Do i need injectors
 

I have an 89' Mustang GT that was extremly fast for only having a few things done to it. But this winter i wanted to rebuild it and get more power because it had many miles on it and i just need more power. Anyway i took out the motor, honed it, cleaned it ported and polished the heads and unpper and lower intake, got a 70 mm throttle body with egr backplate, i pu in keith black 12:1 compression pistons with sealed power rings and all new fel pro bearings and a nice big comp. cam. All of it was done correctly and everything is new inside so it should be fine. one problem, i doesnt idle. I give it just a little gass and in the upper rpm range it sounds good and runs powerful but when i let it go to idle it shakes and stalls. i took it in and had it timed then it worked good but next day it didnt. i have the stokc injectors in it, do you think i nneed bigger or could the problem not be the injectors and more like wires? -thanks

First thing, how big is the lift on the cam, if it is too big it will stall out. Just porting and polishing the heads and intake won't help with a big cam. Are they stock heads or aftermarket, and same ? with the intake. To get the most out of a big cam, you need high flowing heads and intake, AND you need bigger fuel injectors WITH a calibrated mass-air AND a bigger fuel pump AND an adjustable fuel pressure regulator. ALWAYS if you are going with a big cam, make sure you have heads and intake and all that other stuff to make sure enough air and gas go into the motor.

You are still well with in the range of the stock injectors. What cam did you install?

Dont let anyone tell you, you cant make good power with the stock injectors and heads. My car hauls @ss.

Did you adjust your TPS?