Your engine is a 230,,, correct????
If it is a .82 A/R then that should be OK.
By opening it up, I mean to open the exhaust passage in, anywhere it narrows/necks down.
If you can get the old housing for free, practice opening/porting on that piece.
Measure the turbine wheel hole size & compare to your .82 housing to see if they are the same.
Get a double cut carbide cutter tappered cone type. 4" long or 6" Like 3/8 diameter or so.1/4" shank
Just before & right at where the exhaust enters the turbine wheel(hits the wheel for making it spin), it necks down the most, check for casting flaws, thin spots, & relieve these areas.
Only other choice is to send out your turbo center section to have the turbine wheel clipped,,,,& rebalanced,,, but doing so,, you will add a couple hundred RPM before you go into boost.Like if your boost comes in at 2200 RPM, it will come in @ 2400 RPM or there abouts.
So if you are not happy w/how the boost comes in now,, I would not suggest to do that.
MBHD
