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Turbo Exhaust Flow
scootz - 10/7/15 at 03:20 PM

I ordered a Janspeed exhaust for my Smart Roadster and went with the non-cat option.

It's arrived and I'm a little surprised at the design. The pic below illustrates the cat option (top) and the non-cat option (bottom).

My non-cat exhaust just has an empty chamber where the cat would have gone.

Seems a bit odd to me that they didn't just use a longer silencer or link pipe rather than pipe the gases into a hollow chamber before the silencer!?

Any thoughts?

coyoteboy - 10/7/15 at 03:25 PM

Yep, that's odd and not ideal. Presumably because it's cheaper to make one product and either fit or not fit the honeycomb.

Texan - 10/7/15 at 03:50 PM

Could be good IF it's shaped right. Like an expansion chamber on a 2 cycle engine.

But if it's just a box then probably not good, but maybe not bad.

r1_pete - 10/7/15 at 06:48 PM

Its going to create some turbulence as the gasses enter the chamber, whether you'll notice or not is another matter.

ReMan - 10/7/15 at 07:25 PM

quote:
Originally posted by coyoteboy
Yep, that's odd and not ideal. Presumably because it's cheaper to make one product and either fit or not fit the honeycomb.

Agreed and the reality of there being much -noticeable- difference in performance, unless tuned and rolling roaded is slim

[Edited on 10/7/15 by ReMan]

SPYDER - 10/7/15 at 07:40 PM

The standard R1 5JJ Titanium can has just such a chamber prior to the silencer elements.
So Yamaha think its a good idea.

scootz - 11/7/15 at 05:59 AM

Cheers all.

Volvorsport - 11/7/15 at 04:03 PM

Its just a silencer chamber , but its not good for flow , it wants to be absorption type all the way through , it might be louder aswell like that.....