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Wrenchbender Ret · 04-20-2009, 05:43 PM

.375 is 3/8 in. It could be a little low depends on the carb. You need to take the number off the carb & match it to the speck sheet. You are probably hooking your vacuum gauge to ported vacuum. It will be lower then full manifold vacuum. The port on the manifold is the actual vacuum.

04-20-2009, 05:43 PM	#15
Wrenchbender Ret Registered User Join Date: Oct 2005 Location: Overland Park, Ks. Posts: 5,229	Re: Qjet accelerator pump .375 is 3/8 in. It could be a little low depends on the carb. You need to take the number off the carb & match it to the speck sheet. You are probably hooking your vacuum gauge to ported vacuum. It will be lower then full manifold vacuum. The port on the manifold is the actual vacuum.