PurpleBeeper
Well-Known Member
I've got a '70 Roadrunner 4-spd car with nitrous running a Direct Connection electronic ignition ('72-'73 style) with disconnected vacuum advance and an old MSD 6A ignition box. I have no ballast resistor and I have both the blue (run) & brown (start) ignition wires running to the red wire of the MSD 6A box.
I got a good deal on a MSD Digital Multi-Retarder, MSD Soft Touch Rev Control & MSD 2-step module and I need some help wiring them in. I plan to run 1/4 mile with this car, but I've never run a 4spd at the track. Attached is what I have so far as a wiring diagram.
My goals are:
1. Have a rev limit of about 6500rpm in case I miss a shift.
2. Retard the timing 2-5 degrees when nitrous is activated (depending on shot).
3. Retard the timing 2 degrees in 4th gear & be able to switch this function on & off.
4. Retard the timing 5 degrees when I'm starting the engine.
5. Set a rev limit of 2500rpm (???) connected to the line lock so I can focus on the clutch/gas/light when launching the car.
My questions are:
1. Does my wiring diagram look correct?
2. On the MSD Digital Multi-Retard "Mag Comp" circuit, do I set it to "6 MSD/Ford"? I think my other choices are "8 GM" and "0 MSD Crank Trigger".
3. How do I set up a 4th gear timing retard activation switch? Anyone have a picture of their setup? I'm "guessing" some type of nitrous-style momentary on WOT switch or something on the shifter???
4. Is my idea about a line lock realistic? I've never set a car up like this before. How do I stage the car? I'm thinking about using a momentary on button on the shifter, stage the car & light both small yellow lights, hit the brake, push the line lock button, move my right foot to the gas & rev it up until I hear the motor cutting out (2500 rpm???) and hit the gas/let out clutch/remove finger from line lock button to launch. Does that sound right?
I got a good deal on a MSD Digital Multi-Retarder, MSD Soft Touch Rev Control & MSD 2-step module and I need some help wiring them in. I plan to run 1/4 mile with this car, but I've never run a 4spd at the track. Attached is what I have so far as a wiring diagram.
My goals are:
1. Have a rev limit of about 6500rpm in case I miss a shift.
2. Retard the timing 2-5 degrees when nitrous is activated (depending on shot).
3. Retard the timing 2 degrees in 4th gear & be able to switch this function on & off.
4. Retard the timing 5 degrees when I'm starting the engine.
5. Set a rev limit of 2500rpm (???) connected to the line lock so I can focus on the clutch/gas/light when launching the car.
My questions are:
1. Does my wiring diagram look correct?
2. On the MSD Digital Multi-Retard "Mag Comp" circuit, do I set it to "6 MSD/Ford"? I think my other choices are "8 GM" and "0 MSD Crank Trigger".
3. How do I set up a 4th gear timing retard activation switch? Anyone have a picture of their setup? I'm "guessing" some type of nitrous-style momentary on WOT switch or something on the shifter???
4. Is my idea about a line lock realistic? I've never set a car up like this before. How do I stage the car? I'm thinking about using a momentary on button on the shifter, stage the car & light both small yellow lights, hit the brake, push the line lock button, move my right foot to the gas & rev it up until I hear the motor cutting out (2500 rpm???) and hit the gas/let out clutch/remove finger from line lock button to launch. Does that sound right?
