engine running temp

[Fast355]

i know this isn't the question, but why not find yourself a nice big heat exchanger and get a proper closed loop system going for your engine so you can run a proper operating temp? a big ol' iron engine like that really needs to get a bit hotter to run its best

Actually they do not! The modern 350 Mag MPI and 496 Magnum HO use a 120°F thermostat and runs under 140°F.

[spielco]

I forgot to mention this a berkeley jet drive package that was salt water cooled. I need to satisfy the ecm as 143f is not hot enough. steve

[Fast355]

I forgot to mention this a berkeley jet drive package that was salt water cooled. I need to satisfy the ecm as 143f is not hot enough. steve

There is really not much to altering the tables to make it work with that operating temperature.

There is a coolant temperature based spark modifier table.

There is also a coolant temperature based air/fuel ratio table.

There is also an coolant temperature based idle speed table.

One merely need to adjust those tables to make the value slightly lower than the normal operating temperature the same values as the normal 190-210*F of a road going vehicle. That means you are not adding additional fuel or timing for the cold engine and the idle speed is set to where your application requires.

I am assuming you are running without an 02 sensor in the manifold. You should be able to use a 7747 leaded fuel .bin for an early year model 454 as a good starting point as they ran entirely in open loop and also ran without a knock sensor.

[spielco]

It does have 02 sensor I put a 02 sensor right in the exhaust manifold at the rear exhaust port. By putting 400 ohms across the coolant sensor, when its at 143f the scanner said 178f. Do you think this will fly. It does have knock sensor. Its starts fine and because its a boat, winter cold starts won t be an issue. steve