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Reply to "Grey Smoke During Deceleration"

The connection to the carb needs to be higher then the connection at the valve cover otherwise you will siphon oil into the intake manifold.

This is a common issue with Fords and their PCV system.

You also need a proper operating PCV valve in order to apply negative pressure (vacuum) to seal the piston rings.

The oil filler cap also needs to be vented as the fresh air source into the PCV system. If it isn't, for sure you are siphoning oil from the valve cover. Depending on the cam profile as far as how much idle vacuum it gives you, it is possible that you may need to restrict the fresh air intake.

I had to do that with my Weber set up. Webers aren't often run with a "closed" PCV. In order to maintain a decent idle vacuum, the air intake needed to be restricted.

As I said previously, it sounds like your rings are not completely seated and it may be related to a non-functioning system.

Put a clean white t-shirt over one of the exhaust tips while the engine is idling. See if there is oil residue on it.

You can get exhaust smoke from the carburetor as well. Usually the accelerator pump but it could also be that the float level is set just a little bit too high.

With a Holley carb and E85 fuel, you need to set the fuel level in the bowls about 1/8" lower then the edge of the site plug hole.

With the current E85 fuel, the Holley fuel level setting instructions ARE WRONG. You will be set too high if you follow them.

Last edited by panteradoug