Oh how soon I get forgotten when I am not around
I fab'ed up the first turbo system to really get any kind of results a few years ago, and made a walkthrough while I was doing it. Most of the other systems either have been abandoned due to flaws in the dynamics of their design. My car still runs great with a .4 bar spring. I have full ecutune stage 2 with 300zx maf and SR20DETT inejectors, and still use the rising rate 4;1 for good measure. In-car wideband reads 11.0-11.7:1 through the rev range. One oversight of many of the systems is the placement of convergence of the up-pipe. the closer you can move the convergence to the turbo (optimal of 6-18 inches) the more efficient your system will be. PLacing convergences that cause interference can even cross the streams! (ok, someone else has to remember ghost busters too?). Keep the convergence smooth, close to the turbine, and if possible place your external gate
on or after the convergence.
Do not use a small turbo like I did, Im currently looking to upgrade to a T04B-82 (.70 a/r compressor with an .82 a/r t4 exhaust housing) so that I will be getting more than mid rpm umph. Power really drops up when I pull out of the efficencey range with this tiny hybrid. I must say instant spool is nice for passing though.
Walk through is here:
http://www.subaru-svx.net/forum/show...745#post388745