Vent Tube Question

[BDR879]

Experts,

Have been doing a bunch of reading and noticed that Holley / Quickfuel, etc sell vent tube extensions and am curious if it would stop engine bogging when stopping.

In particular, when I declerate on a downhill incline, the engine bogs and almost stalls. Same thing sometimes happens when I slow down though a turn.

I am assuming it is a result of gas sloshing out of the vent and into the manifold causing a rich / flooding condition.

Will taller vent tubes help?

I have also heard of folks connecting the front/ rear vent tubes together with tubing an drilling vent holes in the top.

[blykins]

Where do you have your float levels set?

[BDR879]

First of all, I'm running a Quickfuel HR780. When the engine is running, fuel level is 1/2 way up the sight glasses. This is the way it was set up by my engine builder.

[Bobcat]

Try lowering the rear float level some . That should help on the bogging problem under hard braking . If that float level is too high , the fuel will spill out the vent tube directly into the secondary butterflies .
Had that problem at open track Friday at SAAC 36 and cured it by doing that .