ok..... plz keep in mind that i am new to cars and don't know a hole lot about then..... ok well... my 1977 280Z needs to crank over a good 30 sec. before it will start. But wait theres more.... When i go to give it gas its idle drops a little then has extrem diffaculty reving up but afer it passes about 3500 rpm its fine until it goes back under 3500 rpm..... Can any one tell me why this is happing and i just replaced the fuel injectors.... Thank you for your time!!!!!!!!!

If you have e.f.i., it sounds like the AFM isn't working right. Sounds like it's running really rich.

Check the exhaust smell, looks.

If the AFM is not working i have 3 or 4 spare with a few other spare parts

Sounds like you need to go through the cold start system. Thermotime Switch, Cold Start Valve, Air Regulator. Also check the temperature sensor. Sometimes, it's just a case of bad connections. If the cold start valve operates (bad thermotime switch) or leaks (bad cold start valve) after the car starts, that would account for the richness and difficulty accelerating. Do you have a Factory Service Manual?