Dali Racing Acura NSX Catalog : Rotors '97+ 2-piece

Rotors '97+ 2-piece

Rotor Details:

Some product specific features are protected by patent application:

US Patent Application S/N 10/861,213
Filing date: 6/3/04

A brief description follows:

The cooling vanes are of a convergent nozzle design, which increases airflow and turbulence to improve cooling. (Fig 1)
The center-mount flanges for hat mounting on the rotor ring have several design benefits. (Fig 2)

They allow the ring to be used on either vehicle side simply by mounting the hat on either side of the ring.
The stress load transferred from the ring to the hat is balanced.
Air inlets to the vane openings in the ring are large and open to both inboard and outboard sides of the rotor.
Heat transfer from the disc surfaces to the hat is minimized by increasing the flange length and the airflow around the flanges.
Mounting to both friction surfaces as opposed to one provides better heat balance.

Other design features include:

Exclusive full floating design with 10.9 grade alloyed hardware. Hardware is DACRO coated and crimp locking. DACRO is highly corrosion resistant and provides a film for motion between the hat and rotor ring and the crimp design provides positive engagement for no rattling or torque loss at temperature.
Alloyed iron formula adds strength and thermal resistance and the heat treating further improves performance.

In case you didn't know, according to the UPS scale, the OEM Acura rotors weigh in at:

Front: 16.15 lbs
Rear: 14.15lbs.

Them racy ones:

Front: 12.18 lbs
Rear: 12.12 lbs

You save 10 lbs of unsprung weight (I read somewhere that is a good thing).

More on rotor design & hardware installation:

It is key to understand exactly how the crimp locking works if you are going to understand assembling the rotors.

The crimp nut slightly deforms the threads with serrations on the threads to mechanically lock the fastener at the pre described torque. You have probably seen fasteners that work on the same principle before - it works by whatever your tightening actually 'cuts in' a little to the other part and so its locked. But if you work it back and forth it'll loosen up and after a while not work anymore.

It works perfect for what we need - to hold a light torque number 'mechanically' - But when you use you tighten to a spec and then leave it. Rocking it to check torque etc. will ruin the locking holding power.

You also have to understand the rotor floating design. There is movement between the hat and rotor flange. That is why the hole in the rotor ring is an oblong slot - to allow for it. The nut is assembled lightly - just enough to hold the ring in place on the hat but not clamped hard so the ring can grow when it gets hot (the rotor flange also locates the ring on a 'ridge' in the hat).

A brief description follows:

Other design features include:

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