hi everyone im going stage two but been told i need a sports car an high flow downpipe. would a decat not work as good or do i defo need the high flow downpipe,what you guys running an what sort of gains have you got.thanks
hi flow downpipe or decat
- Thread starter paul-murphys
- Start date
Hello, this was recently asked in this section.
I opted for the 100 cell high flow sports cat as it is the most free flowing cat you can get,and you will still pass MOT emission tests. i would personally recommend that over a decat as you would end up either failing the MOT,or having to constantly switch the cats before each MOT.
and either way you go,a bigger downpipe IS recommended, 3" i beleive. this is because the standard downpipe would create a bottleneck and it gets restrictive, so i would factor in a few extra bob to get that done on top of the cat.
you do get a bit of a gain from it,around 5-10 bhp odd, but remapped to suit it,it will make a good difference as well as a deeper sound.
I opted for the 100 cell high flow sports cat as it is the most free flowing cat you can get,and you will still pass MOT emission tests. i would personally recommend that over a decat as you would end up either failing the MOT,or having to constantly switch the cats before each MOT.
and either way you go,a bigger downpipe IS recommended, 3" i beleive. this is because the standard downpipe would create a bottleneck and it gets restrictive, so i would factor in a few extra bob to get that done on top of the cat.
you do get a bit of a gain from it,around 5-10 bhp odd, but remapped to suit it,it will make a good difference as well as a deeper sound.
but i would have though a decat would give no restriction. an only have mot once a yr so wouldn't mind having to change it so little. How much you pay for your sport cat an downpipe?
the decat would remove the restriction of the twin cat it replaces, however the standard downpipe is still a restriction on its own due to its awkward spiral shape (i think) or something. so thats what i did
cost me £120 including fitting for the sports cat (and trading in my old one), and £150 including fitting for a custom downpipe.
to be brutally honest,i felt no improvement with the sports cat,only a (slightly) deeper rumble mid revs,
but changing the downpipe made a hell of a difference even before the map! the turbo spooled up faster,and it sounded a lot nicer,i could hear the turbo spooling up more.loved it and still do.
Hi,
I have had a custom 3" downpipe and decat fitted on Thursday and i can tell the difference, i havent had my stage 2 map yet but already as Faisal said the turbo spools up faster,and it sounds awesome. I havent had it RR yet so not sure of the BHP increase but maybe 5 - 10. Its well worth doing!
I have had a custom 3" downpipe and decat fitted on Thursday and i can tell the difference, i havent had my stage 2 map yet but already as Faisal said the turbo spools up faster,and it sounds awesome. I havent had it RR yet so not sure of the BHP increase but maybe 5 - 10. Its well worth doing!
parksy
Guest
where you get your downpipes from? I want new downpipe. Will probe sell my decat an trade in cat an buy sports one. Anyone got links where got theres from. Thankyou
I had my downpipe and system made by a local exhaust fabricator in Nottingham (not powerflow) i had seen some of his work previously so went and had a chat with him about the options ie: sports can or decat and decided to go decat.
i would say get a 200cell cat.
nats c()ck of a difference in power conpared to the 100 cell and will avoid potential futures issues.
If you de-cat it, you wont pass an MOT and you may end up putting in a silencer in its place. (unless you are deaf).
Also the downpipe will then compromise any gains.
then... you appear to be looking at a hybrid... so then it makes more sense to get downpipe and 200 cell cat. IMO.
Not cheap though.
nats c()ck of a difference in power conpared to the 100 cell and will avoid potential futures issues.
If you de-cat it, you wont pass an MOT and you may end up putting in a silencer in its place. (unless you are deaf).
Also the downpipe will then compromise any gains.
then... you appear to be looking at a hybrid... so then it makes more sense to get downpipe and 200 cell cat. IMO.
Not cheap though.
how much you pay for it mate, i want a 3" made as well but dont want to pay silly money.
Decat is NO good! I have tryed and tested it. I brought a full blueflame system with downpipe, decat and cat back. The car sounded good with the cat back, with the decat it was too loud and droning sound even at low revs, the sort of sound that would annoy you on the motorway.
It defiantly lost power when i put the decat on, it held back in third and could feel it struggling.
Instead of buying the sports cat which are around 400-500 £ i brought a 200 cell sports cat from hoffman sports cats, i choped the lenght out of the straight decat and got the sports cat welded straight in. which cost me £ 105 for cat , its no different in my opinion to any other sports cat system only it cost hundreds less. It has more power now than the decat and more than the standard cat, i would have thought it would have been better with the decat but somebody told me it probably needs some back pressure and the k04 being a smallish turbo wouldnt be able to run as good with a decat, how a big turbo would. it is defiantly better withe sports cat and the noise has quietened right down to near standard, just a better spool up noise and turbo noise through the exhaust.
It defiantly lost power when i put the decat on, it held back in third and could feel it struggling.
Instead of buying the sports cat which are around 400-500 £ i brought a 200 cell sports cat from hoffman sports cats, i choped the lenght out of the straight decat and got the sports cat welded straight in. which cost me £ 105 for cat , its no different in my opinion to any other sports cat system only it cost hundreds less. It has more power now than the decat and more than the standard cat, i would have thought it would have been better with the decat but somebody told me it probably needs some back pressure and the k04 being a smallish turbo wouldnt be able to run as good with a decat, how a big turbo would. it is defiantly better withe sports cat and the noise has quietened right down to near standard, just a better spool up noise and turbo noise through the exhaust.
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i disagree though. having decat + dp fitted after havin cat back i felt the car was more responsive and pulls hard all the way through the revs.
had custom map now and its even better.
had custom map now and its even better.
plus at full throttle i say louder the better
it its not too loud on motorway up to about 85mph then it suddenly gets a lot louder at 90mph.
it its not too loud on motorway up to about 85mph then it suddenly gets a lot louder at 90mph.
what downpipe did you have, my decats got 2 inputs so would fit
straight on standard dp. what decat you got? im in 2 minds what to do.
how much you pay for your custom bulit exhausts?
straight on standard dp. what decat you got? im in 2 minds what to do.
how much you pay for your custom bulit exhausts?
i got blueflame dp and decat all one pipe through. If you only got decat to fit then fit it and see wot its like and decide on dp after.
dont mind me asking how much you pay? i was thinking custom like what jwfmic did just need to find place that will do it, im confused lol dont no what to do
heres my fabricated decat with sports cat, works great, 200 cpsi cat and the decat pipe. sounds alot quieter than the decat, just a bit louder than standard but with alot better turbo spool up noise
easy to make and costs less than 200 if you pick up the decat cheap enough.
easy to make and costs less than 200 if you pick up the decat cheap enough.
that looks really good. have you got complete system? think might have to see how runs with decat then if bad get system made up or do what you have done. did you make it yourself? i got a friend that can weld so thats ok.
i cut the lenght out of the decat pipe with a metal hand saw. fitted the sports cat in place and got it tacked in place, you just need to line it up and make sure its straight, the correct length, and the flanges at the end are in line still.
on the exhaust itself there is a line of it looks like plasma weld where the tube has been made, i just used this to line it up with. tryed it up against the exhaust sytem and then welded it fully.
its probably as good as any other sports cat system as its more free flowing than the miltek as it only has one 3inch pipe and flange to the downpipe. and the same as a blueflame because thats how they make there system anyway to include the downpipe and decat/sports cat into the 3inch pipework. and even if it isnt its still worth the saving of 350+ quid
on the exhaust itself there is a line of it looks like plasma weld where the tube has been made, i just used this to line it up with. tryed it up against the exhaust sytem and then welded it fully.
its probably as good as any other sports cat system as its more free flowing than the miltek as it only has one 3inch pipe and flange to the downpipe. and the same as a blueflame because thats how they make there system anyway to include the downpipe and decat/sports cat into the 3inch pipework. and even if it isnt its still worth the saving of 350+ quid
Email [email protected] he's a blueflame dealer. Me and rick got ours from him. Let him know I sent you.
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