While a more aggressive boost pin is often seen as more desirable, it is not the whole picture. For maximum power (or economy) the max fuel should be adjusted to be a similar air to fuel ratio across the range of rpms and boost pressures. To that end, Bosch specifically matches the boost pin profile to the spring rate of the pin spring. If a more aggressive pin (Rover) is used with a less aggressive spring (AAZ), then the result is that the fuel increases much faster than boost causing a significant increase in the fuel to air ratio. This is neither good for fuel economy or power as it results in either an excessively underfueled off-boost setting (lacking power) or an excessively over-fueled on boost setting with resultant overly high EGTs. If installing a more aggressive pin, for best results one should also install the matching spring and adjust the seat height, pin rest height and cone rotation to give an even fueling and then adjust the max fuel screw to the desired power/economy setting.Andrew
I wasn't trying to knock your offer, just putting out info so folks can make educated decisions. The rover pin would be an astounding improvement over the AAZ "joke" pin, it's just even better if the other parts are swapped over at the same time.