Author Topic: Decat 1.8t  (Read 1671 times)

Offline jman-gti aum

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Decat 1.8t
« on: 03 June 2013, 09:37 »
Basically has eany one ever fitted a decat to the standard 1.8t exhaust, what's the pros and cons and how did it sound, as well as the gains on the dyno. Thanks :shocked:

Offline Wayne

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Re: Decat 1.8t
« Reply #1 on: 03 June 2013, 09:54 »
Will gain very little on a standard 1.8t, once your into remaps etc then it will help but you will need it for the mot.

Offline Jin_C

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Re: Decat 1.8t
« Reply #2 on: 03 June 2013, 10:05 »
Turbo will spool up quicker and you will get a louder slightly deeper exhaust note.
1.8T AGU, K03s, 007p, pipercross panel filter, G60 + VR6 clutch and flywheel, silicone TIP, decat + boost hoses, JOM coilovers

Offline jman-gti aum

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Re: Decat 1.8t
« Reply #3 on: 03 June 2013, 10:46 »
Well off for a remap but I cba with a full turbo back might just decat, want car to be as quiet as possible

jamie16v

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Re: Decat 1.8t
« Reply #4 on: 03 June 2013, 11:11 »
standard exhaust and cat is fine for a stage one map..
pro`s of a decat : more flow ready for big power, standard cat is very restrictive.
cons : you`re gonna get very pissed off changing it over every MOT time.
conclusion: if you can afford a sports cat, get one!

Offline jman-gti aum

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Re: Decat 1.8t
« Reply #5 on: 03 June 2013, 18:37 »
So stick with standard exhaust for stage 1 then as not worth the extra costs

Offline Scott D

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Re: Decat 1.8t
« Reply #6 on: 03 June 2013, 19:38 »
if can live with the hassle or know of a friendly garage then a decat is well worth doing even on a stage 1 generic map will get more power and quicker spool up

standard downpipe is very restrictive due to size, ditching for a bigger bore and decat massively helps flow even with standard exhaust.
2003 1.8T GTI 180 - APR Stage I, S2000 Filter, R-Tech Supersize TIP, Bilstein B12 Suspension, 18" OZ Superleggera, Recaro Heated Leathers, US Spec Rear Lights, N249/SAI/PCV Delete

1.8T AUQ - 241bhp & 286 ft-lb
R-Tech Map, Forge FMIC, SFS Oversized TIP, Ported Manifold, Milltek Turboback non res exhaust, Forge 007p, N249 & N112 delete, SAI delete, S2000 Air Filter, Sachs clutch & Lightweight Flywheel

Offline dom

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Re: Decat 1.8t
« Reply #7 on: 03 June 2013, 21:25 »
Basically has eany one ever fitted a decat to the standard 1.8t exhaust, what's the pros and cons and how did it sound, as well as the gains on the dyno. Thanks :shocked:

Sound will be slightly deeper, dyno gains will be minimal. Do you plan to have it remapped?

Offline davemk4

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Re: Decat 1.8t
« Reply #8 on: 03 June 2013, 21:36 »
i noticed a big difference with 3'' decat fitted car gets going much quicker and turbo noise lush but this is will full turbo back and air filter etc
2001 mk4 GTI 1.8t AUM. k&n induction kit with customer heat shield, 3'' TIP, Forge 007P, Stage 1 map, N249 bypass, 3'' downpipe and decat, 2.75'' Jetex cat back non res, Koni shockers and H&R springs 35mm, dimpled and grooved disks front and back