rochester 2bbl jetting

[Rapid Robert]

awhile back I took my circle track 360 9-1, 2bbl engine into the dyno. after fireup he could not run it as he said it was too lean. it has 76's in there now (OE I would imagine)& I ordered several sizes larger jets. how many sizes up should I go (to get in the ballpark)? I think I'd rather be too rich than too lean??? It wont be dynoed but I dont want to have problem from being too lean. I'm ready to fire it up in the car. thank you for your time. RR

 

[teringer]

76 is big the problem with that carb is the brass tubes that are made into the venturi wont let the fuel flow they must be enlarged ,I would drill the bottom of the tube larger about 3/16 ,the holly 500 cfm uses 68-72jets on a 355 chevy , when we switched over ,if you enlarge the area around the jet in the carb you can switch to holly jets they are a little wider then the roch. and every body has them ,I had the same problem I think it was in the 80/s but was running 13 to 1 comp.and I was drilling mine out to size.