[petek]

Jake ... on down shifts the engine won't fire, but it WILL overspin (driven by the rear wheels through the gearbox).

Ikestaa ... if I remember correctly the thing that sets the max rpm is a resistor so it shouldn't matter which way the thing is inserted. However, I have a Holley box and not the MSD box. Then again, if it mattered which way the "chip" went in and the engineer didn't design it to have a polarized plug / socket, then the engineer should be made to drive a Yugo!