I5-Turbo Performance

[Brett N Augsburger <augsbbn@eng.auburn.edu>]

    I have been contemplating upgrading the performance on my 5000CSTQ 
for quite some time now. Currently, it is stock with the exception of a 
K27/K26 hybrid turbo which added about 40 horse(a guess). I have just 
recently joined the list, and have checked most of the archives on this, 
and most seem to deal only with boost upgrades. I would like to know 
just what types of mods people are running out there, and I think I speak 
for a lot of people. I have some specific questions, too:
     1. Has anyone had any success in flattening the torque curve of the 
10-valve? Any secrets for more low-end to mid-range power? Would higher 
compression not help this? Anyone tried higher-compression pistons.
     2. Has anyone tried extrude-honed intake/exhaust manifolds or custom 
manifolds? How about custom exhausts? What diameter do you recommend 
(2-1/2",2-3/4",3")? 
     3. Any luck with head porting without sacrificing low-end torque 
further?
     4. Are modifications to the fuel system (mass air flow 
meter/injectors) necessary or desired for 320+ engines. 
     5. Has anyone tried a larger intercooler or maybe even a liquid to 
air intercooler. I know mounting space is limited.
     6. What about a larger oil cooler, and improvements to the cooling 
system to deal with the extra power?  
     7. What is available from AudiSport and where can I get it.
     8. Not pertaining to the engine, but does anyone know if it is 
possible to retrofit the glass roof from the newer cars that have it into 
an older 5000. I would LOVE to have one, and mines not hardly working anyway.
   So come on guys, lets get off the VR6 and start talking Audi!

Brett Augsburger
augsbbn@eng.auburn.edu
'86 5000CSTQ
'73 Porsche 914