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Old 07-07-2010, 03:44 AM   #1
derek6787
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Join Date: Jul 2007
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new truck....timing

Hey guys I just got a 1971 Chevy Shortbed 2wd Super Cheyenne. It has a mildly built 454 with some bolt ons as well. When I got the truck it wouldn't hardly idle. I adjusted the fuel screw on the carb and the timing by ear. I wan't to get the timing set right though. So where on a big block should it be timed? About 4 degrees advanced? Thanks for the help and I will post pics asap!
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Old 07-07-2010, 03:38 PM   #2
Wrenchbender Ret
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Re: new truck....timing

I would set it at about 6-8 degrees unless it has a mild cam in it. In that case i would try about 10 degrees. If it pings on a pull, set it back a little. Screw the idle jets out a little & turn them in slowly till the engine starts slowing down. Then back it out enough to smooth it out again. usually about 1/2 turn.
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Old 07-07-2010, 03:47 PM   #3
geezer#99
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Re: new truck....timing

What kind of carb are you running. Set the timing at 10 degrees first. Your motor will speed up a bit and then adjust the idle screws. Got a pic maybe. Easier to diagnose!!
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Old 07-07-2010, 07:14 PM   #4
derek6787
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Re: new truck....timing

I"m running a holley. Dont know which one havent had much time to play with the truck yet since I got it. I will post some pics hopefully tomorrow so that it'll be easier to diagnose lol
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Old 07-07-2010, 07:50 PM   #5
geezer#99
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Re: new truck....timing

All the holleys idle bleeds adjust the same. One on each side. After you set your initial timing to 10 degrees adjust the idle screws. Best to use a vacuum gauge if you have one. You want to attain the highest vacuum reading. Adjust one screw either in or out to get a better idle and then adjust the other one. Go back and forth till it idles smoother. Slow down your idle again if it's idling faster and fine tune your idle bleeds a touch more if needed. Don't worry about how many turns out the screws are set at. 1 and a half turns out is a good base to start at. Go easy on the screws if you turn them all the way in. They're delicate. Have fun.
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