expansion bellows question

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jefferson
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expansion bellows question

Post by jefferson »

To my knowledge our exhausts have expansion bellows in the crossover and the uppipe. Would it be worth cutting those out and putting in the braided type of flex joint? My reasoning is the smooth interior walls versus the very broken up bellows. It should flow more and I would think make the turbo spool quicker. Does anyone have any experience or opinions on this?

Jeff
91 Black SS 5spd. Edm lights, wrx gauges in dash, 45 degree airbox, cryoed drilled and slotted brakes. Invidia divorced downpipe with custom stainless exhaust. To be installed, aluminum a-arms, manual belts, awic.
93forestpearl
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Post by 93forestpearl »

Flex joints with an inner braid are an EXTREMELY BAD IDEA before the turbo. I've seen more than one let go of the braid, which makes a mess of your turbine wheel.

You are not loosing as much flow from the flex joint. The gas flowing over it creates a boundary layer on the outside, so it's not that big of a deal. The crush bends in the crossover pipe are more of a restriction. In the end, messing with it is really a waste of your time.
→Dan

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Legacy777
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Post by Legacy777 »

There is an inner smooth pipe inside of the metal bellows portion, at least on the up-pipe....and I would assume on the crossover pipe too. So it's not an issue.
Josh

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