I had been on crack for almost a week, not alot but at least once a day! I stopped sun 25th at 3:30pm and have an instant saliva test on weds 28th at about 2:30pm, that will be 71hrs since i last smoked will i pass the instant saliva test?

Sorry you have such a hard time with this, but you need to get help so you can kick this stuff. Don't worry about the test, worry about getting into a recovery facility or organization before it destroys the rest of your life.
You have been on it for much longer than a week so stop lying to yourself and get help.