My experience in Retro racing is that the tapered pinions are more accurately machined than most of the straight pinions, and therefore give a better mesh. There may also be some benefit when running the large amount of hypoid offset that many of us do (around 1.3mm). Certainly I can get much smoother, quieter mesh with a tapered pinion.
What I haev found when using a 72DP pinion with a 64DP gear is also in inline racing with large hypoid offsets. I have used the aluminium Sonic drag gears (64DP) with straight cut Sonic 72DP pinions, and that also gives a nice smooth mesh. The reason I think is that the effective pitch of the gear as it meshes with the pinion in a hypoid setup is smaller than true 64DP. I think the guys running 1/32 F1 Eurosports do the same for the same reason.
I have not seen anyone running 80DP pinions on 72 DP gears in an anglewinder setup, but I would think that if there is a combination of a big angle and a fair amount of offset of the pinion below the gear, the same theory would apply.
What I haev found when using a 72DP pinion with a 64DP gear is also in inline racing with large hypoid offsets. I have used the aluminium Sonic drag gears (64DP) with straight cut Sonic 72DP pinions, and that also gives a nice smooth mesh. The reason I think is that the effective pitch of the gear as it meshes with the pinion in a hypoid setup is smaller than true 64DP. I think the guys running 1/32 F1 Eurosports do the same for the same reason.
I have not seen anyone running 80DP pinions on 72 DP gears in an anglewinder setup, but I would think that if there is a combination of a big angle and a fair amount of offset of the pinion below the gear, the same theory would apply.
