Downpipes
 

has anyone ever heard or seen anything about expansion chamber downpipes for turboed vehicles.

yup, with the correct chamber volume you can totally de-restrict the turbo and not need to run big bore exhaust, so you can keep noise down to meet strict tack noise limits. the idea is to open out very quickly from the turbo into the chamber then taper into a smaller bore after about 10 inches. been a while but i did see some scetched drawn up my a race engineer

oh rite. I was wondering if such a thing existed or if my theory that one would be good had some fatal flaw Something A bit like the expansion chambers you see on 2 stroke motorbike exhausts was an idea( your description is what i was thinking). Good to see its been done before though. Thanks