carb prob ??
 

i have a chevy 413 and has a 750 hp holley carb and the problem we are having is it will drop rpms after the temp gets to 180 degrees in gear only but runs perfect till we get up to 180 any advice on this thanks or if u need more info will let u know

Could you be alittle more specific about your problem.
What do you mean by 'drop rpms'?

when in gear and u push throttle going up against converter and let off of throttle drops rpms down to around 400 only does it when temp gets to 180 other than at that temp it dont drop rpms thanks for any help u can give

I believe you are tuned to the wrong temperature. I've had many an engine that runs great when cool but the real world starts at 160 and up.
JMO Dave

droppin idle speed
 

don't know if you have a spacer under the carb to isolate from the heat..might help. I have seen the fuel in the carb heat up and expand and dribble from the boosters and drop fuel into the engine..essentially causing a flooding situation. Look into the carb when the idle is dropping. Watcha see?