Intake manifold rough inside???
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Instructor
Joined: Jan 2000
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From: Bryant Ar
Intake manifold rough inside???
I was surprised when I pulled my carb off my 1981 to find the inside of the stock aluminum intake very rough. Almost a pitted look and feel. Is that normal??? Seems like it would cause some resistance in air flow.
Vetjet
Vetjet
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yes, that's the as cast finish. There's next to no resistance in flow because the rough surface holds a small film of air, a boundary layer and air on air has less resistance than air on steel, no need for a finer finish than 80 grit. It's a complete waste of time to polish the inside, the rough will also help keep the fuel atomized.
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From: Exiled to Richmond, VA - Finally sold my house in Murfreesboro, TN ?? Corner of "Bumf*&k and 'You've got a purdy mouth'."
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St. Jude Donor '06-'10, '13
what he said -- don't polish it.
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From: Smalltownville Michigan
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St. Jude Donor '09
TT is right. If you polish it, you will mess up the characteristics and cause a puddling issue.. the roughness aids in better fuel atomization. Now on the exhaust side, make that as glassy as you can!
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From: Hoosier
Cruise-In III Veteran
Originally Posted by Aflac
TT is right. If you polish it, you will mess up the characteristics and cause a puddling issue.. the roughness aids in better fuel atomization. Now on the exhaust side, make that as glassy as you can!
