Typical boot pressures for 6BTA 370

[pwrobert]

Just finished installing a couple of electric turbo boot gauges. At dock they both work but what are the typical pressures I should look for at various RPM’s under load when I take her out for a run?

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[pwrobert]

Exactly. Just installed and I could tell that they light up and the needles cycled full scale and back (like VDO tachs) as they are supposed to do when initializing but needles Didn’t do much sitting at dock regardless of RPM as you pointed out. Reassuring. As I expected the load and RPM were necessary to get real readings just wondered what numbers would normal at cruise and WOT with my setup If all was prime.

I mentioned in an earlier post that this is a newly setup repower and I am just getting things dialed in. With your earlier help the boat gets its 3150 RPM and burns 17 gal/hr while loaded for a Bahamas trip where I was able to log fuel used, hours, etc. all manually tracked. Put 50 hours running time on her over two weeks. Recently I installed a Maretron FFM100 fuel analyzer and find that it confirms my calculated cruise rates. 17 G/H at 2300 – 21.5 mph. I hope to check out fuel burn at other RPM settings and see if anther cruise speed should be considered.

Little by little these add ons are getting done just taking me time to install and check them out.
I appreciate your feedback to let me know how my efforts measure up compared to other similar boats..

[Tony Athens]

Measured Boost pressure is a function of exhaust flow through the turbos exhaust turbine blades. Exhaust flow, measured in CFM and is approx 500 CFM per 100 HP produced by the engine ( basically any color diesel engine in this class) .. It is not just a function of the engines RPM………If your engine is 100% to spec, propped out to where is making rated HP, then the engine will flow approx 1800 CFM, produce 355 BHP at 3000-3100 RPM and if all is right, make about 30 PSI of boost measured after the aftercooler.. . Cruising at 2400 RPM, you’d be asking the engine to make about 190-210 HP , burning close to 10 GPH (+/-), flowing about 1000-1100 CFM of exhaust gas and would be making 15-20 PSI of boost.. Every hull loads the engine differently when on plane.

Tony

[Rob Schepis]

Approx 30psi WOT and half that at cruise ( under load–not in neutral) – several factors can effect the actual numbers…
“At dock they both work” ?? What boost could you be measuring at the dock with no load?

[Author]

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