i have a problem my motor is new i did the break in and it ran great ,now today i went to run it and it will not idle i have tryed resetting idle mix but as soon as i try to idle it down it dies, it runs good on the high end i am stumped it only has 7or8 tanks threw it can anyone help, gary

Could be the plug, break-in is really hard on them.

Yeah I would agree. Replace your plug and see if it runs better

If a new plug doesnt get a better idle, then I'd suspect the idle mixture is too rich. You may try leaning the idle mixture before switching plugs. Either way, once the engine will idle reliably, re-set your main needle to peak performance and slightly richen, then re-set your idle needle so it produces a nice crisp transition to WOT. I usually set my smallblock carburetors to stall out at about 3 seconds when the fuel line is pinched.