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My car is demonstrating a tendency to die on hard braking. My understanding is that causes typically fall into one of two categories:

1. fuel sloshing over from rear float
2. vacuum steal from power brake booster

My cam is a fairly aggressive Comp Cam 292H. I'm generating 7 inches of vacuum at idle and at least by my gauge there doesn't appear to be any vacuum leak. Idle speed is about 800 rpm. With that low vacuum I would think I would be at risk. I haven't noticed anything abnormal about the feel or performance of my power brakes.

The rear float is set at a level just a hair below the site window. I know I've got some heat soak and percolation issues going on at the carb. The stalling seems to have gotten worse as the weather has gotten warmer. Could heat, evaporation and condensation of vaporized fuel be contributing to the problem?

First, I'm going to try dropping the float just a bit. I've also got plans to add a carb spacer but that plan is on hold while I decide what to do with my intake and air cleaner.

Any other thoughts or recommendations?
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Under hard braking, fuel is sloshed forward
in the rear float bowl, flowing through the vent, dribbling onto the butterflies and into the intake, and the carb suddenly goes way rich, flooding the engine and it quits.

As you suggest drop the float, you probably don't kick in the secondaries very often anyway.

Another trick that has worked for some people is extending the vent tube, or connecting the front and rear together so fuel sloshes into the primary bowl.

My car was doing exactly the same thing.
Engine would cut out during low speed aggressive braking.
I also have a fairly wild cam fitted.
I made up an Alloy vacuum bottle of about 2 litres capacity with an in & out fitting.
Vacuum line from engine to an Earls check valve, (one way) before the bottle.
Then a short hose from the bottle to the brake booster.
Vacuum bottle is mounted in front of the booster.
Problem solved, never had the engine cut out since.
If the centrifugal advance mechanism were sticky (and I'd be surprised if it isn't) then when you slowed down suddenly your Pantera's motor would be trying to idle with too much ignition lead.

If your motor is equipped with egr this could also be a sign of an egr system that isn't shutting off at idle.

Typical problems for an unmodified 37 year old 351C.

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