ok guys heres what happened. i took a carb off my 53 ranchwagon EDELbrock 1404 and put it on the nova. which has 1405s on it. started the nova up and let it idle for atleast 5 mins. never turned red. good found which carb on the first try.put the 1405 back on the nova so i could move it until i had time to rebuild it.started it back up to check for leaks and this time no red header, wtf!!!!!!!!! oh well at least its workin like its suppose to..lol it has ceramic coated headres on it. and on the side that turned red the coating is off it ,long story. anyway,that side runs hotter. we tought that because the coating is gone here comes heat. but atleast now its not turnin red!!!! could i have jared something loose like a peice of trash when i was changing carbs around?