vectra b straight thru opinions

[cav24v]

Has anyone fitted a race tube (straight through centre exhaust) with the letterbox type irmscher tailbox & if so did it make the exhaust louder/better. The reasons i'm asking is I want a nice sounding exhaust but want to retain the original letterbox type box if possible. I fitted a race tube to my previous vectra with the double d style irmscher box but it made no difference at all to the sound(they must be very well muffled) so I ended up buying a second hand tailbox which is a bit too loud with the race tube. I'm asking peoples opinions so I dont have to spend hours trying different combinations. Thanks for any help.

 

[Matt]

Quite a few people have done this. @Sjdickso has this same setup on his Astra, and sounds very nice with the DD Irmy back box fitted. Fitting a sports cat also makes the sound change quite a bit.

 

[corsaZ22se]

I had a ported Dbilas manifold, custom 2.5" down pipe with 200 cpi cat, remus silenced centre section de restricted and remus twin 3" round back box also derestricted on my Vectra B. sounded good, low down burble, shouted when giving it the beans but cruised nice and sensible. tried straight through centre pipe but was ridiculously loud and gave no power gain over silenced centre section so removed it after 5 days! still got the remus sat in the shed and the race tube.

 

[MikeS]

Got lexmaul 4-1 with sports cat 2.25 downpipe leading to race tube with irmy backbox

race tube gives a boomy feel, they are more suited on the vectra B imo