1.8L VS 2.0L T4 exhaust systems Options

[technicalninja]

I've wondered why Porsche built different exhaust systems for the T4.

It appears that any year complete exhaust system can be installed on any year T4.

And yet the systems are so different that even the mount at the transmission needs to match the exhaust.

Why?

It seems the systems have the same size pipes.

The 1.8/1.7 have a short "S" kick up at the back that doesn't look like it will affect flow very much.

What am I missing?

Are the 2.0L mufflers higher flow?

Was it just a sound difference?

I didn't "see" an obvious flow difference when I bought a pair of used 1.8L SSI exchangers and the Bursh muffler that fit them.

Was I wrong?

[technicalninja]

1974 1.8 stock heat exchangers have the same tube size as 2.0.
@mb911 might have flow info on stock mufflers

Sorry long gone information

@bdstone914 now has a flow bench. (IMG:style_emoticons/default/smilie_pokal.gif) We’ll make it Bruce’s job to set up fixtures and measure flow for all the OEM mufflers as well as Triad, Bursch, Monza, etc. Probably has nothing better to do with his time.

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NO, just flat freaking NO!
(IMG:style_emoticons/default/chair.gif) (IMG:style_emoticons/default/chair.gif) (IMG:style_emoticons/default/chair.gif) (IMG:style_emoticons/default/chair.gif) (IMG:style_emoticons/default/chair.gif)

If Bruce has extra time on his flow bench, I can think of HUNDREDS of things I'd test before I jacked around with stock 914 exhaust...

BAD Superhawk!
BAD, BAD, BAD!
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