HEI problems

[Darknight]

Car still aint starting. getting a blue white spark at plugs, but no juice to fire it seems like. plenty of fuel. TDC every time i redo the dizzy. its a convert to HEI, its getting 12volts, how do i check the dizzy itself. bought it off of a member who said it was limited use, well the plunger and rotor where worn so i dont know if i can believe. how would i go back to my old points just to see if it starts. run a 12 volt to coil, ground coil and run that to dist? or run a wire from big ter on starter to r terminal, then r terminal to coil? beats me but a good HEI at store is 200, and i am running out of cash. it

[Eric]

If you're getting spark- even if it's weak- it should still try to fire up- it just won't run long or well. If you really suspect it's a weak spark- trying narrowing the plug gap from .045" to somewhere around .030" and see if anything changes.

More than likely it's something less exotic- like too much or too little fuel, or distributor is rotated 180* off- when you put #1 cylinder at TDC are you sure the cylinder on on the compression stroke and is the rotor almost pointing at the #1 plug wire terminal?

If you want to put you original points unit back in just to test- find that ballast resistor that was in-line with the power wire, reinstall it so that the coil gets 6V (not 12v this will burn things out) and leave everything else the way it is. You could even run a wire straight from the battery through the resistor before getting to distributor if it's only for temporary testing.

All that being said- usually if you're getting spark from an HEI setup- you're good- it's extremely (extremely) rare for an HEI to "under-power" on its own- more times than not the ignition module inside goes bad and you get NO spark. You mentioned somewhere else the HEI is being powered straight from the fuseblock. Try running a wire straight from battery to the BAT terminal on distributor- sometimes if there are other devices on the same line in the fuseblock they all get slightly less than 12V- and underpowering the HEI would cause a weak spark.