I have 2 Professional Products Hurricane single plane manifolds. The floors have been filled in on these intakes. I drew over 1 ports to show the reference of where gasket would go and how much floor is filled. I have run these since 2012 and now going EFI so no longer needed. $200 ea + shipping
I also have a Weiand Stealth dual plane with the floors also welded up. $175
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Professional Products Big Block Chevy Hurricane Satin Intake Manifold (53031)
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Sunday TTT

What is the issue or advantage of having them "welded up"?

My heads are custom ported and have the floors of the intakes welded up. This decreases the intake volume, but ported to flow as much or more air than larger intakes volumes. This increase port velocity in turn increases HP and TQ. This is kinda like the old school round intake on rectangle port heads to add performance, but a perfect matching combination. I can grind out the weld to match a rectangle head, but my head guy said it would be a minor benefit to someone with conventional rectangle port heads. And to grind it out if they want it removed. If you look at the pic you can see that my intake ports have the raised floors and look more square.
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Is that a Weiand 8019? It looks like it, but hard to tell in the pic. Would it work for stock oval port heads on an l29?

Thanks for the lesson on the intakes ! PM me I would like to find out if this would be beneficial for my application.

Yes, it is the older style 8019. I have no idea if it would work on an L29 head. It might be too tall. I don't know if it would seal.
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