Ray:
Just picked up a new, well new to me B4.2. In your tuning chart, which BTW is the best I've seen in RC!, you mention under high temperature conditions to use a 3hx1.4 optional piston. When I search Google (not that Google's perfect) for 3hx1.4 it only finds your tuning chart. What are the part numbers of these babies please?
Normally under really hot conditions you would just increase the viscosity by 2.5, can you elaborate on the type of improvement gained between the old way and using the optional piston?
Thanks