You don't need a Hyperspark distributor for timing control if you already have a MSD distributor. You can lock out the advance mechanism on the MSD and use a adjustable rotor to phase it properly. Also need to pay attention to good wiring practices with magnetic timing control as it is more prone to EMI.
I tried that when the Sniper first came out and it didn't work very well. It turns out that the MSD distributor isn't a very good match for the Sniper. The MSD produces a sine wave signal but the Sniper wants a square wave signal which is why Holley developed the Hyperspark. The Hyperspark uses a Hall effect sensor to produce a square wave digital signal that works well with the Sniper. The Holley forum is full of people who have had trouble getting their MSD distributors to work with the Sniper. The common advice now is for people to sell their MSD distributors and use the money to buy a Hyperspark.
Actually it works okay with a magnetic MSD distributor. Magnetic to Holley means sine wave. When I remote tune I sometimes have to be a remote mechanic as well, and what I run into with people that want to use their MSD dizzy is that the default Holley values for a magnetic pickup are wrong. The software defaults to a minimum signal voltage of zero volts. However, the instructions DO say that you should start at .35V. After I change that, my experiences have been very good. Then we have the rotor phasing issue that is mentioned above. That also must be done because the distributor must output at 50 - 60 degrees BTDC yet the rotor should be phased to its terminal at about 25 degrees BTDC. The most common reason that MSD distributors don't work well is that people didn't know where to find the instructions. I do one more thing not mentioned in the instructions - use shielded wire with the shield grounded at the Holley end.
