Posted July 22, 200420 yr comment_88527 This does not seem to be a serious problem, but when I am going down a hill allowing the car to coast (no gas being supplied) it starts to backfire at around 2200 rpm or approx 55 mph. If I give the car just the slightest bit of fuel it stops. The backfire is not very loud but it is annoying and does not seem proper. Also, when I come to a stop before I start to move again I sometimes have to tap the gas a couple of times to get the rpms up above 1100, if I give it steady throttle from idle (900rpms) it chokes and dies. Ive checked my timing, running at about 20 adv and my plug gap is correct. Ive switched over to an electronic ign. from a later z and am using a gm ign. modual. My carbs are dual dgv webbers that seem to tuned correctly, but i am not sure. Any suggestions other than ditch the carbs for su's? (wish I could, can't afford it yet) Thanks, Dan Link to comment https://www.classiczcars.com/forums/topic/12616-backfire/ Share on other sites More sharing options...
July 22, 200420 yr comment_88529 Make sure that they (the DGV's) close completely when the engine is idling. I had a similar problem when I had one of those on my 521. Also, 20 degrees sounds like a lot of advance. Link to comment https://www.classiczcars.com/forums/topic/12616-backfire/#findComment-88529 Share on other sites More sharing options...
July 22, 200420 yr comment_88571 Valve adjustment ,worn plugs or wires are just a few Link to comment https://www.classiczcars.com/forums/topic/12616-backfire/#findComment-88571 Share on other sites More sharing options...
July 22, 200420 yr Author comment_88573 Thanks for the help guys. A friend of mine said I may be running too lean. Turned out the air fuel adjusters 1 turn each and presto, no more problems. Thanks again for the help though. Link to comment https://www.classiczcars.com/forums/topic/12616-backfire/#findComment-88573 Share on other sites More sharing options...
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