EFI for smaller engines 25 hp 4 stroke

The MFS 25/30 B has a PC connection for diagnostic purposes. In addition to reading the memories for temp, RPM, hours, etc., you can drop out individual spark signals or injectors. But the ECU is not designed to be tuneable in the field. You would need to reverse-engineer and re-write the prom for that. What is it you want to do -- re-curve the ignition, change the pulse width of the injector signals? While possible, probably not practical.

Hi Paul
Thank you for your reply.

The purpose of tuning up this engine is racing.

This race class can have max 25hp engines.
Tohatsu/Nissan 25/30 has the same block. So im trying to buy an 30hp engine.
In this class you can tune up engine with out any limitations.

I have find a small compressor to this engine so i will have higher scav air press.
Also new pistons will be installed and the exhaust duct to be increased.

Now im searching for an new EFI system which allow me to adjust the settings as you mentioned.

I mean a new ECU for this type of engine.

Hi Paul

I have find ECU for bigger engine of 150 hp but those are mainly for Mercury.

Hi Paul
I have find a web site in China called alibaba dot com but those sellers only want to sell.
They dont understand what i mean and what is a outboard engine.
They cannot advice me which ECU and diagnostic tool i need so i can connect a laptop pc with USB so i can access all parameters.
Mike

You need to understand that no one wants you to be able to change the settings so no information exists to tell you how.

Hi
I do agree with you.
But when it comes to racing i have to pass the limits....
Mike

I understand and I am not being critical of you in any way...You just are not going to get any help bypassing the programming from the manufacturers...Ofically Feel free to drop me an email, [email protected] , and I will put you in touch with someone in Japan who may take you to the next step

Sure you can .
Theirs an aftermarket device it has a control knob that you can install that adjusts everything to where you want it running.
sends a false signal back to the ecu lying to it.
Telling it that its still running at spec when in reality it way outta range fuel, air everything is tweaked up to the max.
Its used mainly for improving hole shots and top end.
There was an article in Florida sportsman called 25 hp shoot out or something like that it mentioned tweaking 25 hp outboards.
Its talked about in micro skiff forums as well look hard enough you'll find it. I cant remember the name thought it was dyno ____ something.
I think it was like 3 or 4 hundred bucks.
It had rave reviews when I looked at it a few years ago