'66 289 FB edelbrock performer,holley 4160 500 cfm,pertronix ignitor and coil,stock distributor,headers,flowmaster,tremec5sp. Was running great.
Parked it to install TCP rack and pinion. Went for a test ride and ran rough as though it was low on fuel. Progressively worse , now won't idle, surges about 600 rpm at 2000 rpm and runs fairly smooth only at 3000 rpm. Had the ignitor checked by pertronix and was fine, checked fuel supply, took apart as much as I could of the carb and found no problem. I did not change anything in the engine recently and timing was spot on prior to this problem but now runs so bad impossible to check. Still seems like a fuel problem to me. What do you think ? Retroman

 

What do your spark plugs look like? I'd start with checking them if you haven't.

 

Sounds like a vacuum leak or firing order issue. Other than that look for maybe a fuel line pinched during the rack install.

 

Check for a vacuum leak, after that if it still does it(no leak found) then take the carb apart and blow carb cleaner through all the passages etc to clean it out. Sounds like it could possibly be a clogged idle circuit(among other things).

 

Many thanks. Will proceed with vacuum check and idle circuit carb check. Retroman