their two cents.