2-piece turbo manifold, mity vac

[Bryan Gunn <bgunn@voicetek.com>]

Hi folks,

So did the 2-piece exhaust manifold only come on the 20V turbo motor? If so, 
it moves the location of the wastegate, right? If you look at a 20V turbo
motor, the wastegate sticks up vertically on the passenger side of the 
engine, at the #3 cylinder. Like a sport quattro. On the 10V turbo, it is 
angled back by the firewall. If this is so, there's no way you could use
a 2 piece exhaust manifold with the 10V motor because the intake manifold 
is in the way. You would need the 20V crossflow head with the intake manifold
on the other side. Or are there 2 versions of the 2 piece manifold? I'm 
confused.

A mity-vac is a hand operated vacuum pump. It comes with a variety of adapters
allowing you to connect it to almost anything. It has an accurate vacuum 
gauge on it, and is made from grey plastic. You pump the handle and it sucks.
Or creates pressure depending on how you hook it up. I prefer the mity-vac
to various gasses for finding vacuum leaks because it allows me to 
systematically check the vacuum system line by line. For example, the 
vacuum distribution block on the back of the intake manifold. All the lines
coming off of it are super close together. Ithink if you gassed them with
butane or whatever, you'd have a hard time telling which one was leaking.
I just pop 'em off one by one, stick 'em on the mity-vac, and test 'em. Plus
you can use it to bleed brakes and give yourself hickeys. Definitely worth
the $20 or so at Wal-Mart. I would think the mity-vac would be an essential
component of any Audi owner's toolbox.

The two piece exhaust manifold is super sexy because:

A: It doesn't crack. When you bolt a big long cast iron manifold to an aluminum
   alloy cylinder head then rapidly heat and cool the whole deal a bunch of
   times, something's going to give. Fortunately, it's usually the manifold
   or the studs holding it to the head, and not the head itself.
  
   The two piece manifold is in two pieces, so the pieces have a little bit
   of room to move with respect to each other. This prevents cracking.

B: It flows or scavenges better than the stock manifold. I guess the two 
   piece manifold offers less resistance to the exhaust flow. Not sure on
   this, but it's what I've heard.

A cracked exhaust manifold gives Audis their characteristic "Ticka ticka ticka"
sound when accellerating. It sounds like lifter noise, but usually louder and
never goes away. Depends on how much it's cracked, though.

For anyone wondering, my ur-quattro is an '85.

Later 

-- 
Bryan Gunn                  Email: bgunn@voicetek.com 
Voicetek Corporation          Tel: 508.250.7998
19 Alpha Road                 Fax: 508.250.9378
Chelmsford, MA  01824