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Cut and weld intake manifold??

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Old 11-24-03, 04:25 PM
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Question Cut and weld intake manifold??

i was brainstorming at school today about porting my intake manifold.but i couldnt think of any way i could port the upper intake where it has a 90degree turn then i had a stoke of genius (im sure someone else has done it b4).i was wondering if anyone has anyone cut a cross section of the intake manifold,ported all 4 ports and then welded it back together (and ground down the welds for that stock look).

if no one else has done itb4 i want all ownership of the process.it will be called CPW,for cut,port,and weld.i want ownership over it like that guy did with the supras and BPU J/K LOL
Old 11-24-03, 05:26 PM
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uh how else you think it is ported... except for extrude hone. its a common way of doing it, hell i have seen old school racers do it for years. the tricky part is welding it back together. If the manifold is cast good luck!!
Old 11-25-03, 02:52 PM
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I think I remember that Rotarygod here on the forums has done this; Rotarygod is also in Houston...
Old 11-25-03, 03:02 PM
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Section!
Old 11-25-03, 07:25 PM
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why not just make a custom inlet and tune it to your needs?
Old 11-25-03, 09:53 PM
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why dont u make on and tune it to my needs....j/k

i dont have the engineering background to design my own intake manifold
Old 11-25-03, 10:05 PM
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lol....if u do a search we talked about this in a thread started by me....i also considered cutting and rewelding but supposedly it's a pain in the *** to weld back cast aluminum....iunno why....ur better of extrude honing it
Old 11-26-03, 02:59 AM
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I've cut every different style of RX-7 manifold apart, ported them, and put them back together. It's an awful lot of work.
Old 11-26-03, 04:59 AM
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Originally posted by Mr BiG G
supposedly it's a pain in the *** to weld back cast aluminum....iunno why....

I Know welding cast IRON is a PITA, but I had not heard that about cast aluminium.
Old 11-26-03, 02:34 PM
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go to NW and check out gambone he has a custom intake that willgive any body wood
Old 11-27-03, 07:15 PM
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I'm doing m own inlet when I rebuild my 12a, I've never ported an engine, taken one apart, or done any modifications to one. But I'm very technically minded, read as much as I could - but it's the reading that gives most of the know-how you'll need.

here's the thread on calculating your ideal runner length https://www.rx7club.com/showthread.p...hreadid=199788
enjoy
Old 11-28-03, 04:05 AM
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Much of that thread was a big debate and it turned out that both of us were arguing about 2 entirely different but related intake phenomena. That formula is a shortcut to avoid a few other steps. It still gets extremely close.
Old 11-28-03, 05:08 PM
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well, after the first page, i just stopped reading anyway (i got what i needed!)
Old 11-29-03, 03:48 PM
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cast aluminum is very easy to weld, it's catching the micro holes that's a PITA, I use a harmonic table to weld it and I've never had a micro leak..
Old 11-29-03, 05:44 PM
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Right then - I've only just realised something.

When you do that equation, do you make the measurement for the final length, from the exterior of the block - or from the port itself?

Oh yeah, and where do you measure the angles for the ports from? I'm making a PP, so I cant use any standard measurements
Old 11-29-03, 09:42 PM
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Re: Cut and weld intake manifold??

Originally posted by T04Eneedy
i was brainstorming at school today about porting my intake manifold.but i couldnt think of any way i could port the upper intake where it has a 90degree turn then i had a stoke of genius (im sure someone else has done it b4).i was wondering if anyone has anyone cut a cross section of the intake manifold,ported all 4 ports and then welded it back together (and ground down the welds for that stock look).

if no one else has done itb4 i want all ownership of the process.it will be called CPW,for cut,port,and weld.i want ownership over it like that guy did with the supras and BPU J/K LOL
Nice try, though!

You can see the weld at the start of the runners.


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