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slydog

Exhaust design thread...

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when you get your extension pieces made you have the exhaust shop expand the ends of the pipe so that it will slip over you existing tube.  once that is done you can slice a small section from centre where the tubes touch and then run a weld up the middle and around the end of the slip joint.  Job done and no leak.

 

as to secondary length - there are a few theories out there.  Underbody space and size of the secondaries you choose will dictate how much length you can run on the secondaries. 

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Nice work Adrian, but the minimum diameter should be around 0.5" bigger than your primaries and the tail pipe 0.5" bigger than you minimum diameter. So unless you intended on using a 3" exhaust with you 2" secondaries, you probably do not need it and a baffle collector will work.

 

In saying this, if you are only making around 200FWHP, what you have will work, despite you minimum diameter causing a restriction when compared to your secondaries.

 

VenturI merge collectors are only needed when there is a big step in size between your secondaries and tail pipe diameter.

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Ok so most of you know I have been beating on about building a twin 2.5" system with an 'X' pipe for my race car.  Well I have had all these bits for awhile and I finally found some time to get into it so I started with all this today.

 

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I worked out a rough plan and seeing as it was going into my race car I was lucky in that I did not have to deal with the usual constraints of bending the exhaust around to suit the floor plan.  I decided that I wanted the new system to be as straight as possible. Minimal bends - less restriction.  I also wanted to get the new system up as high as I could to avoid track damage as well as damage from unloading and loading the car.  So I checked the rule book and modifying the floor pan to fit the exhaust seemed to be okay and I have seen plenty of people do this - even with exhausts routed on the passenger side of the car.  So I hooked in and removed a section of the floor to allow the exhaust to basically run straight under my seat and back into the original exhaust cavity.  I'll replace this section with a bit of 1.5mm sheet steel bent and swagged for strength. 

 

So I joined the MOROSO spiral flow mufflers and fitted up the flanged turndowns which allows me to direct the exhaust wherever I want.  I decided to go straight to ground.

 

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I worked out the length I wanted before the system met the X pipe and I that allowed me to build the system from the back forward.

 

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Then I spent the rest of the afternoon doing the front half of the system so that it bolted up in the same way as the original exhaust. This will allow me to back to back each of the systems on the dyno to see if the new system has made any power or torque gains. One thing is for sure it sounds heaps better, a bit louder than the original system but for the moment I'm happy. So enough garbling, here is the video.

 

https://www.youtube.com/watch?feature=player_detailpage&v=ehTtPostYjk

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Nice neat setup Ando

Thanks matt.  I'm really happy with the way it turned out and how it tucks the exhaust up out of harms way.  I'm looking at making my own set of 'Header Mufflers' (see Car Chemistry header mufflers) to put into the turndowns to take a bit of the rasp out.  I'll post up some pics after the school holidays and I'll take another video with a better camera and just focus on the exhaust noise at idle and with a rev cause it does sound very sweet. 

 

Thanks again for the kind words.

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