Subaru Impreza Sti Spec C Twinscroll Twin Scroll Downpipe Down Pipe Project on 2040-parts.com
Hicksville, New York, US
I decided to sell my twinscroll downpipe project.
This is suitable for someone that has a GD body, 2002-2007 Subaru Impreza WRX Sti and has an exhaust that is not JDM. If you have a USDM or any other than JDM midpipe and muffler (catback), then the length of this downpipe will be suitable.
All the components here, except for the hanger are unused, new. The hanger is in an as-new condition.
The reasons I decided to begin the project are:
-The downpipes available for twinscroll applications are beyond ridiculously expensive
-The diameters of these downpipes, many of which are over $500 are not even close to 3". When they describe them as 3", in fact that may or may not be the outer diameter. Sometimes they forget giving you the diameter completely, but remember to charge you $800 for the cost of ... a pipe.
-Some of the more affordable downpipes neck down to that factory donut, so as t "fit to the exhaust with no modifications". Why have a $500 pipe, if you restrict it's diameter back to stock, at the far end?
-Some of the remaining offerings are JDM length, so you have to extend them 4" to make them fit a USDM car, ridiculous after you pay that much.
-Nobody seems to have counted how many oxygen sensor bungs they should give you: The Twinscroll EJ207 has the main oxygen sensor AFTER the turbo, so that takes the bung on the bellmouth housing. Then there is the rear bung for the rear oxygen sensor. But where to install the wideband? You don't get a viable answer, after spending a ridiculous price for this pipe.
So I set out to make my downpipe, by buying a USDM length single scroll 3" stainless downpipe. This has a 3" outer diameter, but right there is better than most twinscroll offerings.
I also bought a kinugawa cast bellmouth twinscroll unit. While this looks good, it turns out to have unbelievably thick walls. This may be good at heat retention but necks down the inner diameter to less than 2.6", at the area where you need it to be the largest. Also, the shape of the opening of the bellmouth has to be gasket matched, as it's not close. I did this.
I came up with cutting this bellmouth in an area where it's cross section is still large and slightly oval. I think the equivalent oval cross section came in slightly over a circular 2.7". This is now close to the inner diameter of the remaining 3" pipe, from the USDM downpipe. I then flared the neck of the downpipe, to fit over the bellmouth outlet. Very difficult with stainless steel, to flare it out, basically hammered it.
I got an additional bung welded at the far end.
I bought an OEM hanger, I cleaned it up and fitted it, mocked it up on the pipe (but never had this welded), since the manufacturer of the ebay generic single scroll downpipe "forgot" to install a hanger.
I got some rough welding done for the bung and the neck and then having the unit finally in one piece, was able to test fit it to my 2002 WRX body. It fit!
At this point, I decided to make this into a catalyzed downpipe. So I bought a 100cpsi converter in a 4" unit, the biggest flowing unit available. I began fitting this to the downpipe and cut a section of the downpipe, to make room for it.
FYI: All the big names, especially a Zerosports, etc, if they are "Jasma compliant" have a quite dense converter, that proves to be a restriction, as high as 400 cpsi. Even an APS converter has more than 200 cells per square inch. Godspeed? 200. To go to a brand name with 100 cpsi, you have to go to a Milltek or H&S.
I since threw out the section I cut, but still have a small section I had cut from the bellmouth.
Anyway, I never fitted it successfully after this, because it seemed I had cut 1/2" too much at one end.
So, this can be easily put together by someone that has welding skills and a welding machine available. I did not have any, had to use a meineke and pay for every welding session.
If you don't want to make this catalyzed, you can buy this kit cheap, and get a section of 3" pipe welded instead.
Here is what is included:
-the bellmouth, kinugawa welded to 3" stainless downpipe section.
-the rear of the downpipe, with the extra bung welded
-the gasket for the far end flat flange, where the midpipe connects.
-the stainless bolts that go with these
-The OEM hanger bracket, that needs to be welded to the pipe
-The 4" 100cpsi catalytic converter, metal substrate
The welds that I had done (paid for) to the bung and bellmouth are low quality and need to be gone over, by a welder that has the time to put into these.
With this said, I will begin this at a really low price, because these are taking up room in my garage. By the time everything was added up, new downpipe, new bung, new bellmouth, OEM used hanger and welding, my cost was over $300, before adding the expensive catalythic converter.
There is no warranty, the sale is final, there are no returns.
Exhaust Pipes & Tips for Sale
- Chrome exhaust tail pipe 6 inch x 20 inches duramax diesel international mack(US $99.99)
- Porsche cayenne turbo 957 07-10 tequipment style exhaust tips audi q7 vw touareg(US $280.00)
- Car exhaust tip stainless steel us seller! free shipping(US $12.99)
- Stianless steel downturn tailpipe 2.25" new techtonics tuning vw audi(US $24.99)
- new nos jeep cj mopar chrysler renault amc tailpipe(US $17.00)
- Headman headers(US $95.00)
Nissan NV200 concept (2007): first official pictures
Tue, 24 Jul 2007By Tim Pollard First Official Pictures 24 July 2007 09:19 Nissan NV200: the lowdown Nissan loves a barmy concept car (remember the Bevel, showcased at Detroit for older bob-a-jobbing builders?). And motor shows don't come much nuttier than Tokyo's bi-annual celebration of technical innovation and limit-pushing design. So it seems natural that the Japanese car maker has saved up a special treat for its domestic show this October.
LaFerrari commanding £1 MILLION premium – and the McLaren P1 and Porsche 918 Spyder attracting premiums too
Mon, 04 Aug 2014LaFerrari commanding £1 MILLION premium Being at the top of the new owners list for a very desirable, and scarce, car can yield big benefits, and none more so recently than for Ferrari’s hypercar – the LaFerrari. Oracle Finance has been busy looking at the premiums being charged for desirable cars (and, presumably, willing to finance to premium too) and have discovered that those not on Ferrari’s VIP list – and therefore not invited to buy a LaFerrari from Maranello – are willing to pay a premium of £1 million to get their hands on Ferrari’s replacement for the Enzo. But it’s not just LaFerrari that’s commanding hefty premiums.
Happy birthday, Alfa: Party planned for June and you're invited
Tue, 20 Apr 2010After launching a new Giulietta to celebrate its 100th anniversary, Alfa Romeo will continue the party June 26-27 with a huge rally for owners of its vehicles. The global gathering will be held in Alfa's hometown, Milan, Italy. More than 3,000 participants are expected to show up, and the festivities will include a rally through downtown Milan (filmed by helicopter), concerts and the presentation of a sculpture.