New TURBO NC for XP Class...Our New "NC-EXTREME" PROJECT!

[Brian]

The Rear is In Gear...big THANKS to Ben at PuddyMod, who had AMAZING response time. Ben explains the setup thus:

Hi Brian,

I built you a PM Stage 2 setup with micro polished 3.73 gears. I also installed the OSGiken LSD and set the pressure springs according to what I believe will work best for your setup and needs.

The rear is rebuilt from the housing in starting with every part being cryogenically thermo cycled, then new pinion bearings and seals are used to assemble. There is a one piece PuddyMod solid steel sleeve used instead of an OEM crush collar. The solid sleeve is made of 10/20 mandrel steel, it is seamless and will not compress under heavy stress like the OEM can. Solid sleeves are used in high performance racing rear ends because they work, we just take it to the next level. The PM sleeve is a custom machined part to fit this rear, it is not shimmed it is a precision machined one piece steel sleeve. The stock hardware is replaced with cryo treated hardware. Backlash is set giving a tighter gear to gear fit.
Fully balanced assembly of the rear using precision accuracy to better than factory tolerances.

Here are your build pics and build information/specs.



this pic shows the assembly, note the PuddyMod solid steel sleeve on pinion.

[Brian]

More from Ben at PuddyMod

This pic shows the balance after balancing the carrier assembly, it is just over a half thousands true round! Note the micro polish on the ring gear.

[Brian]

This pic shows the PuddyMod solid steel sleeve being set, note the pinion gear is also micro polished.

[Brian]

This pic shows the preload on the pinion after the PuddyMod solid steel sleeve
Is set, it is at 12 inch pounds.

[Brian]

This pic shows the backlash at 2.8 to 3.1 thousands, note the perfect gear to gear pattern.

[Brian]

This pic shows the finished build, note the information on the OSGiken LSD





THE REAR IS SHIPPED DRY WITH OIL INSIDE PLEASE ADD OIL

BEFORE USE

Break in,

Use 10 oz of Amsoil SAE 250 in the rear along with Amsoil synthetic severe Gear 75/110 gear oil every 3K miles.

This mix will quiet the LSD pretty good, allow smooth operation, and provide added shock protection. Be sure not to over fill the rear, fill the rear until the oil starts to come back out of the fill hole. Replace the fill bolt once the oil slows to a light trickle, drip.

More Break in:

Drive the car like a civilized human for 300 miles, after 300 miles the rear is fully broke in and “normal” driving can begin.

I know you guys don't have time for a proper break in but, Try to put a few warm up laps on the rear to get it up to operating temp. and also allow for the bearings to take a seat.


Thanks

Ben

[George]

Very nice. I can't wait to hear what you think when you drive it.

[iniazy]

What is the standard diff ratio on the NC Miata? Is it 4.56:1?

[Brian]

Depends on where you are.... Here in the USA 4.1.

[iniazy]

Depends on where you are.... Here in the USA 4.1.

Does it vary elsewhere? I have a European spec Miata NC.

[George]

Depends on where you are.... Here in the USA 4.1.

Does it vary elsewhere? I have a European spec Miata NC.

In Europe it used to be 3.73 on the manual transmission cars, or maybe it was just the 6-speed. A few guys were trying to source US spec R&Ps because they wanted the 4.1.

[Nate Horne]

Any update on how the NC Extreme project is going?

[Brian]

A 'reflection' of how busy we have been this past year with the new shop opening, this poor project got pushed onto the back burner. We were just so consumed with growing into the new space that this project didn't get any love. But from this ghostly image in the alignment rack mirror you can see it is finally coming together. Hope to get it off to the dyno tomorrow, and if that goes well, then some Chuckwalla Raceway testing this weekend.