(edited because I wasn't paying attention) :spank: ou: Jamie, Larry below is right - with HEI your tach will work. :TU: BUT IF YOU HAVE AN MSD BOX,... Your tach won't work with the factory wiring, because the MSD box fires the coil multiple times and the tach would be reading insanely high - if it didn't burn up from the higher voltage the MSD sends to the coil. Factory tachs count the number of times the 12volt current through the coil is interrupted, and the MSD sends several hundred volts into the coil (using it like a transformer) which would melt your tach. On one end of your MSD box is a tach connector, a single blade connector. That's where you hook up the tach signal feed wire. It may not work, something to do with "square wave signals" or some electrical whatnot, and if that's the case, you need a MSD tach adapter. Your MSD box's instructions cover this, there are two types of adapters, and both are usually available on ebay used for about $25, or Summit wants $50 or so for a new one.
Yeah thats me with the MSD box. its ok though, it will save me some time wondering why my car is idling at 8,000 rpm
also were thinking about just buying the new MSD distributor, yes its more expensive, but i guess he likes new?
