Just got my 89 GT Convertable back on the road with newly installed Edelbrock Perfomer RPM heads, a B303 cam, stock intake and aluminum 1.6 roller rockers. The car will idle ok, but sometimes surges drops to 500 or 600 rpm then back up to 1200 rpm) when I push in the clutch and let of the gas. Occasionally this is so bad, that it stalls the car. I real pain when I'm just downshifting to enter a turn. I was told that this is a by-product of the cam and that playing with the idle adjustment was the only POSSIBLE solution. Any help ou there? Thanks