you don't have to hold crack in longer than 8 seconds, 5 is good enough 8 and you absorbe pretty much all of the crack in the 'smoke' its actually vapor particles not smoke btw, fun fact =p aswell as try not to smoke it like you do weed as in flame on rock, use flame near rock, melt, tap the rock for 1-2 seconds every now and then for alittle combustion and voila, but yeah generally the shorter the pipe the better for crack. - i smoke 20-40g a month THE ONLY EXTRA 'HIGH' you get from holding it so long is oxygen deprivation, trust me. also, by flame near rock i do mean NEAR, not always on it, but goddamn near it, i actually love to smoke my fishscale with hempwick =p if you give that a go, you'll notice you'll never fucking cough again atleast until the hits over

on a side note though, you shouldnt be taking as big a hits as you can handle as you CAN od aswell as your lungs have so much surface area that can absorb the cocaine, you wana take medium hits (youll still blow decent clouds but itll go alot further and you'll get alot higher) if you want to use a bong either make one of those water bottle / can pipes or buy a SMALLbong (they make plenty of those nowadays) and you can buy a large cone bowl and either stuff it with brass screens OR they make them big enough if you really wana stuff them with choreboy - i haven't tried one of those tiny bongs for coke yet but now that ive mentioned it, its definately on my list to try, never really thought about it till now BUT THE PROBLEM WITH USING A BONG TOO is you can't collect that yummy resin after youre done