Make your own downpipe for MK1 A1 chassis - PIC HEAVY! - IDI Engine - VWDiesel.net The IDI, TDI, and mTDI source.

• Make your own downpipe for MK1 A1 chassis - PIC HEAVY! by regcheeseman on 30 Mar, 2009 08:37
• Start off with a 180 mandrel bend, they typically come with one end longer than the other
  
  Cut off the long leg at a slight angle, you want the pipe to exit the turbo at an angle to achieve the clearance required
  
  Weld on a flange – you can use the original one. With all the welding on this job, you need to do a lot of trial fitting to get it right, eye the job up, tack and check it. Oh watch out for the manifold studs, you need to be able to get a spanner on them!
  
  Cut at 45 ish degree and rotate the cut off section through about 180 degrees and weld it back on – you need a bit of a dog leg, so check and tack up first.
  
  Next step is fitting the 90 deg bend to return the pipe to point towards back of car – you may need to fit a small section of straight or angle the pipe slightly to get the pipe in the right place – I aim for the side of gear selector tunnel.
  
  There, pretty much done – I add a 100mm section of straight then a flexi then another 100mm section. It’s up to you.
  
  Here are a few pics of my first pipe fitted up to engine so you know roughly how it should look….and some of my later ones….
  
  
  
  
  
  
  
• #1 by lord_verminaard on 30 Mar, 2009 12:43
• Wow!!!  Thanks for that, very nice DIY!
  
  I'm guessing a Mk2 will be a very similar design?  I will have to tackle this sooner than later- you just made it look much easier than I had first thought.
  
  What sort of welder did you use?  Looks like TIG.
  
  Great stuff, thanks for sharing.
  
  Brendan
• #2 by regcheeseman on 30 Mar, 2009 15:29
• yep all TIG.
  
  I did have access to free stainless and a TIG, about the only perk of that particular job - but I've moved on. Would love a TIG at home.....
• #3 by rallydiesel on 30 Mar, 2009 15:56
• This is why this site is so great!
• #4 by regcheeseman on 31 Mar, 2009 02:28
• would it be of use as a sticky or FAQ?
• #5 by 1outof5 on 31 Mar, 2009 04:49
• Thanks Reg ! Whish I had your skills to do it myself.
  
  Great stuff (that includes the diesel tach/rev counter mod)
• #6 by lord_verminaard on 31 Mar, 2009 06:24
• Quote from: "regcheeseman"

  would it be of use as a sticky or FAQ?

  
  
  Ya, i'd say so, especially since nobody is making downpipes commercially anymore.
  
  Brendan
• #7 by FoXBoXRaCiNG on 01 Apr, 2009 08:02
• Props  
• #8 by Dr. Diesel on 01 Apr, 2009 17:00
• Make sure you brace that badboy against the engine block, triangulated-like. Nice job!
• #9 by RabbitJockey on 01 Apr, 2009 17:06
• Quote from: "lord_verminaard"

  Quote from: "regcheeseman"

  would it be of use as a sticky or FAQ?

  
  
  Ya, i'd say so, especially since nobody is making downpipes commercially anymore.
  
  Brendan

  
  
  false techtonics tuning makes them, but damn they are 345 now,  might as well have a shop do it for you at that cost.
• #10 by truckinwagen on 01 Apr, 2009 19:58
• hell, I have built a couple in the dorm parking lot with a 110 arc welder and an angle grinder with a cutoff wheel.
  
  they didn't look as nice as these (mostly due to the fact that an arc weld on thin steel looks like poop no matter how good it is) but paying any more than $150 is just crazy when you can buy a little welder and the materials for less than $200(and then you have a welder to fix and build anything else you might want later)
  
  super good looking downpipes by the way, much nicer than the ones I built.
• #11 by dankcorey22 on 30 Jun, 2011 12:25
• Will this Work with 2.5" pipe?
• #12 by R.O.R-2.0 on 30 Jun, 2011 12:39
• Quote from: lord_verminaard on 30 Mar, 2009 12:43

  Wow!!!  Thanks for that, very nice DIY!
  
  I'm guessing a Mk2 will be a very similar design?  I will have to tackle this sooner than later- you just made it look much easier than I had first thought.
  
  What sort of welder did you use?  Looks like TIG.
  
  Great stuff, thanks for sharing.
  
  Brendan
  

  
  mk2 will have 2 more bends to clear the steering rack since its mounted on the subframe, instead of on the unibody..
• #13 by fatmobile on 30 Jun, 2011 23:53
• That looks great but I like the idea of supporting it to the block,
   I use the early 4 into 2 into 1 downpipe supports,
    that bolt to the bock and trany,
    just before the flex.