Threw my car on the dyno to see where was it at with all street tuning. Well 250 was not what I was hoping for but oh well its a learning process. Engine is a S5 T2 with pineapple racing large street port. Exhaust ports are ported so they open earlier, car has a solid idle @ 800rpm, Stock s5 turbo with swapped compressor wheel to a T04B "super S" according to the sizes in the fc3spro site. Boost is what ever it feels like it on a stock ported wastegate (wastegate isn't connected to any pressure/vac port). It has never been over 14psi. Fuel provided by megasquirt 2 v3 with 550 primaries 1600 secondaries and a walbro 255 pump. Exhaust was a 2.5" straight pipe. Does this seem reasonable to you guys? max timing advance under boost is 13*. I have it tuned rich just to be safe. My guess its running out of turbo what you guys think?

 

I'd say thats about right. It makes good power until the turbine stops flowing at higher RPMs (see how the boost drops after 5k?) I managed to put an external wastegate on a S4 manifold so it holds better, by using a stiffer wastegate spring. Then I picked up a turbo with a clipped turbine wheel and now it holds at 15 psi all the way to redline.)

This was my hybrid stage 1, you can see the gauge visibly dropping. I think the needle straight up and down is 15 PSI.

 

Always hated why boost drops at higher rpm. Kinda want to do external wastegate and t4 turbo to solve that problem. Ultimately my goal would be 400whp.

 

Saw this car on the dyno. Sounded nice and clean.

 

I updated the exhaust to dual greddy mufflers. Sounds even better. Anyways here's the video. http://youtu.be/IwJRW1iAyQg

 

Get a legitimate boost controller and it'll probably make the car feel a whole lot better and help out in the top-end. But those numbers don't sound to bad with what you described.