tunnel ram issues

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2 fast z28

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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
 

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are you running a pcv on one of the carbs, this could lean one side out?
 
ok went out to the garage used a temp gun this time and checked bank 1 of the engine front two where 240ish and rear two where five hundred after like two minutes of running so I called my engine builder and we where talking and he said sounds to me like u have a vacuum leak and leaning out that rear four cylinders he said try turning out the idle screws on the rear carb till the temp start going done and I did that it helped some still high so got the old brake clean can out and started to spray sure enough I spray the rear area by the carb and the idle changes so its ether my carb gasket the carb adapter gasket or my vacuum port where I draw for my brake booster. im thinking its the vacuum port I will do some more testing tomorrow and will update #-o
 
Very good. Do not adjust the idle screws so "they are the same" physically. Adjust them so the engine RUNS. Not being familiar ( I THOUGHT there was a small interconnect or balance port on those ) you may have to 'rig' a vacuum gauge if necessary, to each one in turn. You should however be able to do this by ear and the tach.

Make sure you get the timing FIRST

Make sure the engine / carbs is fully warmed

You are / are not running power valves?
 
I am running power valves now the only vacuum port on those carbs are for the vacuum advance on the metering block
 
Determine if the power valves are opening. Also, is the throttle butterflies closed enough to keep the idle "in" the transfer slots? Don't those carbs have a PCV valve connector in the rear, in the baseplate?
 
well boys after a few nights of working on the car found the problem the place I have the carbs rebuilt messed something up I had two things going on first the power valve was double gasket so I removed one of the gaskets second I found that one of the butterflies on the carb was installed backwards so it would not allow the butterflies to close all they way. got that all fixed tunned the car again and boy does it run awesome thanks for all the help :burnout:
 
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