Removing decat off vectra

**Gt-Coupe** · 9th May 2010, 23:44

i'm getting twin pipes on my vectra this week and i'm wondering if i decat it will it give me any more power and will it be much noisier?

**shadyone** · 10th May 2010, 09:37

Really shouldnt make much difference noise wise and you may pick up a fraction more power, is it worth the hassle come mot time though.

**Hyperhart** · 10th May 2010, 21:10

Just a couple of things, firstly i had the cat removed from my GSi last week and to be honest in my eyes i seem to have lost a bit of power, secondly come MOT time it could become a pain in keep having to replace the cat unless you have pre cats (the GSi has 2 pre cats so the main cat can be removed and will still be fine for the MOT). Thirdly it might just be me again but removing the cat seems to have altered the way the car sounds, full stainless system was fitted the same time as my decat and sounds a bit odd to me.

**ditchp** · 10th May 2010, 21:13

de-cat on a diesel is fine mate, not needed on them for MOT as a soot test is all that is done...

not sure on the power gain's but deffo a free flowing system and a great noise from the turbo spooling when changing gear

HTH

**Hyperhart** · 10th May 2010, 22:00

Originally Posted by ditchp

de-cat on a diesel is fine mate

HTH

Sorry, didn't realize it was on a diesel.

**OPC** · 10th May 2010, 22:20

Originally Posted by ditchp

de-cat on a diesel is fine mate, not needed on them for MOT as a soot test is all that is done...

not sure on the power gain's but deffo a free flowing system and a great noise from the turbo spooling when changing gear

HTH

All that expensive for nothing then

**ditchp** · 10th May 2010, 23:49

i have always been led to believe that you will gain about 10 - 15 % extra from a free flowing sport's exhaust - air filter combination, if you want more bigger gain's then a re-map afterward's will be a good idea and what with the added air intake - exhaust gas flow the re-map will hopefully produce a little more power than it normaly would.

and it's only money in the end and you can't take it with you....lol

**Gt-Coupe** · 11th May 2010, 00:05

ye i'm getting her remapped to 200bhp in few weeks so i was gonna decat it before then! ye mot on a diesel with out a cat is fine they pass no problem!