Pulled my heads off and sent to the machine shop for pushrod clearancing. Was told that the intake runner showed significant reversion near the intake valve. The intake manifold looked new if you viewed the runners from the carb flange. The intake runners on the intake had a slight gray appearance where they meet the head. No black soot. Does this limited information sound at all concerning? Or should I not be concerned?

493 Indy EZ CNC 295's
Indy 4150 intake
1.5 rockers
Solid Roller
.621 lift at the valve
272/276 @ .050
Intake closes @ 64 ABDC
Exhaust opens @ 66 BBDC

Whats the lsa and where is it in at?

To answer your question... how much is too muck...I have no clue, We had signs with a 280@.050 cam 107 in at 103 but not that far into the port, it stoped at the top of the short turn, new cam is much smaller 260@.050 106 in at 105 with more intake ratio and cant see any signs at all so far

Think you might be leaving some on the table , try advancing the cam 4* , or back some lash off the intakes.

usually you only see that when cam is retarded on street style stuff--race engines can't say I have ever noticed it. Saw a 318 one time with a street hemi grind in at about 115 and it was GREY all the way to the carb base --

i was told straight duration cams are worse for that. i do know i had to retune my carb with a straight dur. cam.