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!!!!!!!!!