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Acheving max vacuum in a F-350 cab n chassis 400 ci

Old 10-22-2018, 09:27 AM
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Default Acheving max vacuum in a F-350 cab n chassis 400 ci

After just reading that it's all about vacuum, how does one determine the max level in a 400ci for a particular engine?
The vac lines looked real basic and most plugged when I got the truck. I had the 351M rebuilt and changed to a 400 with a cam to help achieve more torque for towing and that it did.
After cleaning the EGR, connecting a vac line and controlling it and dizzy through a temp controlled switch I'm hoping I did the right thing, it seems to run ok and can tell when it opens while idling.
Haven't driven it on highway yet due to finishing up a cab off resto and now it's almost winter.
Your thoughts n comments are more than welcome along with ideas on better MPG if possible... currently 14 max, hopefully the new paint will help come spring lol
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Old 10-23-2018, 10:59 AM
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By tweaking & tuning to increase the vacuum. Buy a MityVac kit that includes a booklet, and read it. I think this is the current version of the one I have:
Amazon Amazon

Or you might be able to just download that manual from their website.

Paint will not help MPG. 14 is pretty good for a big-block V8; my I6 only gets 13.
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