We dropped my new 402 iron block motor in this week and after getting everything together #4 injector is not firing for some reason but all the rest are firing fine .
I swapped injectors around and its not the injectors and im getting the same readings on all the injector plugs .
We changed the pcm to see the new injectors but the car bucks like a bronco and wont idle .
Im getting spark through the coil but no fuel to #4 cylinder.

Im trying to get the car running so i can take it down and get it tuned .

Any thoughts ? ,, am i missing something between the LS1 and the new iron block ?

It also seems like #4,5,7 and 8 cylinders are not running at the same tempature .
#1,2,3,6 header tubes are hot as hell and the others kinda warm to the touch .

Please help

 

The hotter/colder situation is most likely related to the hotter cylinders running more lean than the others. As for why it's happening, if you're sure you're getting spark to the plug (use an ohmmeter on the plug wire to make sure), then I would think it would be something at the fuel rails that's preventing the fuel from getting to #4. Since you switched the injectors around and nothing changed, it's obviously something before that. My best guess would be that something in the rail is getting clogged up. I'd also check to make sure you're getting adequate fuel pressure by hooking up a gauge to the end of the rail.