I have and Edelbrock 600 cfm carb(1405) on my souped-up 5.0 SBF. Got good heads....RPM manifold.....headers.....T-5 tranny.....snotty camshaft with 230-236 duration @050 on a 108LSA. Runs pretty dog-gone good/idles @750 RPM fine But........while driving under 20mph in 1st or 2nd gear it wants to start "motorboat'in"(that's how I describe it!) give it a little more gas and it calms down. I can kick-in-the-clutch and clean it out a little and that helps but ...if I don't accelerate it does it again. I THINK....if I go to a stronger metering rod spring that might smooth it out some. What's your thought? Also don't Eddie carbs usually come jetted pretty rich?............Maybe I need to lean it down some, I just want to lean it so much 'I burn stuff'! Thanks for all your input 6sally6 PS........Don't need any" you-need-a-Holley" comments because THIS is what I got.