I have a boat with an indmar 310 vortec carb engine. it uses a distributor the same as a efi motor does with no mechanical or vac advance and it uses what looks like a standard 8 pin module what my problem is the timing doesn't advance very much maybe about 5 degrees. the four pin plug that would normally go to the ecu for timing control doesn't go anywhere I am curious to know if the standard 8 pin module has any advance built in to it or if the marine module is different? Thanks Ross

The stock auto EFI modules have about 12 (?) degrees of advance in them. This only happens when in bypass mode, which is when the ECM is not controlling the timing. It is a backup for a dead ECM limp mode operation. This timing comes in between 1400 and 1600 RPM.

There are two ways to go: put in a regular distributor (non-EFI), or use something like a 1227747 ECM as a timing computor with the current distributor.

RBob.

Don't forget about RPMs below 400rpms, this is mostly cranking though. The ignition module ignores computer controlled timing(est line/wire, IIRC).

I think a mechanical distributor would work fine. It'll be a much easier install than a whole engine management system.


Guess you could crank the current distributor around until it runs good, as a quick fix.

I have connected a 808 computer and it connects and runs the timming fine, the only thing is that the distributor is standard in these boats and they are supposed to get about 28 degrees so i'm guessing there must be a different module for the marine motor and they want to charge an arm and a leg for one and i'm still not 100% sure it is the problem.

now these auto modules i see are used in 4 cylinders and v8's so does anyone know how it would tell what application it was in when in bypass mode to know how to give the correct amount of advance?