Leiffi
New member
- Joined
- Jan 31, 2013
- Messages
- 1,381
In Firepunks Youtube video about nitrous they said no one monitors turbo shaft speed because it is too complicated and expensive. Actually it is free if you already own a smartphone. Use Spectrogram or other similar FFT analyzer app to measure sound. Calculate full blades of compressor inducer , measure Hz , divide by full blade count and multiply by 60 to get your turbo rpm. From the screenshot attached, 8 blade HX60: 13000Hz / 8 x 60 = 97500 rpm.