Hey Guys,
I feel like a prize idiot. I purchased a MSD Street Fire HEI distributor for my 1971 RS 350 thinking that converting from points would be nice and easy. Well, for a rookie learning to wrench, it has proven otherwise. She doesn't even start..
Here are my really dumb questions all lined up for you...

1. There are 3 wires that were connected to the old coil. On the (+) side there was a Brown and a Tan (possibly) on the (-) there was a Red wire. On the new MSD, there is a spot for Batt and Tach, which goes where? Hopefully, this will help my car start.

2. What timing advance curve should I aim for?

3. What spark gap should I set for running a HEI?

 

1.) The wire that was on the + side of the coil is a resistance wire supplying 9~10 volts. The HEI distributor needs to be powered by a full 12 volt supply. Connect a new wire, with an inline fuse, to the keyed/switched ACC terminal on the fuse block, other end goes to the Batt terminal on the HEI. Verify operation with a test light or meter.
One of the two wires on the - side of coil went to the old distributor, all that goes bye-bye. The other wire goes to the tach, which connects to the Tach terminal on the HEI.
2.) Start out setting base timing at 10 degrees before tdc and see/listen to how the engine performs. If you get pinging (marbles in the cylinder) when under load, back the timing off a couple degrees and drive again.
3.) This is where you may get a handful of recommendations/opinions. Spark plug gap is based on engine build variables, there is no blanket gap setting. But as a rule of thumb setting, MSD recommends a .050"-.060" gap on engines having up to a 10.5:1 compression ratio, .040"-.050" gap with a 10.5:1-13:1 c.r., and .035"-.040" 13:1 c.r. and above. I set them at .045" with an HEI ignition.
4.) (not asked) Hopefully you installed the new distributor in the same rotor to plug wire on cap position as where the old one was removed. If not......to be continued!

 

Thank you Camaro 69!!!!!
Figured out the correct wiring and she fired right up! Who would've thunk that the small 12V wire would derail the complete distributor install. Adjusted my spark plug gap to .045 and now just to set the timing! Thanks again for the great advice, this is a great resource!

 

Great stuff guys. I'm doing the same thing (for the 3rd time - in a different car) and forgot whether the power wire had to be "full" power or through the "resistor" - which now I know again.
Hope to have wired today and ready to fire up once I figure out which oil filter adaptor I can use as is? I bought 2 different ones and both vendors say it can't be used that way. WTH??