My car is over at XS Engendering being tuned today... (For the second time). They're telling me the turbo is "surging" too much boost too quickly at times. They initially blamed the intercooler. Which was later disproved. Now they're telling me the turbo is "surging" because the turbine is too small given the port size. The ports are a large street port and they're saying because they're so large that it's putting out too much exhaust and spinning the turbo out of it's efficiency range... I thought the 35R was a smallish larger turbo for our cars. Anyone have any similar experiences or ideas on what's going ?

My setup : A-Spec GT35R turbo kit (older one up where the air pump was), Rotary Extreme Large V-Mount, LARGE street port, open exhaust, and all the other bits and pieces I doubt would contribute to the issue...

 

I'd try calling A-Spec to see what kind of results they see from the GT35R and a large street port. I think i'd find someone diffrent to tune your car.

-Alex