adam_christie 0 Posted April 7, 2007 Report Share Posted April 7, 2007 Hi!Just had an exhaust custom made and fitted, and I asked for a 2.5" system to be installed as opposed to a 2.25" as I'm planning on going turbo, however the noise from the exhaust is now pretty deafening, and until I get the turbo on it's going to be pretty unbearable to drive to be honest, so I was toying with the idea of installing a butterfly valve just before the backbox, a bit like this one from Oz: http://autospeed.drive.com.au/cms/A_2291/article.html Just wondering if anyone's done this or has any useful info about it?Hi performance cars like Lamborghini Diablo and Ferrari use them, and they're pretty popular with ricers, but I've yet to see one on a VW.......Cheers!Adam Link to post Share on other sites
matth76 1 Posted April 9, 2007 Report Share Posted April 9, 2007 The R32 has one. Easy to remove (apparently) but not sure how easy to install. Link to post Share on other sites
VR6Rob 0 Posted April 9, 2007 Report Share Posted April 9, 2007 The R32 exaust valve works by bypassing the rear box Have you got a middle box? if not you could get one fitted and a bypass pipe with the valve. Link to post Share on other sites
adam_christie 0 Posted April 10, 2007 Author Report Share Posted April 10, 2007 Yeah I've got a middle box, so in theory it should be quiet enough anyway? Been to speak to the owner of MIJ Exhausts in Walsall and he's aggreed to swap the middle box for a 2.25" one FOC. He's adement that this will quieten it down and that I should still have no problem installing a turbo. He even claims that I should see some improved torque lower down the rev range. I'll keep you posted. Link to post Share on other sites
IbiVR 0 Posted April 10, 2007 Report Share Posted April 10, 2007 2.25 will be ok for turbo unless your going for big power. You should get 10psi easily enough with that. Enough for say 300-330hp. You'd probably get more, but all depends what turbo is used.When you put the turbo on though go for a 3" downpipe and step it down near the first box/cat.Tom. Link to post Share on other sites
adam_christie 0 Posted April 10, 2007 Author Report Share Posted April 10, 2007 Ah ok, it sounds like it could be ok then......MIJ's High Flow CAT's are 3" as standard I think. Would it be an option of going for something that size and then have it step down to 2.25" where the middle box is? Or should I go for a smaller cat? Link to post Share on other sites
IbiVR 0 Posted April 10, 2007 Report Share Posted April 10, 2007 Keep it 3" for as long as you can after the turbo, so use the 3" cat and then step down. That should be fine for a reasonable power level.Tom. Link to post Share on other sites
adam_christie 0 Posted April 10, 2007 Author Report Share Posted April 10, 2007 Cool.Now then, need to start building up my turbo parts list! Know any good manifold suppliers? Link to post Share on other sites
matth76 1 Posted April 10, 2007 Report Share Posted April 10, 2007 Speak to The Phirm. They have recently turboed their show vr - I believe they sourced EIP parts but they will answer all your questions and best places / prices of parts etc. The main issue is the manifold with the vr being rhd. Link to post Share on other sites
xyber 1 Posted May 20, 2007 Report Share Posted May 20, 2007 instead of bypassing the rear box, could you do it to bypass the cat? could be interesting Link to post Share on other sites
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