stylelined

Hi Mopar folks, I have problem with my 1975 Duster Custom 318 engine w/aut trans. Purrs fine on idle and during acceleration but on highway speed (40 - 50 mph ) it feels like it misfires or burbles, especially when I slightly ease on the pedal. I have new carb, Carter BBD, and the distributor should be very good. As soon as I press again carefully on the pedal it accelerates but when it reach the speed related to the pedal position it starts again to go like it should misfire. Does it have to do with the vacuum advance or otherwise with the ignition or could it be related to the position of the metering rod positions, I have not touched them yet. I will check the vacuum canister tomorrow also.
It drives well on low speed, up to around 35 - 38 mph. I have also noted that there is a delay when I'm taking off from traficlights,feels like it do not react immediately when i press the pedal but accelerates good when it starts to.

TVLynn

I would start with the timing of the distributor. Disconnect the vacuum advance hose and plug it. Check the timing set to 10 deg BTDC. Next MAKE sure the vacuum advance line is hooked up to a ported vacuum source NOT full time vacuum.. See how it runs
Make sure the plug wires are on the correct plug

stylelined

Yesterday I opened the distributor...or...took of the distr. cap. Put the vacuum hose in my mouth and created some vacuum and the plate moved and stayed in place when I held the vacuum...But..one funny thing I noticed, when the plate where the pic up is mounted moved, it did also move up and down several millimeters when I touched it with my thumb. When I lifted it, it came in contact with the reluctor and when I lightly pressed on the pic up the air gap was widened. Is there something wrong there. Could this affect the ignition at highway speed.
Checked around at Ebay and found several choises for new distributors. There is one interesting, a company named Performance Distributors sells one called Dodge Tri-Power Ignition at USD 309.00. Anyone having any experiences with this one. They also sell another, Small Block Dodge DUI ( compare to GM HEI distributor )
Or should I stay with rebuilt original.

TVLynn

It will move around some.. Depending on what you are going to do to the engine? A stock distributor should work fine