Need some advice..
Iīve got the FPT 6,7-560 engines in my raceboat.
Very similar to the Cummins 6,7 but slightly different bore/stroke and 3150 rpm ceiling vs 3300 on the Cummins.
Also low c/r at 14,1:1.
Need another 50-60 hp/engine to get the boat running the way I want.
That shouldnīt be a problem. But.. Also need more power at low revs to get the boat on plane easier.
That is the issue when you need to go from zero to 100 mph in one gear and have 3150 rpm to play with..
Cool seawater and large heatexchangers/oilcoolers keep the water and oiltemps at ok levels.
The problem is the EGT-numbers. After only a minute at
WOT the EGT,s reach 1350-1400 F.
Then I need to go below 2800 rpm for a while to cool things down.
Depending on seastate the engines are under full load for long periods as enduranceraces can last several hours.
Turbos are Holset HX55WM, gated, 41 psi boost.
Watercooled turbinehousings and T3 waterjacket flanges.
Canīt find any data but measured them:
Comp 100 mm exd, 70 ind
Turb 96 ind, 71 exd
Donīt know the size of turbinehousing. 14? Se pic.
Any ideas out there?