my 235 in my 54 truck is backfiring alot, i know the rochester might be a t fault but wanted to cover all the other stuff first to eliminate them. i have new points and condensor in the dist. and just set it with the blade of the old points in a rush but what gap do you guys recommend? also i'd like to set the timing. its a completly stock 235 what should the timing be at? are there any markings on the damper for TDC?

i pulled my plugs last night and they are all really really black, #6 being the worse

would a HEI or high voltage coil help burn excess gas any?