Test Details:
The test XTO engine has just completed all our Nizpro Marine Tuning and stage one power development, which comprises of full engine calibration, endurance and validation testing, and emissions testing.
It has a complete service history and has run pump 89 octane its entire life.
Prior to the Ring Free test a leak-down test was conducted.
The engine was brought up to operating temperature and the following leak down numbers were measured and recorded.

The standard Yamaha XTO 425 engine calibration was used for all Ring Free testing.
The test selected was the Yamaha Ring Free shock treatment using 2oz per 10 gallons of fuel (as directed) for a total fuel burn of 66 gallons (250 litres).
The actual mixing ratio was achieved by using the mass of Fuel to Ring Free as this is more accurate due to temperature differences affecting volume.
๐ง๐ต๐ฒ ๐ณ๐ผ๐น๐น๐ผ๐๐ถ๐ป๐ด ๐ต๐ถ๐ด๐ต๐น๐ถ๐ด๐ต๐๐ ๐๐ต๐ฒ ๐๐ฒ๐๐ ๐๐๐บ๐บ๐ฎ๐ฟ๐ ๐ฎ๐ป๐ฑ ๐ธ๐ฒ๐ ๐ฝ๐ฎ๐ฟ๐ฎ๐บ๐ฒ๐๐ฒ๐ฟ๐:
โข Engine had two cold start cycles and warm up.
โข Engine had 6 hot start cycles.
โข Engine was set at 3300 rpm at 119 hp.
โข Total run time 8 hours 55 minutes.
โข Fuel consumption @ 119 hp/3300 rpm was 8.8 G/hr (33.3 L/hr)
โข Direct Injection fuel pressure at the injectors was 2900 PSI on both banks.
โข Low pressure VST pumps @ 55.1 PSI.
โข Engine temperature 204.8ยฐF (96ยฐC).
โข Water temperature 149ยฐF (65ยฐC).
โข Air Fuel ratio 13.0:1 (0.89 Lambda).
โข Exhaust gas temperature 885ยฐF (474ยฐC)
โข Cylinder Mass Air Flow 287.24 Kg/hr
โข Ignition timing 24ยฐ BTDC
โข Camshaft VCT position 22.2 degs
โข Oil pressure 92.7 psi/639.3kpa
โข Intake air temperature 71.6F/22C



