Personally , I think if you're gonna do crack , you may as well do intra-vienus novacaine . Better buzz , goes further , and best of all , the comedown can actually be quite a nice experience as well . (no palpatations , gives very light comedown with kinda stoned effect and good concentration - I find crack comedowns horrible , but mainlining coke fixes that ) . (Just make sure you get it all in the vein or you'll go completely numb in your arm/whatever . - and if it feels too intense with the plunger only half way down , for christs sake take it out - I know thats a hard thing to do , but you could quite easily have a stroke if you dont )
p.s though I think mainlining coke is better for you than smoking crack , I think they're both incredibly stupid things to do if you have control of your drug usage without them.