MK5 Golf GTI

All Things Mk5 => Modifications & Technical Area => Performance Modifications => Topic started by: Dundy53 on January 30, 2015, 08:56:53 pm

Title: Need more derv power! advice please.
Post by: Dundy53 on January 30, 2015, 08:56:53 pm
Hey, so I bought a mk5 Golf GTTDi last year, done a lot of cosmetic mods now I'm planning some performance ones and need some advice please :)

Decat - Should I cut the cat out myself & weld it up (anyone got a guide) or buy a downpipe and just replace the whole thing? Would there be any extra power gain with buying one?

Remap - Is there anything I should do to the car besides decat & exhaust before getting it mapped?

Air filter - Should I get a K&N one or any other one for a little extra power? Or just stick to the VW ones..

I'm using the car for work & leisure so I don't want it to be too bad on fuel but also fast & fun.

If any of you have a spare 5 mins to give me some advice that'd be great,  cheers!
Title: Re: Need more derv power! advice please.
Post by: doylebros on January 30, 2015, 09:06:14 pm
Look at member xjay1337 TDI build threads for his current and past motors that's a good starting point, which I found interesting and an educational read.
Title: Re: Need more derv power! advice please.
Post by: Andy on January 30, 2015, 11:34:54 pm
The decat  will make the car rev a lot better  in the  mid range and better mated up to a free flowing  exhaust. .but don't forget with no cat on the car it will fail a mot

The oem air filter is fine and these performance filters on a diesel don't do anything except put a hole in your wallet
Title: Re: Need more derv power! advice please.
Post by: Dundy53 on January 31, 2015, 08:30:52 am
Perfect cheers guys.
Title: Re: Need more derv power! advice please.
Post by: dan930 on January 31, 2015, 11:46:42 am
Who you going to for remap mate?
Title: Re: Need more derv power! advice please.
Post by: TommyR on January 31, 2015, 01:20:57 pm
This would provide some more power! :evilgrin:

http://www.darksidedevelopments.co.uk/products/darkside-gtb-turbo-kit-for-2-0-16v-tdi-bkd.html
Title: Re: Need more derv power! advice please.
Post by: Scrubadub on February 01, 2015, 07:34:37 pm
Cut the cat open and gut it, then re weld up, will pass mot and makes quite a big difference! I cut backbox off aswell and just extended the pipe
Title: Re: Need more derv power! advice please.
Post by: kmackgttdi on February 01, 2015, 09:57:19 pm
i bashed the cat out on my gt tdi 4motion, just make sure u get it all out, I just used extensions and a hammer, as for mot, it's a diesel and they get smoke tested, removing the cat usually allows for less smoke as less particles are caught. They must however have a dpf if fitted. If you put a downpipe or dpf delete pipe on its obvious the cat or dpf has been removed. But they can't phsicaly check inside to make sure it's there. So on a dpf opening and removing it to leave the original pipe and sensors is the best way around it. In the case of dpf you would require a map or to have the function removed as the sensors would know it's no longer there.
Title: Re: Need more derv power! advice please.
Post by: Dundy53 on February 02, 2015, 11:56:11 am
I live in the Scottish Highlands so I think Revo is the best place which is closest to me for remapping,not sure though.

Has anyone got a guide for cutting the cat out? I've already got a miltek cat back so I'm sorted with the exhaust.

My GTTDi is a 140, I don't think they come with a dpf unless I missread somewhere.

Cheers guys.
Title: Re: Need more derv power! advice please.
Post by: xjay1337 on February 02, 2015, 12:10:06 pm
Hey, so I bought a mk5 Golf GTTDi last year, done a lot of cosmetic mods now I'm planning some performance ones and need some advice please :)

Decat - Should I cut the cat out myself & weld it up (anyone got a guide) or buy a downpipe and just replace the whole thing? Would there be any extra power gain with buying one?

Remap - Is there anything I should do to the car besides decat & exhaust before getting it mapped?

Air filter - Should I get a K&N one or any other one for a little extra power? Or just stick to the VW ones..

I'm using the car for work & leisure so I don't want it to be too bad on fuel but also fast & fun.

If any of you have a spare 5 mins to give me some advice that'd be great,  cheers!

Decat - buy a proper 2.5 / 3 inch pipe . less lag from turbo and remove rear silencers with the equal length pipe for a nice straight through system.. or small in line silencer if you want a bit less noise.

remap - yes of course. and put egr delete pipe on at same time. also fit new fuel filter and run with decent fuel , vpower or bp ultimate

air filter - leave it as stock with new filter .. if you want to go open cone then use an s2000 filter and put a proper heat shield on.

makes no differnce economy vs power to be honest, well tuned it will make the same or better MPG when cruising... best bang for your buck is darkside GTB turbo budget kit with a 1756vk on a cast manifold.
think it's £1800+vat drive in drive out service also includes a free service.
stock 2.0 tdi turbos on the BKD engine usually sh*t themselves. no 140bhp PD engined Mk5 Golfs had DPFs
Title: Re: Need more derv power! advice please.
Post by: Dundy53 on February 02, 2015, 04:19:07 pm
Cheers for the reply xjay, very helpful. Where can I buy an egr delete pipe and what difference will it make?

ta
Title: Re: Need more derv power! advice please.
Post by: xjay1337 on February 02, 2015, 04:46:52 pm
save dirty crap air being recycled back into inlet and lower inlet temps as a result. cleaner running engine
they are available on ebay or darksides website.
Title: Re: Need more derv power! advice please.
Post by: kmackgttdi on February 02, 2015, 09:17:03 pm
I was referring to the fact that it will pass mot without cat and that its dpfs that have to be there.
Title: Re: Need more derv power! advice please.
Post by: Dundy53 on February 02, 2015, 10:04:02 pm
Okay I'll order one, cheers.

Oh right I see, the only thing I was worried about buying a new downpipe would be the no cat at MOT issue but if it's only dpf's that matter that's great, cheers.
Title: Re: Need more derv power! advice please.
Post by: Andy on February 02, 2015, 11:53:44 pm
The memo we got sent from vosa stated if the car was manufactured  from new then it should be present when the car goes for a mot
So it should have a cat on as well
Title: Re: Need more derv power! advice please.
Post by: Andy on February 02, 2015, 11:55:38 pm
(https://www.mk5golfgti.co.uk/forum/proxy.php?request=http%3A%2F%2Fi212.photobucket.com%2Falbums%2Fcc20%2Fmaxitrol%2F20140203_124131_zpsafb45411.jpg&hash=89018a61227a5a99da5d80740608b051f30eff3d) (http://s212.photobucket.com/user/maxitrol/media/20140203_124131_zpsafb45411.jpg.html)
Title: Re: Need more derv power! advice please.
Post by: xjay1337 on February 03, 2015, 01:04:10 am
Okay I'll order one, cheers.

Oh right I see, the only thing I was worried about buying a new downpipe would be the no cat at MOT issue but if it's only dpf's that matter that's great, cheers.
Technically you need a DPF but mine's passed without it.. officially the line is "if fitted from factory it must be present on MOT" but 1) it's almost impossible to tell anyway from looking under the bonnet quickly or on the ramp with the under tray on and 2) MOT techs can't go routing around for things.

Darkside sell a "fake" DPF box which would remove this problem altogether.
Title: Re: Need more derv power! advice please.
Post by: Dundy53 on February 03, 2015, 01:06:11 am
Think I'll just cut the cat out myself and save potential hassle/money.
Title: Re: Need more derv power! advice please.
Post by: Matto on February 03, 2015, 06:35:39 am
140's never came with a DPF unless someone spec'd it from new as it was available as a retrofit kit but they are few and far between. You'll have no issues come MOT  :happy2:
Title: Re: Need more derv power! advice please.
Post by: Dundy53 on February 03, 2015, 10:30:07 pm
Just to confirm, this is the pipe I need to get rid of my eve valve? http://pages.ebay.com/link/?nav=item.view&id=130770671294&alt=web

I currently have an engine light on my dash which is egr related, if I instalI this pipe and clear the code will it come back or?

Cheers
Title: Re: Need more derv power! advice please.
Post by: jason_rmh on February 03, 2015, 11:07:44 pm
No. That is just for removing the egr cooler. You don't have to remove that, but might as well while you're at it.
You need an egr delete kit.
Darkside EGR Delete Race Pipe - http://www.darksidedevelopments.co.uk/products/darkside-1-9-8v-pd105-2-0-16v-tdi-pd-ppd-and-cr-egr-delete-race-pipe.html (http://www.darksidedevelopments.co.uk/products/darkside-1-9-8v-pd105-2-0-16v-tdi-pd-ppd-and-cr-egr-delete-race-pipe.html)

To get rid of the ECU light, fit egr delete kit then get the egr function mapped out of your ECU.

Use search, there's a few threads on this as well as a how to guide.

Jas
Title: Re: Need more derv power! advice please.
Post by: kmackgttdi on February 03, 2015, 11:42:19 pm
Have to say that you'd be hard pressed to see mine for a transfer box Prop shaf and undergrad anyway. But I just broke mine down, ( I don't know how diff mine is to 2wd downpipe but I got an extension down into and knocked away with a hammer) and dropped it in the bin whilst I cleaned the turbo vanes. Regardless it's much better, a lot smoother and pretty much no more noise. Could also be the clean turbo lol. And as jay says I'm sure it's technicaly cars with dpf but again it's down to the given mot tester. I mean they can advise for engine covers and under trays but I'd say 9/10 that pass through our workshop don't. I also know that pretty much no 140 came with dpf if any?
Title: Re: Need more derv power! advice please.
Post by: Cossie Killer on February 04, 2015, 12:57:38 pm
So the egr delete is a neat little mod to coincide with a remap and exhaust, again this is on a GT sport (140). 
Title: Re: Need more derv power! advice please.
Post by: kmackgttdi on February 04, 2015, 10:10:39 pm
So the egr delete is a neat little mod to coincide with a remap and exhaust, again this is on a GT sport (140).
Definatly
Title: Re: Need more derv power! advice please.
Post by: Cossie Killer on February 04, 2015, 10:45:59 pm

So the egr delete is a neat little mod to coincide with a remap and exhaust, again this is on a GT sport (140).
Definatly

Cheers, will add it to the list!