CorradoVR6-Turbo 0 Posted April 30, 2003 Hello all Thinking of de-cating my vr6 to improve the flow . But does it make any difference>? :? Has anydody done it ? Made it quicker? Any help Cheers James :lol: Quote Share this post Link to post Share on other sites
G60 0 Posted April 30, 2003 this has been beated to death on almost all the forums and lists... but i don't think i've seen it on this one yet. try looking in vortex, and yahoo lists.. it makes it a bit doggy off the line, gives it a bit more quickness at higher rpm. in a torquey G60 its a good idea to lose is usually.. not sure if you VR6 guys would benefit too much.. Quote Share this post Link to post Share on other sites
LowG 0 Posted April 30, 2003 this has been beated to death on almost all the forums and lists... but i don't think i've seen it on this one yet. try looking in vortex, and yahoo lists.. it makes it a bit doggy off the line, gives it a bit more quickness at higher rpm. in a torquey G60 its a good idea to lose is usually.. not sure if you VR6 guys would benefit too much.. on a g60 you need the cat,when you take it out you will lose loads of back pressure which will lower the tourqe on low rpm,you just replace it with a race cat. On a turbo is best not to have any back pressure at all. Quote Share this post Link to post Share on other sites
Chris VR6nos 0 Posted April 30, 2003 Hi fruit bats! James the VR comes as std with a performance cat, however the benefit you will see is because you use Nitrous, this will produce the same CFM of exhaust gas at mid revs that full revs would produce so when you are getting up to high revs, well you see where I'm coming from don't you? Well yes, it is accepted that removing it will benefit. By the way I sold an aquaintance of yours a Wizard of Nos kit from the shop today! He has a black Citreon Saxo and he asked if you would fit it for him remember? I went through it all and showed him what's what. ;-) Chris VR6 Quote Share this post Link to post Share on other sites
Dubcharged 0 Posted April 30, 2003 this has been beated to death on almost all the forums and lists... but i don't think i've seen it on this one yet. try looking in vortex, and yahoo lists.. it makes it a bit doggy off the line, gives it a bit more quickness at higher rpm. in a torquey G60 its a good idea to lose is usually.. not sure if you VR6 guys would benefit too much.. on a g60 you need the cat,when you take it out you will lose loads of back pressure which will lower the tourqe on low rpm,you just replace it with a race cat. On a turbo is best not to have any back pressure at all. If you drive your G60 under 4k rpm all the time then this would be true. However, if you drive it like me up to 6k (i go to 6300) then the cat restricts flow. I'm using a 2 1/2" bore exhaust straight through, yes i have lost some torque bottom down, but the gain in mid and top is what i'm after. :D Quote Share this post Link to post Share on other sites
LowG 0 Posted April 30, 2003 but than again cant you put a cam for that sort of powerband,i have custom exhaust system decated waas when i bought the car,sounds nice though :D plus i get loads of back flames everytime 8) Quote Share this post Link to post Share on other sites
baz 0 Posted April 30, 2003 the louder the exhaust backbox = the more back presure, is this true? Quote Share this post Link to post Share on other sites
Joe M 0 Posted April 30, 2003 the louder the exhaust backbox = the more back presure, is this true? doubt it, if you take the backbox off it gets even louder but there will be less backpressure Quote Share this post Link to post Share on other sites
Dubcharged 0 Posted May 1, 2003 Lowg: Yes, cam helps mid and top by increasing duration, but this needs to be complimented by a free flowing exhaust, no point increasing intake and exhaust valve duration if you're gonna restrict the exhaust gases where the cam comes in, (mid, top). Quote Share this post Link to post Share on other sites
G60 0 Posted May 1, 2003 lowg: my (sick) G60 is only putting out 12psi (its cammed)... and it has heaps of torque to spare with no cat. flames are bad ass! :twisted: :lol: Quote Share this post Link to post Share on other sites
julesz 0 Posted May 1, 2003 Mine is a August '92. Guess i need to keep the Cat. Flames sound cool though :twisted: :shock: :lol: Quote Share this post Link to post Share on other sites
GazzaG60 0 Posted May 1, 2003 i run a std G60 without cat. 2.5 straight thru. up to 3k there is a loss i think Quote Share this post Link to post Share on other sites
DORSET_V_DUBSTER 0 Posted May 1, 2003 Chris VR6nos, Sorry to hijack the thread, but could you give me/us some more info on NOSing. Whats involved and at what sort of price. Thanks matey ! Scotty :D Quote Share this post Link to post Share on other sites
CorradoVR6-Turbo 0 Posted May 2, 2003 Hi fruit bats! James the VR comes as std with a performance cat, however the benefit you will see is because you use Nitrous, this will produce the same CFM of exhaust gas at mid revs that full revs would produce so when you are getting up to high revs, well you see where I'm coming from don't you? Well yes, it is accepted that removing it will benefit. By the way I sold an aquaintance of yours a Wizard of Nos kit from the shop today! He has a black Citreon Saxo and he asked if you would fit it for him remember? I went through it all and showed him what's what. ;-) Chris VR6 Cheers Chris think i will de-cat just to c what ill gain and all well ill c u tomorrow to help with box :D Yes the lad you sold wizard kit to got back in touch with Trev to resolve problem P.S LowG ......what a sweet ass !!!!!!! :shock: Quote Share this post Link to post Share on other sites
ipk 0 Posted May 4, 2003 whats the cut of for having to legally have a cat fitted? i thought it was 1st jan 93, but julesz is running an aug 92 car and says he needs one (mines dec 92). what kinda trouble am i gonna be in for running a de-cat car? Quote Share this post Link to post Share on other sites
Joe M 0 Posted May 4, 2003 You need a cat from K plate onwards, Aug '92. Not sure about roadside emmisions tests but it will be an mot failure without. Quote Share this post Link to post Share on other sites
Banana Man 0 Posted May 5, 2003 The legislation for the new emmisions test didn't come in till Jan 1st '93 but it is stated that you have to have a cat fitted from Aug 1st '92 which makes alot of sense :? makes no difference to me though coz i ve got a '91 and have already decatted it :D didn't really notice any difference either way apart from the new louder exhaust note but I had a complete powerflow system done at the same time and I said I wanted it loud :D Quote Share this post Link to post Share on other sites
VR6 0 Posted May 5, 2003 Ant, I'm pretty sure that no law states that you have to have a cat fitted. You do have to pass the emissions test though. Without a cat, this could prove a lot harder! /waits to be proved wrong. Quote Share this post Link to post Share on other sites
Banana Man 0 Posted May 5, 2003 Try impossible Tom :D a car without a cat is is allowed a maximum of co3.5% hc a car fitted with a cat is allowed a maximum of co +-.05%hc if I remember correctly and that is impossible to achieve without having a catylyst installed in my opinion correct me if I'm wrong tho somebody thats just from what I ve read about the MOT test Quote Share this post Link to post Share on other sites