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Author Topic: Decatting my car  (Read 5725 times)

Offline Hurdy

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Decatting my car
« on: November 10, 2009, 11:20:30 am »
So, I've finally decided to get the car de-catted to free up some extra ponies and decrease spool up times.

Regal estimates 7-10 bhp extra.

Spoke to REVO this morning and the 2nd Lambda sensor isn't an issue if you are already rocking a stage 2+ remap as it allows for the sports cat/decat sensors :happy2:

Also they say that I will notice a significant amount of extra urge in the midrange through quicker spool up and less back pressure and a more urgent standing start :evilgrin:
Just what I need for the qtr mile stints.

Best of all - £100 fitted for a stainless insert with proper flanging to swap the cat and decat sections for track and road :notworthy:

I'll also get it back to Noble's to see what the differences are with just the decat over my last run a few weeks ago :happy2:
Golf R gone.

Offline cuprak1

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Re: Decatting my car
« Reply #1 on: November 10, 2009, 11:23:29 am »
I thought a decat V sports cat actually didnt give much if any bhp atall, and infact is worse as it doesnt keep some of the vital back pressure needed?

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Offline tony_danza

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Re: Decatting my car
« Reply #2 on: November 10, 2009, 11:28:46 am »
A long read on the subject

Decats are very amusing, apparently... :innocent:
Sideways yo!

Offline cuprak1

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Re: Decatting my car
« Reply #3 on: November 10, 2009, 11:32:35 am »
A long read on the subject

Decats are very amusing, apparently... :innocent:

Wow. good read! still going through it but cheers  :congrats:

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Offline tony_danza

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Re: Decatting my car
« Reply #4 on: November 10, 2009, 11:36:27 am »
I'm not fully up to speed on the matter, but it's interesting reading.
Sideways yo!

Offline jonnyc

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Re: Decatting my car
« Reply #5 on: November 10, 2009, 11:36:37 am »
Sports cat to de-cat isnt a huge difference.. I really doubt the 7-10bhp to be honest..

The biggest thing you will notice will be quicker spool and a more raspy exhaust note.. Still well worth doing though
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Offline Hurdy

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Re: Decatting my car
« Reply #6 on: November 10, 2009, 11:45:50 am »
Sports cat to de-cat isnt a huge difference.. I really doubt the 7-10bhp to be honest..

The biggest thing you will notice will be quicker spool and a more raspy exhaust note.. Still well worth doing though

For £100 it would be rude not to at least have a go :happy2:

If I only get quicker spool up it would still make a positive difference to available power and torque at any revs along the rev range, if not at the top :jumpmove:
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Offline tony_danza

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Re: Decatting my car
« Reply #7 on: November 10, 2009, 11:47:15 am »
I too doubt power hikes, however in a few weeks I'm on the same rollers as it was on when running S1 this time last year, so it'd be interesting to see how I've changed. Spool up RPM, power tail off, graph shape etc.. the figures themselves I think are pretty much meaningless.

Oh, and the 'zorst sounds like it has a wasps nest up there - goes from fizzy to screamy with extra loud Jonny style DSG bangs.
« Last Edit: November 10, 2009, 11:49:37 am by tony_danza »
Sideways yo!

Offline Hurdy

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Re: Decatting my car
« Reply #8 on: November 10, 2009, 11:47:26 am »
A long read on the subject

Decats are very amusing, apparently... :innocent:

Just going through this, Confuscious he say - velly intelesting :laugh:
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Offline Hurdy

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Re: Decatting my car
« Reply #9 on: November 10, 2009, 11:48:44 am »
I too doubt power hikes, however I'm on the same rollers as it was on when running S1 this time last year, so it'd be interesting to see how I've changed. Spool up RPM, graph shape etc.. the figures themselves I think are pretty much meaningless.

Oh, and the 'zorst sounds like it has a wasps nest up there - goes from fizzy to screamy with extra loud Jonny style DSG bangs.

DEFINITELY going on then :evilgrin:
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Offline tony_danza

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Re: Decatting my car
« Reply #10 on: November 10, 2009, 11:52:37 am »
Ha ha - I've non-res, so the sound pressure wave just goes inrestricted all the way before booming in the backbox.

I kid you not when I say it sounds like a rally slag. It is however silly loud in all honesty, I should buy a res section.
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Offline Greeners

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Re: Decatting my car
« Reply #11 on: November 10, 2009, 11:54:10 am »
I like the sound of this!  :evilgrin:

Can I ask the obvious question? What happens come MOT time? Will you have to keep swapping between the two pipes?

Offline MAT ED30

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Re: Decatting my car
« Reply #12 on: November 10, 2009, 11:56:05 am »
if vosa hear it your fooked  :sad1: but the chances of that are slim but then again so many people run de cats now it would be rude not to

Mods yes but way too many to stick in this little box

Offline Hurdy

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Re: Decatting my car
« Reply #13 on: November 10, 2009, 11:58:30 am »
I have a freindly MOT tester Nath, so would only need to change it when I want to :wink:

Matt, I'd obviously only use it for trackdays and 1/4 mile days :wink: :innocent:

Mike, I'm fortunate enough to have the resonated zorst anyway :happy2:
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Offline tony_danza

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Re: Decatting my car
« Reply #14 on: November 10, 2009, 12:03:22 pm »
Track days only, Mat - fortunately Milltek make them so well, they come off and on in minutes  :wink:

Still passes noise regs at <101dB with no probs, but gives me a bit of a headache towards the end of the day.
Sideways yo!