Originally Posted by Silver00V6
read above my vac with the advance plugged up is 30 degrees. Both primay and secondary butterlfies are closed. the only idle screw that will kill the motor when going lean is the passenger side the driver side will do nothing but will go rich if you turn it out. I have tried the wire thing in the idle feed restrictors and it is still rich smelling. Float level and everything else is correct. I have had this rich idle problem since the day this carb was taken out of the box. I bought it brand new threw summit 2 years ago
ok, well this would be my biggest clue right here. besides the fact that checking the plugs is another good indicator of wether or not ur over carbed, or just jetted to rich to begin with. try this site for getting a base idea of what carb will work best w/ ur engine. http://www.timmcamis.com/carb_size_needed.html
if u do the math, most engines from the factory r maybe around 80% volumetric efficiency. a cam, some head work, and an aftermarket intake on a mild build will still only maybe get u to 90% efficiency.
if u like the carb, jet it down., jets r cheap. otherwise, start looking for a carb around 600 cfm... that ought to get u in the ballpark. gl