need help tunning my car! help

hey every one i have a 84 gti with the factory block forged pistons and rods with arp and cometic head gasket joining the 16v head on it rebuilt with a hotter set of cams titanium top retainers heaver valve springs shod be good for about 9000 rpms custom intake manifold fitted with a 80 mm throttle body 42lb injectors aero motive regulator 255 walbro fuel pump custom exhaust manifold connecting a hy35 turbo which is off of the dodge Cummins gated at 8pis for right now 3 inch down pipe all the way out 3 inch glass pack water to air intercooler and zex nitrous kit with a 45 shot on it and a electromotive Tec 2 engine management unit but i am having trouble with tuning it does anyone have any tricks or suggestions for me?  or better then that any timing charts for the 16v motors?