dual carb setup help

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2 fast z28

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hi guys just got the car running again tonight, what I have is a early 340 with 10.1 compression extreme energy cam and old offenhauser tunnel ram intake im running two 450 Holley carbs just had the carbs rebuilt by a very well know engine shop in my area now my question is im running a total of 28 degrees of timing at 3000 which I think im going to bump up to 32 after doing some searching the car runs good idling and revs are quick and not sluggish but when I go and drive the car and cruising 30 mph and then go and get into the throttle and it start to pop and bang and falls on its face what do I need to adjust to fix this problem any help would be great my fuel pressure is 6.5 psi thanks
 
probably want at least 18* of timing at idle, closer to 34* above 2500rpm

on the carbs undo the linkage and loosen the idle speed till its closed. from there set all your idle mix screws to 1.5 turns out. Now with your new timing adjustment start it and see what it does. increase idle speed equally, what you do to one carb you do to the other.
 
thanks for the info I first set total timming to 30 then checked float levels they where good then I turned all the idle mixture screw in and backed out one full turn reset both idle screw so they are the same started car felt good already went to back of drive way put it in drive and stood on the gas lighted the tries up with no hesitation wow I thought drove it around town night and day difference love the throttle response this thing has thanks for the help
 
no problem. Your total is still to low unless you have pinging. Also by checking total timing your not getting the full "timing curve". let it idle and see what its at, anything less then 16* and you need to re-curve the distributor, i bet it would like 20* at idle and 34-36 above 2500
 
oh ok so I can go more timing the dizzy is recurved I bought the kit from mopar performance and I do have the vacuum advance hooked up to I believe you said total timing should be set at 3000 I will try putting more timing in it and see how it likes that it isn't pinging yet I will report back when I do this thanks
 
i bet it will like it! and be careful on the vac advance, hook it up to a vacuum pump or something and see how much more timing its throwing in.
 
ok got out to the garage today messed with timing disconnected vacuum advance gave the car 35 total timing at 3000 drove the car and it likes that floored a bounce of times I her no ping got home let the car sit and pulled all the plug nice and brown looking looks like its liking the timing and running good thanks for the help
 
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