So, getting conflicting info on the use of the MSD Blaster 2 coil in an HEI swap without using a ballast resistor. MSD's instructions online are limited to say the least. Makes it look like that unless you are using an MSD box that you need to use their .8 ohm ballast resistor on the coil. They give the install with one of their boxes and then list install with the resistor for points and stock distributor systems.
Now, reading the HEI post here, if I understand correctly, the GM HEI module actually is sort of doing the job of a ballast resistor by regulating the voltage to the coil at different rpms.
So, if that is the issue then when doing the conversion to HEI with the Blaster 2 then purchase of their .8 ohm resistor is not needed and all should be fine. Is that correct or have I got it mixed?
Just don't want to toast a coil and have an issue with the car quitting.
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Put a line here as this is related, but off on a different tangent a bit.
Just checked the voltage readings on the car to see what was happening. All measurements using a Micronta digital multimeter.
Battery voltage baseline 12.77
Start car, warm, tacho steady at 750.
Charge rate at battery showing 14.6 to 15.05 fluctuating.
at 3500 rpm charge rate steady +/- .01 at a rate of 15.32
Voltage measured at module B termainal.
idle - 13.7 to 14.6 fluctuating
3000 rpm - 13.1 to 13.9 fluctuating
Voltage measured at + terminal on Blaster 2 coil
idle - 13.7 to 14.6 fluctuating
2000 rpm - 9.xx (wrote this down as an after thought and don't have exact 9 volt number.)
3000 rpm - 8.7 not much fluctuation at all, pretty steady.
Car has had the amp gauge modification done. As a note, the voltage regulator is chrome. Probably makes my car 3 seconds faster in the quarter
, but wonder if it is some different value regulator? Had a blue one years ago that was a fixed 13.5 or something as I remember.Concerned about the fluctuation in reading also. May be an issue of the multimeter sensitivity perhaps. Oh, and alternator is a swapped on high amp (80 I believe) off of the '73 Dart 318 parts car I had.
Thoughts?
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Next section. Story of quality perhaps. Swapped on a Wells regulator I had spare. Was not a new one granted. Came off a '73 parts car I had at one time.
Module at idle 12.94 - 13.19
Coil at idle 13.08 - 13.22
Module at 2000 rpm 14.03 fairly steady
Coil measured the same.
Head scratching time. Now have a tacho bounce like a miss on a plug. Check wires, all are on good, look at connections, all look fine. Tacho shows a definite dead miss type bounce. Stop car, pull wells regulator and put chrome one that was on the car back on, tacho now reads rock steady.
