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Model specific boards => Golf mk4 => Golf mk4 TDI => Topic started by: alex160 on 06 January 2013, 14:37

Title: Large bore or stick to standard?
Post by: alex160 on 06 January 2013, 14:37

Ordering a decat this month but do I go for a Hoffman decat which is standard diameter or a milltek large bore diameter? Which will give better gains? My golf is a 130 which has been remapped and egr removed, thanks

Title: Re: Large bore or stick to standard?
Post by: Hoggy on 06 January 2013, 16:20

I would go big bore but what is the rest of your system? Standard or bigger bore?

Title: Re: Large bore or stick to standard?
Post by: alex160 on 06 January 2013, 16:36

Well I would probs get a custom made system cat back and get it as a 3 inch system, I have been told that I need to get a system that keeps good back pressure though as the tdi engine don't like not having any back pressure :a

Title: Re: Large bore or stick to standard?
Post by: Hoggy on 06 January 2013, 16:40

If your going custom then go for the big bore decat.

A decent backbox will give you enough back pressure ;)

Title: Re: Large bore or stick to standard?
Post by: tdi_blu on 06 January 2013, 20:06

My CAT was cut off along with the back box it's a straight pipe all the way think its 2.5 inch bore makes a great sound.What difference does the performance CAT make over just cutting it off?

Title: Re: Large bore or stick to standard?
Post by: Rhyso on 06 January 2013, 20:15

I had the Milltek on mine mated to the original system for a bit until I went for a full stainless system

On mine the decat freed up a few extra lbs ft and a couple of bhp across the range.

There are some graphs in my old project page showing the difference before and after  :smiley:

Title: Re: Large bore or stick to standard?
Post by: tdi_blu on 06 January 2013, 20:30

Mines s/s would the de-cat on mine do the same as performance cat?

Title: Re: Large bore or stick to standard?
Post by: Rhyso on 06 January 2013, 20:33

Quote from: tdi_blu on 06 January 2013, 20:30

Mines s/s would the de-cat on mine do the same as performance cat?

Performance cat is a waste of time on a derv. They dont need the cat to pass the MOT  :wink:

I didnt think a performance cat was even available anyway  :huh:

Title: Re: Large bore or stick to standard?
Post by: tdi_blu on 06 January 2013, 20:36

Got ya that's all I was getting at so really with the derv your better off just having it cut off what I've done thxs for the reply  :wink:

Title: Re: Large bore or stick to standard?
Post by: gt130dave on 30 January 2013, 12:01

HOW MUCH WOULD A FULL 3IN STAINLESS EXHAUST COST APPROX 130TDI

Title: Re: Large bore or stick to standard?
Post by: scarr89 on 30 January 2013, 13:56

£200 I guess, straihgt though no back box. My guess...

Title: Re: Large bore or stick to standard?
Post by: gt130dave on 30 January 2013, 15:47

Dont sound to bad be nice to find one at that price  :grin:

Title: Re: Large bore or stick to standard?
Post by: Hoggy on 30 January 2013, 18:28

Have a look on ebay..plenty to choose from"

Title: Re: Large bore or stick to standard?
Post by: jimmybryan on 08 February 2013, 23:48

hi, i had a full stainless 2.75`pipe straight through, cost £140 at unique exhausts stafford, he done a top job! no silencers and he used the flange that was of the old downpipe, it screams on boost and owls a bit to much for my liking, but i weighed my cat in for £70 so all in all i got a brand new stainless exhaust and fitted with a lifetime guarantee for £70.  :shocked: