Re: reducing lag via exhaust efficiency

[Gerard <gerard@poboxes.com>]

> So the downpipe is single, might benefit from an increase 2.5" -> 3" -
> then it has to split to go to the stock cats (or not...?). Who wants
> to start making 3" 3B downpipes? I want one to go with my future fancy
> EM. How big is an MC-1/-2 downpipe?

If one makes the 3" from the turbo outlet backwards, won't one need to
fan the piping in some manner from the 2.5" outlet? I remember from
several months ago a thread on the list indicated a gradual fanning
out of the pipe to get to the size of the new outlet (2.5" -> 3") sees
the best results. On my MC (first gen, 1 knock sensor, K26) the exhaust
system in stock form is 57mm (2.25"), but I think my downpipe is shot.
I was thinking of having a new one made by a local exhaust place, but
then I thought of the WG corrugated pipe and looked at what they did
to my new exhaust and I thought I'd better not get them to touch
anything closer to the engine.

As for EMs, anyone made a custom EM for there turbo-equipped 200 or
5k? Just looking in a book I got on a friend's account from the
university about turbocharging cars and there is a bit on pulse
turbocharging and designing EM for best performance. Also got some
book on engine design and there is a bit on inlets, but those
equations!!! Eek.

G.
-- 
"a thousand miles from here, there is another person smiling"
1990 Turbo (200t, MAC13A ECU, 1.4-1.6 bar (1.8 bar with faulty WGFV!),
FWD auto)
name   : gerard van vught
tel    : +27-21-696 0331 (h) / 082 923 9609 (cell)
url    : http://www.poboxes.com/gerard/
e-mail : gerard@poboxes.com  / han.solo@galaxycorp.com