70Charger493C.I.
Member
Hi, I have a 440 stroker (493) that i just got done building and i have a bit of a problem. Seeing if you guys got some good information etc about this issue. Ill tell ya the specs first. Indy EZ heads HUG 4950 fully ported to a Port matched Indy intake IND 440-I4-2D. When engine is over 3000 rpm's for less than 2 min fully warmed up 185-195F the headers glow a dull red. The spark plugs read this: Inner 2 cylinders on both sides read extremly rich and are dark black. The two outer cylinders read a dull white color. Not too lean, but its something to be concerned. The headers are hooker super comp 2inch primary tubes. And the engine has total timing at 36 degrees and is fully advanced at 3000. MSD parts. and running NGK plugs that are a good heat range. Also have tried champion plugs as well. The carb is a Quick fuel 950 Q series. I have been tunning the carb in etc and it has done nothing. idle screws have tried at 1 1/2 & 1 3/4 turns out and does not make a difference. Even tried goin with bigger jets etc. 86 in front and 88 in rear. went back to stock. 76 and 86 in rear now. Starting to think maybe the intake could be possibly be the problem. Being i do have a dual plane my intake runners are a different length goin the heads considering a single place intake has mostly all same length intake runners etc by the designs of both of them. Me and buddy have been doin some research and i dont know if this correct or not: A carb intake has grooves in the plenum portion under the carb. These grooves cause turbulence in the plenum. This turbulence causes the air/fuel to mix there by equally distributing among the cylinders.While a fuel injected engine wants no intake turbulence, a carb engine requires this turbulence. With out it, the fuel will pool at the bottom of the intake under the carb. It will then pour into the center four cylinders, leaving mostly air to enter the outer cylinders. Pull the carb off and check the intake plenum for those grooves. If it's smooth, there's your problem? There's a very good chance they were removed while porting and that ruins the intake? Hopefully you can give me a good sense of direction on this issue and also to see if this information if correct or not. Thanks for your time and hopfully i gave you enough information to use a good guess on what the problem is.
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