I don't know if this will help or not, but last year when we were racing in New Zealand, there are many NZ'ers that were running turbo set ups on their jet boats. If you could hook up with a few of them guys, they may be able to advise you on what is working for them. I know that some of their boats were working real good and they had very few failures during the 600 KM race. There is a link to NZ boating on www.jetboatracing.com.