Fine tuning 77 GMC truck
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Fine tuning 77 GMC truck
Have swb stepside 77 GMC Sierra truck 250-6cyl, 1BBL, auto trans which I drive daily. Put a new float in gas tank 3 y.ago. My gas register doesn't function correctly. Is this fixable even with such old gauge technology?
Additionally, had carb rebuilt by reputable rebuilder. I can't seem to get the max performance out of carb it once had. Engine diesels(run-on) after turning off ignition. Set fast and curb idle RPM according to Haynes manual but still seem to lack top end pep. At one time I could hang with the best on interstate; now I'm hesitant to get on. Ignition timing(set to GM spec). New plugs and wires,coil, dist. cap,etc; vac advance works fine. Have all 3 necessary basics-fuel, air, and spark. The engine has a new head, excellent compression, bottom end bored over 60 with hot cam.The truck is running but there is room for improvement. What have I done wrong or overlooked?
All advice and info are very much appreciated. Thank you for your time and help.
Steve
Additionally, had carb rebuilt by reputable rebuilder. I can't seem to get the max performance out of carb it once had. Engine diesels(run-on) after turning off ignition. Set fast and curb idle RPM according to Haynes manual but still seem to lack top end pep. At one time I could hang with the best on interstate; now I'm hesitant to get on. Ignition timing(set to GM spec). New plugs and wires,coil, dist. cap,etc; vac advance works fine. Have all 3 necessary basics-fuel, air, and spark. The engine has a new head, excellent compression, bottom end bored over 60 with hot cam.The truck is running but there is room for improvement. What have I done wrong or overlooked?
All advice and info are very much appreciated. Thank you for your time and help.
Steve