ballist resistor

[71cudda]

recently rewired my engine,440 w/msd ignition,tach is bouncing around when i turn on accessories, not sure what to do with ballist resistor wires and believe this is the problem,any input would be appreciated   thanks

[Bullitt-]

Old syle tac is suffereing from the multi- spark of the MSD...They sell a device to solve this.

[Bullitt-]

one of these
http://store.summitracing.com/egnsearch.asp?N=700+400122+4294925143+4294839065+115+4294849427

[71cudda]

the tach and the msd were in there before i fried the harness , when i hook up the ballist wires, it does not happen but car will not start after i shut it down

[Bullitt-]

could you have wired the tac, signal to the + side of the coil?....SB - side

[Chryco Psycho]

the ballast reister wires are not used , the MSd powers the coil tach feed is off the MSD box not the coil

[71cudda]

should the wires be spliced together or just taped off,what do you think is causing the tach to jump, its fine with the car running and lights on but once you add anything else like heat or wipers it starts jumping  thanks

[Chryco Psycho]

just tape the wires off , not sure why the tach is jumping