The problem with the TQ (or any metering rod carburetor) is that with a large camshaft the vacuum drops to the point that the metering rods "jump" and the idle mixture is very tough to get right. The Edelbrock style carburetors are "better" at combating this, but "I" have never been able to tune that out of a thermoquad. Maybe somebody else has and will chime in with the magic secret.
