All,

Sorry if this sounds 'dumb', but does the position of the CAT really affect exhaust flow?

Is it better in the dump pipe (like factory position), or further down the system, like in the mid section.

Would be interesting to know.

cheers

It will be more effective in the factory position, gets hotter quicker. if its one of those hi-flow cats it will have little effect on flow in the downpipe. As long as its towards the bottom of the pipe. Factory position also lessen the chance of it getting crunched by a speed bump.

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F.B. Racing
01 WRX (STI badged)
2010 XR5 Focus
06 Impreza Hatch 2.0i

The dump pipe spot will overheat it in your application Gav......big difference in exhaust flow in that location on a stock car V a 380+hp at the crank set up.

It also means that you won't be able to run a wide band in the preferred cooler post dump - before cat - location, should you want or need to run the vipec with wideband feed back active.

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^^Good point, Wayne make sure you read this!!

That's why I suggested the centre pipe position like my Butler one.

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221.7KW-ATW 498.5NM MMS ROLLER DYNO & BUILT BY STi NINJAS, BUILD #318/600

EBISU SUBARU, SHIBUYA-KU TOKYO

but who is 'bulter'?

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[CENTER][COLOR=#ff0000]Built Ej207: Semi-closed RA Cases - Wiseco Forgies - Manley rods - BC 272 cams - GDA Heads - billet f/whl - Vi-pec - WbO2 - 800cc Yellow tops - TD05-20G - 409Hp ath @ 1.75bar on E85[/COLOR][/CENTER]

A cranky old fart

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By cat you mean "gutted piece of metal" yeah?

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WHS.

Brent.

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