Should a broken dash pot be replaced?

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It is my understanding that the dashpot on the 1966 automatic Wildcat (located on the carburetor, driver side) is just for emission control — to prevent large CO emission when the engine decelerates too fast (the dash post slows the deceleration).

The dashpot on my Wildcat is broken and the engine runs just fine. So wondering whether it is worth it to replace this piece?

Are there others with broken dash pots?
 
When you close the throttle suddenly, the mixture can go rich, and that can cause stalling. Probably says that in the Chassis Manual.
 
Could be also why it's not stalling is the idle speed is above idle specs. Does the vehicle SOMETIMES, after it is completely warmed up & hot after a 20-30 minute run at highway speeds, have a tendency to not want to shut done completely??? & run on??? IF no you don't need it as Larry
has stated.

Tom T.
 
It is my understanding that the dashpot on the 1966 automatic Wildcat (located on the carburetor, driver side) is just for emission control — to prevent large CO emission when the engine decelerates too fast (the dash post slows the deceleration).

The dashpot on my Wildcat is broken and the engine runs just fine. So wondering whether it is worth it to replace this piece?

Are there others with broken dash pots?
These are referred to as an "anti stall dashpot"
It is my understanding that the dashpot on the 1966 automatic Wildcat (located on the carburetor, driver side) is just for emission control — to prevent large CO emission when the engine decelerates too fast (the dash post slows the deceleration).

The dashpot on my Wildcat is broken and the engine runs just fine. So wondering whether it is worth it to replace this piece?

Are there others with broken dash pots?
These are referred to as anti stall dash pots. They stop the throttle closing abruptly while engine revs are higher than a fast idle. High engine revs under a closed throttle creates a strong vacuum that sucks excessive fuel in through the idle circuit of the carburetor. This excessively rich mixture can cause a few seconds of rough idling or even a stall.
The anti stall dash pot allows a little air to flow around the throttle plate for about half a second while the revs settle down thus preventing the hard suction on the idle jet.
 
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These are referred to as an "anti stall dashpot"

These are referred to as anti stall dash pots. They stop the throttle closing abruptly while engine revs are higher than a fast idle. High engine revs under a closed throttle creates a strong vacuum that sucks excessive fuel in through the idle circuit of the carburetor. This excessively rich mixture can cause a few seconds of rough idling or even a stall.
The anti stall dash pot allows a little air to flow around the throttle plate for about half a second while the revs settle down this preventing the hard suction on the idle jet.

Thank you for the technical explanation.
Could be also why it's not stalling is the idle speed is above idle specs. Does the vehicle SOMETIMES, after it is completely warmed up & hot after a 20-30 minute run at highway speeds, have a tendency to not want to shut done completely??? & run on??? IF no you don't need it as Larry
has stated.

Tom T.
I have no issue with shut down. But it does need a tune up and may have an idle speed above specs. When I have solved the air cleaner issue (i.e. how to get over 135 cfm of cool air in a Wildcat carburetor despite low clearance and no cowl induction, without making holes in the lid?), I'll get it tuned up and then we'll see if it stalls.
 
Thank you for the technical explanation.

I have no issue with shut down. But it does need a tune up and may have an idle speed above specs. When I have solved the air cleaner issue (i.e. how to get over 135 cfm of cool air in a Wildcat carburetor despite low clearance and no cowl induction, without making holes in the lid?), I'll get it tuned up and then we'll see if it stalls.
Is 135cfm a typo? To calculate air flow multiply cubic inch capacity of the engine x revs at peak power and divide by 3456.
350 x 5800 ÷ 3456 = 587cfm.
Adjust for volumetric efficiency (80% is a good rule of thumb number for a stock engine) and that will give you a fairly good cfm number to help choose your carburetor size. High performance heads and big cams will increase volumetric efficiency at higher rpm .
 
Is 135cfm a typo? To calculate air flow multiply cubic inch capacity of the engine x revs at peak power and divide by 3456.
350 x 5800 ÷ 3456 = 587cfm.
Adjust for volumetric efficiency (80% is a good rule of thumb number for a stock engine) and that will give you a fairly good cfm number to help choose your carburetor size. High performance heads and big cams will increase volumetric efficiency at higher rpm .
Fantastic... that is exactly what I am struggling with. The tiny air filter recommended by Wix for the Wildcat (No. 42084 - 2.36" height, 12" diameter) is only rated to 135 cfm, which I suspected was way too low. But clearance is non-existing, and in addition to limited CFM you don't want to suck the hot air that accumulates under the hood on back of the engine.

One solution is to go with a 14" K&N XStream Air Flow Assembly (66-3040) with a E-1650 3" filter and a 66-1401 air flow top -- stability of air flow coming direct from top instead of sides (less turbulence) is apparently as important as volume -- but instead of using the K&N base (1 1/4 drop) use a Speedmaster PCE101.1005 dropped base (1.5" drop) that gives you an additional 1/4" clearance.

In the alternative to the PCE dropped base, I would use an induction pan but turned towards the front to prevent the air cleaner from sucking the hot air from the back of the engine compartment. Something like: (1) Five Star Cowl Induction Cold Air System https://pitstopusa.com/i-5069534-fi...ass-for-a-14-element.html?ref=category:132346 (and add an insulation/weatherstrip band to get a seal with the hood) or (2) the Allstar Performance Lightweight Aluminum Air Pan https://pitstopusa.com/i-5066263-allstar-performance-lightweight-aluminum-air-pan.html (but I would basically cut the the flat panel and keep the round back).

And/or make a couple of holes in the hood and add hood vents: https://cheesebilt.com/products/universal-mount-ventsScreenshot-20190306-203226-Gallery_1024x1024@2x.jpg
 
you'll have to do it off center or it won't break through the piston attached to the plunger in the middle. Doesn't matter otherwise, just needs a small hole. Basically you are creating a sealed cylinder that only allows movement as quickly as the fluid viscosity allows it to go through the diameter of the hole. Small hole = slower OR more viscous liquid = slower.
 
When you close the throttle suddenly, the mixture can go rich, and that can cause stalling. Probably says that in the Chassis Manual
I didnt see it in my manual, but I get stalling from this happening even though the vehicle is tuned with four gas analyzer, vacuum, and timing. I'm probably going to put back in the dashpot. I have automatic too.
 
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