The R45 plugs are the standard replacement plug now. I've tried getting 43's, no go, also 44-5 commercial's because they are called out in the manual but they aren't made any more either. R45's are avalable everywhere from the vendors, farm supply and most FLAPS and run just fine in these engines.
Unless you're running something other than the Rochester 'B' or the throttle setting higher than the 450-500 rpm there is no need to disable the vacuum to the distributor when timing the ignition, the vacuum port is above the throttle plate.
Denny Graham
Sandwich, IL
Last edited by Denny Graham; 07/12/2011 1:07 AM.
