tunnel ram issues

ok I have a 71 dart with a fresh built 340 and im doing some final tuning on it well every thing was going good I have a wide band 02 sensor in the exhaust numbers are looking good so I pulled plugs to check the out and I notice that the two from second from the front of the motor should be 3 and 4 cylinders are a little wet but the plug is brown and it smells like gas so I checked the idle mixed screws again and they are the same as the rear carb so I started the motor and sprayed some water on the header tubes and I notice all four front cylinders were colder than the rear four cylinders the water stayed on the tubes way longer than the rear would just boil off idle the wide band it saying 13.4 cruise 14.3 and wide open throttle 11.8 should be pretty good but the idle temp on the exhaust has me stumped I will post a pic of the intake it will make more sense will I say the front four and the rear four the intake is a old offenhauser intake and it splits the motor in two basically they don't not mix like most tunnel rams any help would be great