Swapping pinion and crown for GTR diff

[Yonz]

Hi all,

 

I've got a 350Z 6 speed manual in my R33, so I'm using an S15 crown and pinion (3.692) to bring all the gears back close to standard.

This pic might explain that better, it's my current setup Vs a standard R33

 

The diff will be taking some abuse once it's tuned and hitting the track, so I've lined up a 32GTR rear end to swap out.
I obviously want to keep that 3.692 ratio in the diff.

Will the 3.692 crown and pinion work in the 32GTR housing?

 

Cheers

[GTSBoy]

When you say "got a GTR rear end to swap out", are you saying that you've got the whole rear end?  Because you will need to keep in mind that there are a number of differences in the various attachments.

GTR diffs have 6 bolt stub axles and drive shafts, so you need those and the GTR hubs.  GTR diffs use a CV joint connection from the tailshaft to the pinion, so you need to either use the back half of a GTR shaft or change the input flange on the diff.

There are some geometry/width/arm changes between early (ie 32) and later (ie 33) rear suspensions.

In the face of all that, the question of whether the CW&P will install onto the GTR pumpkin is actually much less of a problem.  In general, yes they will.  Almost all of those R200 diffs are pretty much interchangeable in that regard. For example, I have an R34 4.11 CW&P installed onto an S15 helical centre in an R32 housing.  But you also need to be aware that there are 2 bolt sizes for attaching the CW to the diff centre, and that sometimes catches people out.  Shouldn't be a problem in your case.

All in all, it would probably be better if you obtained a 1.5 or 2 way mechanical aftermarket centre to put into your original R33 housing, keeping your 5 bolt shafts and so on.  The diffs themselves are all about the same physical strength, so you're not buying much extra strength with a GTR diff, and the 6 bolt driveshafts are only a little bit tougher too.

[Yonz]

By GTR rear end I mean the diff, shafts and hubs.

I'm mainly wanting to swap to the GTR setup for the 6x1 shafts, as I have 3x2 at the moment. (Bought the 33 ages ago with no drivetrain, so the standard diff is long gone)
I was intending on changing the input flange on the diff, as I already have a tailshaft made to suit the 350Z box.

Thanks for the insight on the crownwheels, I'll sus that out before I jump into anything

[jhjones]

Does the s15 diff have a speed sensor on the pinion? if so you need to put the gtr center an stub axles into the s15 diff

[GTSBoy]

That's actually a valid point!  Whilst the CW will usually bolt onto the centre just fine, I keep forgetting about those horrible diffs with speed sensors on the snout. The pinion from one of those may no fit into housing that doesn't expect it.  Best case, it goes in just fine.  Worst case, it's too long (because some of the single ABS sensor diffs have as slightly longer housing!) you might need some machine shop work.

[Yonz]

Nah no speed sensor, not that I can recall anyway.

Good to know though, thanks fellas