Quote:
Originally Posted by steve s
Dan,
You may think I'm nuts, but what heads are on your various A's? Did you try a different carb, or increasing the throttle/idle speed, or opening the GAV?
Steve
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Quote:
Originally Posted by Dan/Kzo
... #8)standard head currently using Zenith, but have also had Marvel. have not really changed throttle or gav.
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The ultimate source of that deceleration vibration--whether it's excessive or not--is the pistons' sudden direction reversal at the top of the compression strokes BUT without the normal cushioning air/fuel charge in the combustion chambers. Thus, it should be worse with the low-compression stock heads and carbs that might be a bit stingy with idle fuel charge--hence the suggestions to increase idle throttle setting or to open the GAV. I'm not sure but I doubt that the Marvel would have the fuel supply problem. So, other than the possibility of high compression heads on your comparison vehicles throwing off your perspective, I'm now at a bit of a loss. Maybe the guy who implicated the rear end knows something I don't (quite possible!), but it seems to me that if that's the problem some noise should be evident from back there, and similarly for the U-joint. I don't understand how any sort of rotational imbalance could give different results depending on deceleration--that effect should just depend on rpm, I think.
Another possibility that occurs to me is that there might be something else on the truck that is of fortuitous size, shape, and looseness such that it resonantly couples with a normal amount of engine vibration to give an abnormally larger total perceived vibration. As I sit here visualizing the truck, that doesn't sound too far fetched--no offense intended.
Steve