JonnyD757

MSD Blaster

JonnyD757

Located in Souderton, PA. About 45 minutes NW of Philly

SB

iTrader: (1)

Blaster II or Blaster HVC canister coils can be used with the Tbolt IV as they have the proper .7ohm primary resistance Tbolt IV requires.

MSD typically had more issues and sooner than the Merc ignition parts, but that shouldn’t stop you from using the coil for diagnostic reasons.

btw: reving engine on hose requires squat fir fuel nor spark, so will not help disgnose issues that happen under load when tons of fuel and spark are needed.

AllDodge

iTrader: (1)

Would the distributor pickup happen to be a 2 wire and not 3 ?

SB

iTrader: (1)

I’m not nearby but slight side track. Several times a year (early thru mid late nineties) we used to base out of Pottstown (right near you of course) to street race fri-sat nights and then finish in car dealer/junk yard area of Philly then point north and head home.

JonnyD757

Been there done that. Fun times.

F-2 Speedy

iTrader: (6)

Thats a problem with a Merc distributor, I had one that was over heating the timing module to the point of failure, put the stock mercury coil on problem resolved...the mecury coil has some resistors in it and the msd ( may soon die ) does not

JonnyD757

It is a 2 wire. Meaning two wires coming out of the distributor

SB

iTrader: (1)

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Only a problem when the MSD blaster II isn’t up to spec. Msd sucks, we know. Lots of problems.

However, when it’s built correctly it is fine with the Tbolt IV module. Tbolt coil spec is .6-.7 ohm. Blaster II oil and epoxy cannisters .7ohm.

Resistance usn’t added internally or externally like the old days of 1.5ohm v8 coils and 3.0ohm 4 cylinder coils.

It’s simply resistance of the primary windings themselves.
The modules control the dwell of the spark per rpm so nothing ‘burns up’ at slower speed (lower dwell) and provide more dwell at higher speed along with a large current limiter setting to provide better spark at higher rpm.

The module is made for s certain spec coil, and that, again, is made for .7 ohm primary resistance coil. A coil with lower value will burn out the module and a coil with more resistance will provide less spark energy , again, because module made for that certain value coil.

AllDodge

iTrader: (1)

Merc found that the module can loose its ground (causing it to miss), so they changed them to 3 wire to run a ground to another location on the block. No guarantee but it was an issue