After swaping over a 04STi long block into a 02rs, and making some major modifications I am having a great deal of trouble getting her to stay running and running well. Im getting a missfire code on all 4 cylinders, but everything is in place ( sensors-vaclines-ect. ) Below is a the list of mods that are done to the car. Could all of these things make it run this bad with the stock ECU?

Its a 04STi long block with less than 1000 miles on it w/stock STi ECU
-STi FBW throttel
-STi fuel controll moduel
-WB 255lpm fuel pump
-STi stock yellow injectors
-vf39
-TXS FMIC
-TXS 4inch DP
-3inch catless exhaust
-Tumbler Valves have been deleted ( rods and bars w/port n polish ) with APS TGV blocks installed to prevent cel
-no rear 02 sensor

yes i know i need engine management desperatly but it should run and idel?....just rully poorly

-I know fuel presure is good guage says 40+psi at idel...fuel lines are not backwards either
-I know the MAF and front 02 sensor are good
-I know that there is no vac leeks.....at least my Defi boost guage tells me that
Im not throwing any codes for bad sensors. Could it be a crank position sensor, cam position sensor, or sumthing like that? I do have a friend with a 04STi to swap sensors with to check them, is tha my best option to find the problem?

PLEASE any tips or imput would be greatly appreciated

you could still have a vacume leak ...
the boost gage woulf not tell you if its sensor was after the throttle plate like it should be
(remember all the air that goes though the maf needs to get to the motor no more no less ..)