I am getting turbo compressor surge; how do I fix it?

I am getting turbo compressor surge; how do I fix it?

There are at least two kinds of compressor surge:
1. the intake path is being too restrictive so the boost is hitting too much back pressure causing a surge
2. -or- the turbine/turbine housing is mismatched with the exhaust flow such that the exhaust is out flowing the compressor pushing it to the left of the surge line. You can see this at higher RPMs.

For #1:
– If having your throttle closed cause a surge or boost spike, then I think you blow off valve is not working correctly. Using a recirculating blow of valve is normally the best.
– if your BOV is working, then maybe there is a restriction in your intake path.

For #2:
– if you are getting boost creep, you could consider porting out the waste gage hole turbine section so that it is smooth a little bigger. Make sure the flapper still shuts it off completely when closed.
– you can also try a bigger hotside, or external wastegate
– a bit of compressor surge here may be acceptable