I have a '71 360 in my '74 'Cuda that I rebuilt last year and has been running since this fall. The crank was sent out for machining and a good going over by professionals. I have a 650 double pumper on top and a .454/.454 cam in it. It runs well and idles nicely... however once I get out on the road and punch it, the whole car gets shaking. At about 3500 rpm it really starts rattling and the pistol grip starts shaking like crazy.... Its annoying enough that it makes me want to stay within 20 mph of the speed limit... The harmonic balancer is the one that came with the motor and hasn't been touched. Im wondering if its not balanced anymore since the crank was machined and if that is the problem. There is also an aftermarket Vintage Air air conditioning system on the engine and a cast iron pulley that bolts onto the pulley slot on the balancer. Im wondering if that has some thing to do with it. Any ideas?
360 Vibration Problems
- Thread starter JedIEG
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moparleo
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Original flywheel ? Same pistons? The 360 is externally balanced. That means that the harmonic balancer and flexplate/flywheel are necessary to balance the engine.
Also check the trans mount and u-joints.
Also check the trans mount and u-joints.
74 challenger
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i was always told if the shifter shakes its the tranny or drive line.
Chryco Psycho
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everything needs to be balanced in one pkg so the crank ,rods ,pistons, flywheel ,balancer & brgs all have to be there to properly balance everything . We had a crate 360 from Mopar & it shook horribly at about 2500 up & it was so bad we had to pull the engine & rebalance everything , Mopar probably used a much lighter aftermarket piston & did no balancing at all . The fly wheel is critical , it has to be a balanced flywheel for the cast crank & the offset weight is still dependent on piston weight so that is the first place I would look !
moparleo
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Not that hard. Just give your parts to a shop that has the experience and expensive equipment to do it for you. Its only money.
Like going to the doctor with a problem. He can tell you what he is going to do, so you understand, but not so you can do it yourself.
Like going to the doctor with a problem. He can tell you what he is going to do, so you understand, but not so you can do it yourself.
moper
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Does it shake when you're driving, or when the engine is running, or both? When you're driving, can you make the vib go away by pushing in the cutch pedal or taking it out of gear? What flywheel was used when the new engine was isntalled? What was in there before the 360/4sp?
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