MK5 Golf GTI

All Things Mk5 => Modifications & Technical Area => Performance Modifications => Topic started by: burt2000 on July 30, 2013, 04:08:12 pm

Title: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: burt2000 on July 30, 2013, 04:08:12 pm
There seems to be conflicting views on this and wether or not you can run stage 2 software with a decat dp mated to the oem cat back.

I thought the main restrictions were in the dp (pre cat and main cat) but having spoke to a revo franchised dealer they told me it wasnt a good idea to run a tappered dp with the oem cat back and that i should go full TBE for a stage 3 map

Thing is i dont want the extra noise associated with this and cost of buying a full TBE (£1000+) and really just want the supporting mods which are necessary for stage 2

any opinions form members who have tried this and are running stage 2 with just the decat DP and a CAI on a Mk5 GTI(200bhp)

Cheers :happy2:

Barry
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Janner_Sy on July 31, 2013, 10:40:14 am
Yes you can, I've done yhis personally on my last two cars.  All the performance, none of the noise
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Jaywoo-GTI on July 31, 2013, 10:53:45 am
When i spoke to Kev@Revo he saw no problem with me doing this, so the downpipe is in the garage ready to be fitted.
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: lingenfelter on July 31, 2013, 11:54:40 am
My ed30 has 3" Apr downpipe and OEM catback. Revo stage 2+.
No problem since 2009!
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: burt2000 on July 31, 2013, 12:26:09 pm
Great! thats exactly what im after, the power increase without the extra noise.....loud exhausts arent for me anymore :innocent:
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: berg on July 31, 2013, 07:02:27 pm
you can do it no problems, although i dont think you get ALL the performance.

i ran stg 2+ with just the pipewerx downpipe and then added the full tbe and i could definately feel a difference with the butt dyno as soon as i picked the car up.

but no idea what it equated to in terms of bhp/torque, i just remember Hurdy seeing my car on the ramp at Statllers and saying "that oem catback will be slowing you down"  :grin:
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: ashw831 on July 31, 2013, 09:35:21 pm
I am running the toyosports 3" decat to standard cat back, it sounds epic!!!!! I had some timber hanging out the back yesterday and so had the boot open slightly, didnt realise how good I sounds from the out side.. Was awesome, especially higher in the rev range, I might drive everywhere with the boot open from now on!! :driver:
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: NudgeMe on August 29, 2013, 08:56:42 pm
So would be a better alternative to STD down pipe and aftermarket cat-back system?
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Janner_Sy on August 29, 2013, 09:31:59 pm
but no idea what it equated to in terms of bhp/torque, i just remember Hurdy seeing my car on the ramp at Statllers and saying "that oem catback will be slowing you down"  :grin:

I dyno'd my piper non res cat back with my pipewerx 3" DP before and after and it gave me a whopping 1hp!!!

So would be a better alternative to STD down pipe and aftermarket cat-back system?

If your after more noise but not bothered about power then yes, go for a std DP with aftermarket cat abck.

If your after more power but not the noise then no, go for an aftermarket DP with stock cat back.

If your after noise and power then go for a full TBE.
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: NudgeMe on August 29, 2013, 09:51:53 pm
I'm definately looking for power over noise, I'm not unhappy with the standard exhaust note.

Essentially it'll be cheaper to gain a little power than potentially a lot of annoying (subjective) noise.

Plus my budget wont stretch to a *new* TBE by budget I mean Mrs LOL.

 :fighting:
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: TomGTI on September 09, 2013, 05:29:01 pm
Do you hear any noice improvement running a 200cel down pipe and standard cat back? Im looking for more power better flow and a deeper grawl would be nice? :driver:
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Janner_Sy on September 09, 2013, 05:44:55 pm
yes.  imoit made it sound more like the 2.5T in the Mk2 Focus ST
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: alexoc on November 15, 2013, 07:29:48 pm
My ed30 has 3" Apr downpipe and OEM catback. Revo stage 2+.
No problem since 2009!

Anyone know where to buy the adapters to do this?
I have a 3" Milltek sports cat and want to connect it to an OEM cat-back but obviously it won't fit without an adapter.
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Janner_Sy on November 15, 2013, 07:47:52 pm
My ed30 has 3" Apr downpipe and OEM catback. Revo stage 2+.
No problem since 2009!

Anyone know where to buy the adapters to do this?
I have a 3" Milltek sports cat and want to connect it to an OEM cat-back but obviously it won't fit without an adapter.

Ebay

http://www.ebay.co.uk/itm/T-Bolt-Hose-Clamps-TBolt-Supra-Heavy-Duty-Pipe-Clip-Exhaust-Silicone-Stainless-/330653154359?pt=UK_DIY_Material_Nails_Fixing_MJ&var=&hash=item4cfc76bc37 (http://www.ebay.co.uk/itm/T-Bolt-Hose-Clamps-TBolt-Supra-Heavy-Duty-Pipe-Clip-Exhaust-Silicone-Stainless-/330653154359?pt=UK_DIY_Material_Nails_Fixing_MJ&var=&hash=item4cfc76bc37)

http://www.ebay.co.uk/itm/3-to-2-5inch-stainless-steel-exhaust-flared-reducer-adapter-connector-tube-pipe-/251366028686?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3a8695358e (http://www.ebay.co.uk/itm/3-to-2-5inch-stainless-steel-exhaust-flared-reducer-adapter-connector-tube-pipe-/251366028686?pt=UK_CarsParts_Vehicles_CarParts_SM&hash=item3a8695358e)
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: akbarirfan on November 15, 2013, 08:25:27 pm
What's the difference between a tbe and a downpipe+cat back exhaust?
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Janner_Sy on November 15, 2013, 08:29:46 pm
All GTIs have a TBE as standard, its just not a performance TBE.

TBE = Turbo Back Exhaust.  Made up of two parts  1: Turbo> Centre of car = Downpipe & CAT.  2: Centre of car>tail pipe = Cat back exhaust

When people refer to a TBE they mean a full performance exhaust system from the turbo all the way to the tail pipes. 
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: akbarirfan on November 15, 2013, 09:44:17 pm
Ok thanks, so that means that could have a downpipe from one company and a cat back system from another company, providing that both are performance parts, that would class as a performance tbe.
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Janner_Sy on November 15, 2013, 10:45:13 pm
Yep
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Scrubadub on November 18, 2013, 04:35:10 pm
i made 264bhp with stage 2 revo, 3" decat and standard system
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: fuscobal on December 14, 2013, 04:12:02 pm
I'm have a similar question but for a different situation. My car is stage 3 with about 380hp & 475Nm. I already have a Milltek full TBE but it's 2.75" (at that time there was no 3"). I wonder if by changing only the DP from 2.75" to 3" I will see any improvement (power, response, lower EGTs & higher engine reliability...)
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: roughd on December 22, 2013, 08:48:58 am
Yes you will
A 3" exhaust system will produce less back pressure
You will see better top end
Title: Re: Who's running stage 2 with a 3" decat/downpipe and the oem catback?
Post by: Eddie07 on December 22, 2013, 11:14:32 am
Yes you will
A 3" exhaust system will produce less back pressure
You will see better top end

+1 but add potentially "feels" like less power lower down the rev range.