Is anybody using their original Tic Toc tack on their G3 swap? I have a Hotwire harness and Chris ran a primary coil wire inside for me and said to use a Dakota Digital SGI-8 adapter. I tried everything to get it to work but no luck. I emailed DD and got this response which basically says no from what I get.
Coil Over Plug (COP)
Some newer engines like the Hemi or Ford 5.0 use a single coil per cylinder.
If they do not have an ECM for a tach signal they will get the signal from the coils.
This requires a unique setup:
MSD GMR part 8918 will clip around a single coil positive wire.
Soft set the SGI-8 to 2 cylinders, set switches to 8 cylinder out.
The customer must have a tach selectable to 4 cylinders.
This is a simple ratio problem - 2 in 8 out (actual 1 in 4 out)
1 pulse per revolution, we can only set to a minimum of 2 cylinders
This is1/2 the input so we will double the out to 8 to make up for it
yet that only puts out a signal as a 4 cylinder,
so that is where the customer needs a tach that can be set to read as a 4 cylinder.
Link to MSD install guide
MSD says the 8918 has a 12V square wave 20% duty cycle.
For those who have only an 8 cylinder tach the Autometer 9117 tach adapter will be a better choice.
The Autometer 9117 can tap into multiple coils to give the SGI-8 a two or four cylinder input.
Link to install guide
MSD also makes the Dis-Tach Driver pn 8913 but they do not have instructions to make the cylinder count additive like the Autometer 9117.
This may work for the low voltage Buick Grand National tach signal.
MSD says the 8913 has a 12V square wave 20% duty cycle.
