Author Topic: Vibration and Balancer/Flywheel question  (Read 3596 times)

Offline covert

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Re: Vibration and Balancer/Flywheel question
« Reply #15 on: January 05, 2008 - 05:38:28 pm »

Actually, when I swapped engines, I swapped the whole engine / tranny as a unit.  So the 400 and its transmission stayed together as a unit, and the 440 and its transmission stayed together.

I don't know if the 400 had a forged crank, but the next time I see it (don't know when that might be, but I still see the guys sometimes who have it now) I'll see what kind of balancer it has on the front.

The guy I got the 440 from was seemed pretty honest to me (at least, everything he said turned out to be true, so far -- You never know though)   But he had said that it was a real recent, newly rebuilt transmission.  And it seemed to be -- the paint was still clean on it, and the rebuild label from the place he got it was readable and not even dirty.  When I think back about the timeline of when he said he replaced the transmission, to when it parked the car, it might have been that he replaced the transmission, started to get a vibration, then gave up trying to figure it out and parked it.

The vibration might not have been as bad for him, cause it was in a much bigger car, and it turned out when we took it out that he had a broken motor mount.  (I don't know -- just guessing)

When we were driving the car around before the swap, we never noticed it, but that was mostly around the car yard and the shop (cause the car was running of a 5 gallon gas can in the front seat, when we got the car the gas tank had a leak, which the seller had told us about)

I'm honestly beginning to believe that the 400 we pulled out might have been a stronger motor than we may have thought -- it may have been a sleeper.  It didn't look like much, but little bits of stuff here and there lead us to believe that the guys who originally put it in the car knew what they were doing, just weren't into making anything look nice.

Besides, who's going to go through all of the work to put a 400 into a 318 Barracuda unless they really know what they're doing.

Offline Challenger_7

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Re: Vibration and Balancer/Flywheel question
« Reply #16 on: January 14, 2008 - 12:55:48 pm »
Hi. I went through a similar problem and left nothing un-checked on a 400 engine fitted in my 71 Challenger coupe. At the end of the day, it turned out to be the wrong converter. I had one which was externally balanced, and should have one which is not. Once I changed it, all my worries simply went away. In the meantime I also changed my flex plate to a B&M one which is supposed to help reduce such vibrations.
I had this discussion held on Dodge Charger forum and learned a lot from it, including how to check for the correct damper. If you are interested in learning more about the details, check it out here (,22287.0.html)
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