I have a NH 8770 and turbo turbines started hitting housing. I had a turbo for 8970 on sheaf. I checked turbo AR number 8770 was .60 on compressor and .94 on exhaust. 8970 was .50 and 1.14 I put the 8970 turbo on the 8770. Now exhaust temp are higher and I have no low end boost. Any suggestions?