4-2-1 manifold. Difficult to fit on mk3 golf gti?

[GTimBACK]

Hi all! I've recently purchased a mk3 8v (agg) golf gti on an r-plate and have been having a few exhaust noise issues. First, the heatshield was rattlin so i had it welded and stuck a jubilee clip round the top edge to stop that. I also had a couple of blowing joints, and these are now, pretty much sorted. Lastly, i'm getting the common rasping noise from the downpipe/manifold area and its really bloody irritating! This rasping will sometimes turn into a popping/spluttering noise further down the system on the overrun. Could this be the cat? I get a bit of vibration from the cat at 2500rpm but if i tap it, i cant hear anything loose!

To get round all these issues, i was thinking of getting one of the 4-2-1 s/s manifolds/downpipes off ebay. access looks a little restricted down the back of the engine, so is there any advice anyone could give me before taking the plunge and buying one? will the head need to be removed, or just the inlet manifold? any advice on decats too? worth the money?

any input greatly appreciated.

Regards...

[saul79]

just the manifold and lower the subframe slightly to clear the rack

[bored_Welsh_lad]

Well well... ive been thinking of one of these for a while now...

i think a DIY should be knocked up if you buy one!!!

[Mikester]

What are the benifits of one of these?

[Len]

Mike - greater flow. So more gases can get out quicker.
On their own they may not be a help as can cause back pressure so need to be done with high end Mods like cams and big valves and trottle bodies.

In most cases a standard exhaust manifold is adequate.

[GTimBACK]

it wouldn't have a detrimental  effect without the high end mods though would it? I reckon my downpipe needs replacing anyway and have been looking at a few prices. I think the cheapest i found was around 55 squid. There was also the local motor factors wanting 135!! yeah right!

I'm probably shooting myself in the foot here by saying theres a 4-2-1 on ebay for £80 'buy it now', but that doesn't seem a bad alternative for the extra 25 quid.

oh and yeah, if it goes ahead, i'll take a few snaps and create a DIY page. It may go something like this.....

1: undo manifold retaining studs.

2: if the studs sheer, give up!

end of DIY.