mk2 gti exhaust upgrades

[gldgti]

hey guys,
my mates mk2 gti is in need of some new exhaust bits due to rego and we're wondering what sort of pipes you guys are running.

can't afford new headers but we were thingking get rid of everything from the headers back, and install new 2.25" pipe with maybe a hotdog halfway and a rear muffler. what do you guys think?

also, who has a cat (not the feline type) and if you do, is it original. have access to a 2.5" cat from a newish merc, which i thought we could get put in aswell if it was necessary.

cheers

aydan

[ausgolfer]

Depends what year and engine it had and what market it was made for.

If it's an Aussie delivered 8v car 90 model onwards it'll have a cat and require one. (aussie cars from 86 onwards have to have cats)
My car is a 89 16v intended for the german market, was built to run on leaded hence was built without a cat. But has since been upgraded.


As for pipe size I would have said no bigger than 2.25"

[gtipete]

hey guys

I'm the owner of the golf in question here....

It's an '91 8v Australian delivered 1.8.

Does anyone know if you can use a cat from another car?

Cheers,

Pete

[h100vw]

2 and a quarter will be plenty big enough. Mine was that big on my G60. I recommend you retain the rear 2 boxes as a minimum. I had a stainless made which deleted the cat as it wasn't required.

They only fitted the hotdog and back box. I was banned from taking the eldest nipper in the car il it was sorted out. It did sound funking smart though. :0)

I took it back and had a 3rd silencer fitted, diagonal in front of the axle, which did the job.

After a good beating at Castle Combe the baffles unwelded themselves in the hotdog so I had it swapped for a piece of pipe. That was the last trouble I had with it in 3 years.

If you didn't already need the exhaust I would say get the headers as they make a fair difference in power. Taking sliencers out doesn't usually increase power, just noise.

Gavin

[Golf Loon]

You can use a cat from another car. Make sure you loose the big rectangular silencer (the suitcase) though. It seriously restricts flow and the car will sound and go bettre without it.

[twin eng, twin turbs]

The Aussie delivered GTI's have a restrictive manifold and single downpipe in comparison to the euro GTI's twin exit manifold and dual downpipe which is worth an extra 10hp+ when coupled to a sports exhaust. Its an option if you wanted a cheaper allternative to extractors. 2" is the best option size wise as you will not loose any low down torque and it will still flow the top end of an 8 valver without serious mods. Go for straight through glass wool packed mufflers, they are relatively quiet down low but give a great raspy note when your up it!

[gldgti]

so let me get this straight:

> need a cat
> 2.25 good size

that car already has the duel downpipe manifold (same as on my diesel).

what about mufflers? do we really need 2 or will a nice rear box do, with a hotdog? from my experience, a decent length hotdog cuts out a fair bit of volume - that and a rear box seem to work really well on the 2" system in my diesel.

so, one muffler or 2?

[evorobin]

I originally had a 2.25 straight pipe with a backbox. Bit loud so had a hotdog installed and now it's perfect. Forget the cat.

[ausgolfer]

Unfortunately being the car that you have, legally you have to have a cat. They don't restrict flow much, the only reason people whinge about them is a cost, as a high flow stainless jobbie can set u back upwards of $300.

If you do decide to make your car louder with the use of less mufflers, you're more likely to attract unwanted attention, and if they look under your car and don't see a cat you could be up for big bucks in the form of a hefty fine.

Personally I think the induction noise on the vw motors is a better thing than the exhaust note. So I'd like a relatively quiet free flowing exhaust with some nice induction modifications.

[gtimk5]

And it is very easy to end up with exhaust drone inside the Golfs which is fine for a short time but can grate on your nerves after a while and make driving uncomfortable.