Down pipe

[Wrxprt]

Would it be good to simply remove cat converter from down pipe and replace with 3" pipe for more flow or better to buy after market down pipe and just bolt straight to flange ?

[Andy_Mac]

Depends on a few factors. Probably not worth welding straight pipe into the stock one. Just gut it and leave it as it is. Made a fairly big difference to mine for next to no cost. Main factor that determines whether keeping the stock one is viable is whether it has a bellmouth opening or not. The Legacy's all have a flat plate where the wastegate opens so get **** flow. Some of the Impreza ones come stock with bellmouth downpipes. Its not really worth spending money on if it just has a single tube opening.

Thats what the ones with the flat plate up against the wastegate look like.

Edited December 27, 2015 by Andy_Mac

[Wrxprt]

Ah ok so how do you go about gutting it?

[Wrxprt]

I'm a bit new to this that's why I'm asking I've just heard that the converters are very restrictive on flow and with a turbo engine I want as much flow as I can get

[Guest]

Just buy a full 3in turbo back system and write it off as future proofing.

[Wrxprt]

As of yet it's just a daily so I don't Wana spend too much if I could remove or gut cat for less than 100 each then I'd prefer to do that as a down and u pipe will cost me near 700 which I will get around to doing later if I do more extensive modification.

[lachlan]

http://clubsub.org.nz/forum/showthread.php?47791-rangi-decats-a-primapy-downpipe

[Marky]

A downpipe will not cost you $700

Option A) Gut cat as per example above

Option B) Keep an eye out for a second hand one

Depends on how much time you have to kill

Option A is the cheaper one ($free) and will net some gain, option B costs money but will have a better result

[Wrxprt]

Down pipe is 450 on trademe and up pipe is 150 so 600 sorry not 700 haha

[lachlan]

I bought a whole second hand japanese fgk fujitsubogiken turbo back exhaust for $350 .

And a greddy up pipe is about 100 from japan . But I didnt pay shipping

[Guest]

Full exhaust brand spanking is 500 on tm. Tell gerald at strongs to keep an eye out for a v7 down pipe they generally flick them for 100-150.

[Wrxprt]

Ok back to original story plain and simple I don't want to spend 700 on a up pipe and exhaust right now I just want something that can be done in a day cost minimal. And have better flow tiny power gains for next to nothing. In the future yes I will buy a aftermarket down pipe and up pipe and bugger turbo and fuel reg etc and tune. But it will be off the road while I do this all at the moment I want something fast simple cheap I like the idea of gutting it for now. I have a 3 " exhaust system but for whatever reason previous owner left factory down pipe fml.

[Wrxprt]

In Saying2 that if a down pipe came off for 200 or less is claw at it and but it asap . But what I've found is 495 for a down pipe on trademe if anyone finds cheaper ones please let me know link etc. Thanks

[Guest]

Ill try again.

https://touch.trademe.co.nz/motors/listing/view/1003876984

The big up pipes with flexis are junk and decrease performance...

[slystiguy]

advertise on facebook that you're looking for a downpipe. They usually go for around the $100 mark for second hand. Also check out I think it was japrace has a 3inch for $300 or something (new, ill try find link). Rossub has link on his build page I thnk.

I recently had my uppipe re-made - went to exhaust shop and they refused to do it because they couldn't guarantee fitment without the car being there. ended up going to an engineering shop where they did it for $100 just a nice bit of chunky pipe no flexi, works really well.

[Wrxprt]

Ahh that 500 dollar kit looks on my the money also looks like it comes with a.up pipe too only trouble is from down pipe back is already 3 inch but I guess I could just flick that off

[Wrxprt]

In saying that though you wouldn't recommend fitting the up pipe with flexi? Just keep factory one?

[Guest]

Those uppipes are massive in diameter = losses pre turbine and theyre **** quality bad port matching etc.

[slystiguy]

http://www.japrace.com/exhaust-system/down-pipes/down-pipe-subaru-wrx-01-high-flow-1

On special too.