smoking.....?

ok bros a friend of mine who lives too damn far away for me to travel and look at his vehicle has a problem.heres the low down.his small block chevy race engine ,high compression,roller ,etc is smoking like out of the blue,he had it re rung last fall/no major high rpm passes....crate world motor about 2 years old ...he said his idleing has jumped up to 1500 and it usually goes about 1100..i cant understand the smoke deal though/although he did run some pump fuel in it at low rpms cuz blue/purple fuel not available..could he have pulled rings out of it or is this something from unleaded fuel.?will this smoke pass..i never ran shit fuel in a high comp motor so im not sure.thanx.

Has the timing been screwed with? (ie advanced?) Maybe the combo of that and the low grade fuel has caused detonation to burn a small hole in one of the pistions? Hard to say without being there and actually looking at it.

i agree.what sure fire way can i tell him to check for detonation/as in a quick answer?

one more thing he has like a 600 plus solid lifter roller with 14 to 1 s or sumn what should he be idling at?rpm that is.......i forget duration wait its a 637 lift with 276 duration.

Well, I would have him run a compression check first, see what the numbers are and go from there. It seems odd that the idle RPMs picked up all by themselves. That is why I asked if the timing had been screwed with.

Is it really blowing blue smoke, or is it just running richer than normal? ie. black smoke

he seems to think its blue........they just changed the cam a while back....think it jumped timing.?....could this happen with the fuel and could the lead/unlead cause some type of mixture confusion in the engine.....although i think you could be right,might be black smoke as in dark

Could be a cracked intake/head. Sucks in the air from outside idling high, like a vacum leak, oil gets by the valves. Do a compression test, then a vacuum test it that doesnt show anything.

would that increase timing?1100 to 1500........how hot can his go?