Would someone please explain the purpose and function on the economizer valve that is in the bottom of the fuel bowl. Must of looked at a bunch of them over the years cleaning carburetors and never made much sense as to why they are even there.
Generally called the power valve. Something kinda like this: vacuum keeps it closed, tromp the pedal it comes open for more fuel.
as said above, - also gives more fuel for under load going up hills etc….. Block it off if you want - ( I wouldn’t recommend to though) and see/ feel the difference. I tried running my tri-carb fixed linkage without PV’s and I could notice the difference.
It adds more fuel to your mixture when your vacuum drops. Its closed at idle and opens at a preset vacuum amount. So when you are cruising along its most likely closed then when you accelerate it will open. The more air going in needs more fuel.
A couple more points for you if interested. - When I put mine in, I sit it in place with fuel in the bowl above, and let it sit overnight to ensure that it doesn’t leak. - If you have a backfire through the carb, it supposedly (from what I have read on here) will blow the diaphragm in the power valve and it will need to be replaced. - power valves can have different ratings, standard is 7.5 for single carb flathead- and later power valves don’t always fit correctly. lots more info here……although some links may no longer work. https://www.jalopyjournal.com/forum/threads/links-to-holley-94-technical-info.286574/
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