New 408 stroker runs rough at idle

I already pinched off the vacuum line to the pcv valve. No changes. I figured after hearing you have to drill holes in the throttle plates, I just set the idle speed to where it starts to smooth out, and turned the mixture screws out 3.5 turns. However I notice it seems to bog down really bad when you first step on the gas, and sometimes you’ll hear the exhaust pop a little bit, And then it suddenly jolts forward and does just fine until your at another stop. You can see white smoke coming out of the exhaust at idle. I then decided to drill holes in the throttle plates, started at 1/16 and worked my way up to 3/32, and now it’s to where you can have the idle speed screw to where it’s turned all the way down and it idles at 1k rpm, and the mixture screws still do nothing.