on a whim today i readjusted the timing because of something that i read by geezer101 wrote the other day
I have a tendency to not worry about a timing light other than using it as a diagnostic tool.
so on that theory i got out this morning and redid the timing first one way took it out ran it same thing blow back threw the carb so i come back to the house and went the other way with the timing and low and behold the blow back stopped i tested on a steep hill @ 70-75 mph one that i had run the other day that had issues @ 60-65 mph but this time it ran right up the hill WITHOUT any problems as far as blow back is concerned i still have a little bit of power lose but i think i can fix that by adjust and tweaking the cab and the timing together. but as for putting a timing light on it and setting it to factory specs it throws it way off *as in performance* and cause's a lot of issues.
learn something new everyday thanks gezzer101 for the advise given to mikclson .