Has anybody experimented or tried a D-valve (sorry dont know the proper name.) Its installed right before the throttle body and allows the engine to pull air from the atmoshpere instead of the turbo. Once the turbo starts to build boost it shuts the Dvalve. From what I have read it helps with turbo lag by quite a bit. My question is how would this effect tuning with MS or LH? Im doing a +T on my sons 240 and aiming for lot of bottom end power. Anyways here is a link to what Im taliking aboug.
http://www.shelbycsx.com/csx321/buildup/dvalve.htm
http://www.shelbycsx.com/csx321/buildup/dvalve.htm