We now have drive collars for the Nissan RB cranks. These collars when installed correctly will provide a greater contact area over the standard flats on the crank when driving the oil pump gears, providing less wear and therefore the likelihood of the gear cracking reduces dramatically.
Bores are machined to Ø34.93 ±0.02.
Note: Crank collars require specialized machinery to install. Your existing crankshaft will need to be ground to size to be able to fit this collar.