Bit of bent pipe - increase in performance or not???

[LVC]

I've a Magnex 3.5" rear box, Raceland 4-2-1 Manifold and Magnex de-Cat pipe on my VTS and am thinking about ditching the mid box and replacing with a Cat-back straight through pipe.

Quastions:

1. Is this a good idea?
2. Will this effect the performance (either way)?
3. I assume this will increase noise levels (this is what I'm after)
4. Will any Cat-back pipe fit (with a bit of DIY where it meets the rear box as Magnex rear boxes connect further down the pipe but use a split/slide and clamp fitting).

Can't seem to find easily a Magnex one (I've emailed Magnex) but have found this one vie FleaBay >>>

http://cgi.ebay.co.uk/Saxo-VTR-VTS-Sportex-Exhaust-Race-Tube_W0QQitemZ290531336097QQcategoryZ38786QQcmdZVi ewItemQQ_trksidZp4340.m263QQ_trkparmsZalgo%3DDLSL% 252BSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BFI CS%252BUFI%252BDDSIC%26otn%3D8%26pmod%3D3504356907 87%252B350435690787%26po%3D%26ps%3D63%26clkid%3D69 48742862059828305

Anyone know anything about them ??

[LVC]

Just found this being advertised about 2 hours drive from me - guy wants 30€ for it ... I've asked him what diametre the pipe is as the magnex system is 50mm and I don't want to go any smaller.

It's a full pipe - from Mani to back box - so less joints to worry about ??

http://193.164.197.50/images/138/1383817260.jpg

[jonathon5]

that will do the trick

looks like the rear mount bracket is missing

noise will be louder & you may gain a couple of horses

[Liam_]

I would leave it as is imo.

You'd need to cut that pipe and use a reducer to fit the Magnex.

[SteveWC]

Just buy a supersprint centre section.

They are straight through and are deisgned with the best possible shape with few bends etc and are under 100 quid.

[Liam_]

Just buy a supersprint centre section.

They are straight through and are deisgned with the best possible shape with few bends etc and are under 100 quid.

Rip off for what they are - they go rusty in no time at all, and it's going to need chopped to fit a Magnex backbox to it.

[LVC]

Does no one do a Stainless Steel centre section pipe ??

I was going to go for the one I found but the guy never replied to emails nor calls and now the advert has been removed .... so I guess he sold it - back to the drawing board.

[saxovtsmad]

ive got 4-1 mani cat decilenced centre section and magnex

[LVC]

ive got 4-1 mani cat decilenced centre section and magnex

Where did you get the "decilenced centre section" from ??

[KamRacing]

Just found this being advertised about 2 hours drive from me - guy wants 30€ for it ... I've asked him what diametre the pipe is as the magnex system is 50mm and I don't want to go any smaller.

It's a full pipe - from Mani to back box - so less joints to worry about ??

http://193.164.197.50/images/138/1383817260.jpg

not mandrel bent so there are restrictions to flow at the bends.

[KamRacing]

Rip off for what they are - they go rusty in no time at all, and it's going to need chopped to fit a Magnex backbox to it.

They are not stainless so its inevitable, the aluminised coating will always get breached under the car eventually due to knocks, aggressive road salts, stones and other debris. They are thick enough though that they will still last as long as the owner has the car. If you want shiny buy stainless steel though theres not a massive need considering no-one can see it.

[saxovtsmad]

Where did you get the "decilenced centre section" from ??

had it made at work mate and its stainless fits directly to the magnex

[LVC]

had it made at work mate and its stainless fits directly to the magnex

Don't suppose that your offering to make me one .... lol :hug:

[titchster]

My 2p...

I had a 'straight through' pipe on my car, which I swapped for a Magnex 'Pugsport', which had a centre silencer. As soon as I did, there was a noticeable increase in torque (both me and a passenger noted it straight away). I'm not saying it will be the same in your case, but there's the possibility that you could lose torque by ditching the silencer.

[Liam_]

I totally agree with the middle box thing - I noticed the same when switching from a Magnex with no silencer in the centre pipe to a Piper exhaust with middle box.

At WOT, there was probably nothing in it, but around the doors, the throttle response improved.

[LVC]

Thanks to all for the good advice :y:

I've decided to de-cat as planned but keep the middle box for the moment - too many other projects on the go to faff about with modifying bits of pipe, especially when there's a chance I'll be disappointed with the performance as an end result.

[KamRacing]

most performance centre pipes are straight through inside the silencer meaning they have little effect on bhp or torque. On a normally aspirated engine the pulse tuning is done in the manifold so all the exhaust has to do is get the gases out quickly and quietly. The only way they will move torque significantly down the powerband it will need to be a smaller bore than standard, optimising low rev power but hampering top end.

[LVC]

Thx Mr. Kam - I don't know what make the centre section is but don't think it's a Magnex one, however the pipe diametre leading to and from the centre box is the same as the Magnex pipe and the Raceland mani (50mm I think).

I'm changing the CAT at the weekend and will see if I can see a name stamped on the centre box.

[SteveWC]

Nobody here seems to have pointed out that it looks alot like a standard mk2 VTR centre section? No need for centre silencers as they had a huge dirty cat in the manifold - correct me if im wrong.

Makes me think this due the bends in the pipe, they arent smoothly done to have any effect on performance, just looks like it was made to serve a purpose like a standard citroen pipe.

And if that is the case, chances are youll lose power coz the pipe will be piss thin too.