Back pressure....

[DazVR6]

Have a 6 branch manifold, deact and a 2 box exhaust on my vr but not very loud, infact id say its standard sounding....thinking of removing the middle suitecase silencer which will make it louder but what affect if any will there be on my car..? will the lack of back pressure cause a big loss in performance...?

Have asked on Vr6oc and no-one seems to know, anyone here have a veiw or any ideas...?

[boneybradley]

removing this box wont really effect your power output but from experience it will alter the rev range... you'll proberbly find it feels/is faster higher in the rev's... but less lower down.
this was my experience when i fitted a pipe instead of the middle box on mine. and if that did increase power I would say it was minimal but more driveable in mid range

[Kenny_1.6]

well, last night my flexi-pipe gave up and basically got left with the exhaust gases going from engine block, manifold, downpipe, air.  and as boney said, only noticed a slight loss in power at lower revs, but top end seems quicker if anything (and deafingly loud!!), and thats with NO backpressure, so i doubt you'll lose much at all (bare in mind, i do have a 1.6 8v, so VR6 might be slightly different

[DazVR6]

I don't mind a slight lose of power but don't want it to be as flat as a pancake type of lose....hmmmm anyone else care to comment..?

[russ-vdub]

i've always thought about this and lots of people have different opinions. i have a ever increasing hole in one of my down pipes and i from what i can tell it has lost a fair bit of low torque like mentioned. i wouldnt worry too much about losing bp from a mid box, rallye cars dont have them and they have no problems