Make a donation

Author Topic: BCS decat vs sports cat  (Read 7701 times)

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: BCS decat vs sports cat
« Reply #15 on: October 26, 2016, 09:46:29 pm »
Guaranteed the de cat is louder than the sport cat which should be obvious in sound as there's no restrictions with the de cat.
That was my thoughts too I assumed it would be louder with a decat as it is straight through pipe! Just really confused and don't want to spend out on a sports cat and still be too loud!


Sent from my iPad using Tapatalk
have you got a resonator fitted before the back box?.
Yes I've got the powervalve sports system so it has 2 resonators, one with the valve and the other next to the down pipe!


Sent from my iPad using Tapatalk
wow and you're still saying it's too loud?.
I have a BCS DP and sport cat linked with a link pipe into milltek catback and I'm finding it way too loud as there's no resonator on the cat back.

Offline Martin_jk

  • Always Involved
  • ****
  • Thank You
  • -Given: 19
  • -Receive: 8
  • Posts: 176
    • Email
Re: BCS decat vs sports cat
« Reply #16 on: October 26, 2016, 10:00:07 pm »
Guaranteed the de cat is louder than the sport cat which should be obvious in sound as there's no restrictions with the de cat.
That was my thoughts too I assumed it would be louder with a decat as it is straight through pipe! Just really confused and don't want to spend out on a sports cat and still be too loud!


Sent from my iPad using Tapatalk
have you got a resonator fitted before the back box?.
Yes I've got the powervalve sports system so it has 2 resonators, one with the valve and the other next to the down pipe!


Sent from my iPad using Tapatalk
wow and you're still saying it's too loud?.
I have a BCS DP and sport cat linked with a link pipe into milltek catback and I'm finding it way too loud as there's no resonator on the cat back.
Yeah still too loud, heard so many people say this system is slightly louder than stock just a nice deep rumble when driving normal but mines a lot louder and very intrusive in the car, but everyone that has said that have had the sports cat fitted on theirs that's what made me think it might make the difference!


Sent from my iPhone using Tapatalk

Offline AJP

  • Global Moderator
  • Just look at my post count
  • *
  • Thank You
  • -Given: 392
  • -Receive: 316
  • Posts: 3212
Re: BCS decat vs sports cat
« Reply #17 on: October 26, 2016, 10:06:14 pm »
You could do with having a ride in a car with a sport cat Powervalve system fitted. One man's 'loud' is another man's 'subtle'.

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: BCS decat vs sports cat
« Reply #18 on: October 26, 2016, 10:08:08 pm »
Do you think so AJP
I agree with the more metallic sound but Remembering the de cat is straight through and the sport cat has the gauze that doesn't allow gases to flow as quick imo so it is a restriction of some sort.
Yes, logically that would seem the case. Physics and that. But... going by my Stage 2 dyno, it made 345lb/ft on the stock pump and pretty much stock everything else. I haven't seen or heard of cars with the same setup but with a decat making significantly more peak or at least enough to say a decat is objectively better. Although there's a chance a decat might make a tiny bit more at higher revs. The Powervalve cats are oversize, to compensate for any inherent restriction. I'd imagine a sport cat that didn't benefit from a good design in order to compensate would indeed be more restrictive than its equivalent decat.

So maybe we're both right
yeah the BCS are massive compared to other cats on the market so possibly compensate for the restrictions and again are loud  :signLOL: the de cat would still be less restrictive as you've mentioned giving more peak power as I've learnt over the years imho that is.  :happy2:

Offline Martin_jk

  • Always Involved
  • ****
  • Thank You
  • -Given: 19
  • -Receive: 8
  • Posts: 176
    • Email
Re: BCS decat vs sports cat
« Reply #19 on: October 26, 2016, 10:10:31 pm »
You could do with having a ride in a car with a sport cat Powervalve system fitted. One man's 'loud' is another man's 'subtle'.
I think that is exactly what I need mate! Would solve this in an instance lol will have to see if there's anyone in the Nottingham area with that set up!


Sent from my iPhone using Tapatalk

Offline Stig_gti

  • Always Involved
  • ****
  • Thank You
  • -Given: 13
  • -Receive: 10
  • Posts: 418
    • Email
Re: BCS decat vs sports cat
« Reply #20 on: October 26, 2016, 10:12:19 pm »
What system is louder prestige or powervalve I had a tb prestige system on my old car with sport cat not loud at all.

Offline Martin_jk

  • Always Involved
  • ****
  • Thank You
  • -Given: 19
  • -Receive: 8
  • Posts: 176
    • Email
Re: BCS decat vs sports cat
« Reply #21 on: October 26, 2016, 10:17:12 pm »
What system is louder prestige or powervalve I had a tb prestige system on my old car with sport cat not loud at all.
The prestige power valve is the quieter one mate, I've got the sport power valve system but is decat not sports cat so wasn't sure wether that was the reason for being so loud or wether it was because it has the smaller silencer being the sport system. That might be my option to go prestige just trying to save the cost of buying a sports cat and a silencer!


Sent from my iPhone using Tapatalk

Offline Stig_gti

  • Always Involved
  • ****
  • Thank You
  • -Given: 13
  • -Receive: 10
  • Posts: 418
    • Email
Re: BCS decat vs sports cat
« Reply #22 on: October 26, 2016, 10:20:26 pm »
Ok mate thanks for that.
Like said above best seeing if someone can take you out in there car first before taking the plunge and wasting your money. Good luck

Offline Martin_jk

  • Always Involved
  • ****
  • Thank You
  • -Given: 19
  • -Receive: 8
  • Posts: 176
    • Email
Re: BCS decat vs sports cat
« Reply #23 on: October 26, 2016, 10:21:51 pm »
Ok mate thanks for that.
Like said above best seeing if someone can take you out in there car first before taking the plunge and wasting your money. Good luck
Yeah I think that's my best option isn't it, cheers mate!


Sent from my iPhone using Tapatalk

Offline Martin_jk

  • Always Involved
  • ****
  • Thank You
  • -Given: 19
  • -Receive: 8
  • Posts: 176
    • Email
Re: BCS decat vs sports cat
« Reply #24 on: November 04, 2016, 10:57:49 pm »
Hi all, just thought I'd say after meeting up with a forum member today I can say a decat is ALOT louder than sports cat on the Bcs sports powervalve system, just thought I would say just in case anyone else is in the same boat as me! Thanks for all the help from people who replied :)


Sent from my iPad using Tapatalk

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: BCS decat vs sports cat
« Reply #25 on: November 05, 2016, 11:18:34 pm »
De cat is obviously louder as it's just common sense as I'll say it again, there's no restriction but thank you for that information as others will find this a great deal of help deciding what they want  :happy2:

Offline Martin_jk

  • Always Involved
  • ****
  • Thank You
  • -Given: 19
  • -Receive: 8
  • Posts: 176
    • Email
Re: BCS decat vs sports cat
« Reply #26 on: November 05, 2016, 11:34:26 pm »
De cat is obviously louder as it's just common sense as I'll say it again, there's no restriction but thank you for that information as others will find this a great deal of help deciding what they want  :happy2:
Yeah I did think that from the start tbh and then when you said it too I was pretty certain just wasn't sure how much difference in noise it made was really surprised, don't get me wrong it sounds awesome on a decat just not practical as a daily! I nearly bought a prestige silencer but changed my order to a sports cat after hearing a forum members system, sounds perfect!


Sent from my iPhone using Tapatalk

Offline r5gtt

  • Just look at my post count
  • ******
  • Thank You
  • -Given: 342
  • -Receive: 334
  • Posts: 5586
Re: BCS decat vs sports cat
« Reply #27 on: November 05, 2016, 11:53:08 pm »
De cat is obviously louder as it's just common sense as I'll say it again, there's no restriction but thank you for that information as others will find this a great deal of help deciding what they want  :happy2:
Yeah I did think that from the start tbh and then when you said it too I was pretty certain just wasn't sure how much difference in noise it made was really surprised, don't get me wrong it sounds awesome on a decat just not practical as a daily! I nearly bought a prestige silencer but changed my order to a sports cat after hearing a forum members system, sounds perfect!


Sent from my iPhone using Tapatalk
im lucky to have the milltek 2.75" or I bet mine would sound even louder than it is now :surprised: but still going to resonate it as I don't like the noise as my daily or in general eitherand that's mho  :smiley: