Anybody have a pair they want to part with? Time to block those crossover passages. I'll use a different year than '49 but...well, you know
If you are not worried about the engine swallowing the pennies and causing internal damage, by all means use them.
Otherwise all that I have ever done is bend up a thin piece of (tin can) sheet metal that can be slid in to install or removed if not wanted without removing intake.
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"RalphG", it sounds like you're one of "those guys" who think the Ford engineers knew what they were doing. I'm one as well.
I don't see why this is necessary except for an all-out race engine. The proper manifolds for those don't have a provision for manifold heat anyway, so why bother?
I'm sure this question was asked many times, so what is the purpose of blocking off the crossovers? Less heat on the carb?
The pennies in the manifold reminded me of to two dimes under the bridge of my dad's fiddle. When asked why they were there, he would reply, "So I can say I'll never be broke."
I must have missed the part explaining why you would want to block those passages. I think cold performance would be better with that crossover working the way it was designed.
"RalphG", it sounds like you're one of "those guys" who think the Ford engineers knew what they were doing. I'm one as well.
I don't see why this is necessary except for an all-out race engine. The proper manifolds for those don't have a provision for manifold heat anyway, so why bother?
Blocking the heat riser holes with pennies so far as I know never had anything to do with improving or modifying engine performance.I would think that hot exhaust air would aid in preventing carburetor icing which can be a real problem here. My 52 Merc still has the heat riser valve in the right hand exhaust manifold.
Blocking the heat riser holes with pennies so far as I know never had anything to do with improving or modifying engine performance.
It was a fad that intended to change the exhaust sound that some thought was "cool"
But if you were experiencing 'vapor lock' it may be a step toward reducing the problem.
Period correct pennies sounds just a bit anal
On a more serious note, as cranky as a flat motor is (timing, carb adjustment, fuel distribution and engine temperature) the very last thing I would do is remove the heat under the carb for a "cool sound".