reducing lag via exhaust efficiency

[Sargent Schutt <sargent@novagate.com>]

Frank,

On your sub-4k boost lag issue: I am considering upgrading to a hybrid turbo
and RS2 manifold. First I'm (still) waiting on my Stebro exhaust. It will use
dual hi-flo cats to 2.5" dual pipes with free-flow (no baffles) mufflers
(center and rear). That should reduce back pressure a little. Then the RS2
manifold and hybrid turbo, along with (perhaps this won't be necessary) a
better down pipe (Graydon - would your unit work here? Anyone else got any
suggestions for improvement). I will go with Ned for the chip.  

Question: if you replace the manifold and the rest of the exhaust with a more
efficient, free-flowing system, I would exect less lag from cruise/idle,
though a little faster boost loss with shifts would occur. What is the
collective wisdom on reducing lag vis a vis the exhaust on hybrid turbos?
QSHIPQ? Scott Mo.? Graydon? Anyone else? I know there are other IC and intake
path modifications which will help throttle response and therefore lag, but
what of exhaust mods? Significant lag reduction there, or is it a waste of
money (save the ear candy)?

TIA for any insight/test results/learned thoughts!

Sarge

91 200q