carb to TBI converions, Marine application

[Fast355]

I see some challenges using a 16168625 PCM for a Marine Carburetor to a Marine TBI conversion. Usually the 1227747 ECM is the Marine TBI computer of choice. The 1227747 has a park switch input, which eliminates the need for a Vehicle Speed Sensor. Setting the 1227747 park switch to Ground (battery -) tells the 1227747 the vehicle is in park. The 1227747 will operate an engine when the 1227747 thinks the engine is in park.

The 16168625 does not a simple park switch input. It might be possible to configure the transmission gear position inputs of the 16168625 to indicate park. (That's something I have not tried to do) The 16168625 uses Vehicle Speed input to select near idle or off idle fuel and spark tables. It might be possible to configure the vehicle speed parameters along with the TPS% parameters to "lock" the 16168625 into using the Off Idle fuel and spark tables only?

I'm sure a Marine engine would run with a 16168625 without a Vehicle Speed input, I'm just not sure how well the engine would run? Perhaps there is a way to have a GPS supply the 16168625 with a vehicle speed input?

dave w

I used the 7427 with a simple park/neutral switch, it is simply a matter of enabling the 700r4 logic. Auto trans/TCC only switches. Input signal on one wire of the 3 (forget which) and it works great.

If it is a Mercruiser several companies make an adaper that sandwiches between the marine manifold and riser and holds an O2 sensor.

I did a TPI 7730 on a TPI marine conversion and simply wired the kill switch into the coil output between the module and coil. Worked beautifully! used a newer marine thermostat housing off a Vortec L31 marine engine thay had the same bolt pattern angle.

7427 works in Open Loop only very well too!

I never use different Idle/Off Idle tables. Would be easy to set the switch over to Zero MPH and disable the Idle parameters completely.