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Discussion Starter #1
i have a terrible vibration between 800-1300 rpm. compression is equal=165. carbis good, changed plugs and wires and ing. it doesnt vibrate while crusing, only at an idle. seems to get worse when the engine is warmed up and driven 30 miles. vacumn is good. im cnat figure it out. feels like somethi is out of balance. any ideas.
 

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Could be a miss fire on one cylinder. Easy check: take your timing light and go from one plug wire to another with the pickup clamp. Stay on each wire for about a minute or so. Point the light at the fender. Does it skip some flashes? Could be a bad wire, cap or rotor.
 

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What you are describing sounds like what I would call a "rough idle". It's likely ignition or carburetor related, not something out of balance. You should be able to tune that rough idle out of it, since the compression test doesn't show any valve problems. Give the old girl a good tuneup (points, plugs, condensor, rotor, cap, timing), and adjust the idle air mixture screws. Let us know how you come out.
 

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I thinking the same as Dodgestang. Sure sounds like a performance cam. A little more info is needed. Is the engine suppose to be stock or what?
 
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Discussion Starter #6
glad your all willing to help me figure this out. bought the car from a little old lady, appears to be stock, good vacumn. when i bought the car it had one bad cyl. changed plugs and wires. made it better. ok, after 10,000 miles same problem, so i replaced the plugs, bosch, and put a new set of taylor spiro wound wires. made it better. the motor will idle at 500-600 rpm better than 900 rpm. does seem like it has a big cam in it but the vacumn is to high=20hg. i rebuilt the carb, autolite 2 barrel, then changed and rebuilt another carb, autolite 2 barrel. the cap and rotor were changed, blue streak. screwy thing is that it cruses great. takes off like a bat out of hell. i would think that if it had a big cam the vacumn would be down. and it gets 16 miles to a gallon. ill try putting my timing light on each wire and see if i can find something, maybe theres something i the distributor thats messed up. great site but how do you get notified if someone responds to a post.
 
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