Forum for competition engine enthusiasts. RIP Guy Croft 09/11/2020 - This forum will continue both as a source of information and as a memorial to Guy.
The new A/R .73 turbine housing is here, compared next to the old one A/R 1.06.
The difference is pretty big, may be near 1000 rpm earlier spool will be :)
Unfortunately this evening the gearbox gave up.
I had boost creep issues with the Turbosmart 38mm wastegate together with the new 0.73 A/R turbine housing.
The boost was uncontrollable above 5000 rpm and I lost it few times up to 1.8 bar.
And a strong rattle and scratching noise appeared, obviously from 2 nd gear, the 1 st gear started whining too...
A lot of work has to be done.