chrisdicko

iTrader: (21)

I bought my car with the exhaust already fitted. It was suppose to be a 3" system.....

Yesterday though, I was under the car for the 1st time, and noticed it isn't a full 3" system

The down pipe is 3", then the decatted centre is 2.5", then the rear section is 3"...although the rear section as been cut, and a reducer type thing put on so there is about 30mm of 2.5" welded on to this, which also has the flange on.

What effect will the 2.5" have on performance? And as I'm going for 400bhp very soon, will the 2.5" section need replacing? If it does, can I get a 3" section inc the flange for the rear section?


Thanks a lot
Chris

dunx

iTrader: (3)

I did, my TSL system MAY have proved restrictive, so I went for an APS 3" de-cat.

dunx

P.S. I would think any decent workshop could sort yours.

chrisdicko

iTrader: (21)

Cheers mate


I think it will be easy buying the 3" centre section. But I imagine getting a 3" flange, with a small piece of 3" pipe on it to weld on to my existing exhaust won't be too easy to find?!

Henrik

iTrader: (5)

I'd get two 3" flanges from e.g. merlin motorsports, a piece of 3" tubing and make another flange personally.

The flanges are quite expensive, though (around 26 quid + VAT, I believe). You should be able to find 1m of 3" 304 grade tubing for about 20 + delivery.

Alternatively, you can cut the whole mess out and replace with two sleeve's + some 3" pipe - might work out cheaper than welding flanges etc on.

chrisdicko

iTrader: (21)

Would I not need 3 flanges?

Two for the centre pipe, and one for the rear section pipe? The make a new centre section with the two flanges and long piece of 3" pipe, then cut the flange off the rear section (also cutting the small piece of 2.5" pipe off), then weld a small piece of 3" pipe on to the existing 3" pipe, and then weld the final flange on?

stevie1982

iTrader: (16)

to be honest I think for 400 you will be best for a 3" system. And in all honesty a 3" decat centre can be had for fifty quid on eBay and a 3" back box for 80-150 quid depending on make and if you get caught in a bidding war. It will save all the messing around and you will have a true 3" system. One thing I have worked out in the 4 years is there is no point cutting corners as you will regret it in the long run and no doubt replace the cut and paste pipe work at a later date

chris_bobuk

iTrader: (1)

Chris there is the group buy on hayward and scott exhausts till end of this month.
Think the 3" center pipe is 80+vat maybe worth a look.

chrisdicko

iTrader: (21)

Yeah, I don't want to cut corners to be honest.


Cheers chris, I will have a look at the GB

chris_bobuk

iTrader: (1)

only other place I can think of is the exhaust place over darlington. Or there is one at brotton but not sure If i'd use them never seen their work

chrisdicko

iTrader: (21)

Think I would rather buy one which other people have used before to be honest.

chris_bobuk

iTrader: (1)

Can't blame ya really, I just ordered mine off them on monday

Henrik

iTrader: (5)

I'd just remove the whole 2.5" section and mate a 3" tube directly onto the rear section (as it's been messed about with already), hence two flanges Seems the cheapest way to me

However, that of course means that your exhaust will stay "custom", although that's not a terrible thing anyway.

joz8968

iTrader: (13)

This should fit:-

http://cgi.ebay.co.uk/SUBARU-IMPREZA-TURBO-CENTER-MIDDLE-SECTION-EXHAUST-3_W0QQitemZ350180728452QQcmdZViewItemQQptZUK_CarsP arts_Vehicles_CarParts_SM?hash=item350180728452&_t rksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1 |240%3A1318

...3" bore - but with OEM-size 2.5" flanges at both ends to mate to your d/p and your rear section.

chrisdicko

iTrader: (21)

joz, I've got a 3" down pipe though, so I don't think the flange would fit would it?

I see what you mean as well Henrik! Didn't think of doing that

joz8968

iTrader: (13)

My apologies - I assumed the d/p had a 2.5" flange (as many do) - so yours is obviously a genuine 3", flange and all.


Prob the best solution, then.

chrisdicko

iTrader: (21)

Oh right, to be honest mate, it may have a 2.5" flange...I presumed it was just a 3" flange as it is a 3" pipe welded on to it. Or isn't think normal?


Thanks

joz8968

iTrader: (13)

Also - and I might be wrong on this - If you can find a weird centre with a 3" d/p flange (but a 2.5" rear!), then I think you can still mate it up using one of these (item 'G2' @ 3")...

ExhaustsUK: Suppliers of Cobra Sport Performance Exhausts

...instead of the normal OEM wire wool donut gasket. The downpipe flange has elongated bolt holes, so should work.

joz8968

iTrader: (13)

...Or, how about a 3" donut gasket anyway!...

Subaru impreza turbo cat pipe-centre downpipe gasket on eBay, also, Subaru, Car Parts, Cars, Parts Vehicles (end time 27-Mar-09 20:05:34 GMT)

joz8968

iTrader: (13)

Does the downpipe all of a sudden step down in bore size for the last 4 inches or so (sometimes this section is a different colour too)?

chrisdicko

iTrader: (21)

No, it's exactly the same size on the down pipe, but what you described about stepping down happens on the rear section of the exhaust!

joz8968

iTrader: (13)

Right, so you need a 3" flange at the d/p end, and a 2.5" flange at the rear end of the replacement 3" centre-section! It's normally the other way around that you can get centres for i.e. the centres of a 2-part 3" system! (e.g. some Cobra systems or Nur Spec R).

Best get a custom one then...

chrisdicko

iTrader: (21)

lol, it's never easy for me!

I'm half thinking of getting a new rear and centre section, so then it should all match up nicely!! Money though.........

joz8968

iTrader: (13)

This is the 'be done with it' sane option


...And this is always the 'barrier' (...throw enough money around and most things can be resolved ).

chrisdicko

iTrader: (21)