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Dead Parrot · 07-12-2017, 10:33 AM

Did you set the float levels in the carb prior to installation? They are usually wrong from the factory.

Make sure your power pistons are moving freely. If one is sticking down, will cause a lean condition at high throttle.

Vacuum advance should be out of the picture at or near WOT, especially if your advance pot is connected to manifold vacuum. Make sure there isn't some kind of restriction in the hose that is causing the pot to keep vacuum near WOT.

Idle mix screws are out of the picture at WOT.

What rear end ratio do you have? It is easier to lug the engine with a manual.

As a test, set your initial timing to 0 and see if the pinging stays. If it does, might double check the exhaust system for subtle leaks and loose brackets. Several times I have thought I had a motor problem when in fact I had an exhaust system issue. A small leak might not be heard at low power and become much louder near WOT.

07-12-2017, 10:33 AM	#10
Dead Parrot Registered User Join Date: Aug 2012 Location: Oklahoma City, OK Posts: 2,496	Re: Recurring Crate 350 Gremlins Did you set the float levels in the carb prior to installation? They are usually wrong from the factory. Make sure your power pistons are moving freely. If one is sticking down, will cause a lean condition at high throttle. Vacuum advance should be out of the picture at or near WOT, especially if your advance pot is connected to manifold vacuum. Make sure there isn't some kind of restriction in the hose that is causing the pot to keep vacuum near WOT. Idle mix screws are out of the picture at WOT. What rear end ratio do you have? It is easier to lug the engine with a manual. As a test, set your initial timing to 0 and see if the pinging stays. If it does, might double check the exhaust system for subtle leaks and loose brackets. Several times I have thought I had a motor problem when in fact I had an exhaust system issue. A small leak might not be heard at low power and become much louder near WOT.