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Old 08-09-2010, 01:25 PM   #1
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Default Ext. Wastegate on BEGi Manifold

Instead of having them weld a flange to the cast mani, can I just machine the bottom flat, and drill/tap it for the wastegate, so the wastegate sits directly against the manifold? I'm sure there's something wrong with this idea, so please enlighten me.

I don't like the idea of welding cast.

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Old 08-09-2010, 01:27 PM   #2
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Its pretty thick in that area, I don't see why not. Might not get enough exhaust flow/pressure in the manifold to force enough gasses through it though.
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Old 08-09-2010, 04:38 PM   #3
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It's not thick enough, sorry.... You could weld on a flange as long as the WG would not hit the manifold. Welding the cast manifold is not a problem - as long as it is done correctly!!
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Old 08-09-2010, 06:48 PM   #4
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Welding cast is just fine. If you can source a older FM/Begi manifold you can drill and tap those.

Take a look at PatsMX5 manifold build: ZING! Welded properly and it will be just fine.

Also if you are looking to maybe switch your manifold, there is the HKS. Check out Gianic: ZING!


Older Begi/FM manifolds had thick areas that you could drill and tap: My FM3 is beefy as hell and works like a charm.

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Old 08-09-2010, 07:01 PM   #5
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seen it done on a HKS mani too.
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Old 08-09-2010, 09:07 PM   #6
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that manifold looks like it was designed to flow!

just build a tubular manifold... if your serious enough to get an external gate spent the $ to get a real manifold.
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Old 08-09-2010, 11:13 PM   #7
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Quote:
Originally Posted by shlammed View Post
that manifold looks like it was designed to flow!

just build a tubular manifold... if your serious enough to get an external gate spent the $ to get a real manifold.
Hey hey, no need to bash my antique Shiiit, I am the fourth or fifth owner of that fine beauty. Probably over 200K on that thing and I still make full boost before you start building Just messing man, that picture was taken before I cleaned it, painted it and ported the whole thing with a dremel. It does look ugly as hell though, lol.

If the OP already has the manifold then there is no need to spend alot of cash on a new manifold and downpipe. It will be be cheaper and easier to just modify the one you already have. Plus the benefit of having a cast manifold on a daily driver. These things are built like tanks and will probably outlive the car.
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Old 08-10-2010, 01:57 AM   #8
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just chirpin.

but a quality manifold will last just as long as a cast manifold.
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