Webinar 011 master fuel pulse setup

Is there a rule of thumb on how many ms the master fuel setting should be due to injector size? I noticed in the webinar he kept the master fuel at around 14ms and adjusted the table to see around 90% at full load. I didnt see him talk about injector size unless I missed that part.

I'm new to tuning and trying to find the proper way to make my base fuel setup. I have a ka24det with 750cc injectors. Curious if I have to use a smaller master fuel setting due to larger injectors and adjust the table equally to maintain the 90% at full load for a base fuel table.

The in application help in Link tuning software actually describes how to choose this. It's the injector on time in ms that you'll get if you enter 100 in the main fuel table.

You can estimate your fuel requirement based on cylinder volume and desired lambda, then calculate injector on time to deliver that fuel based on your injector flow rate.

If you're not yet comfortable with those calculations you can also start with all values in the fuel table set to a medium value like 50, adjust the master fuel value til the engine starts, tweak the master fuel value til you're within 10-15% of fuel target at idle, and then start adjusting the main fuel table from there to build out your tune. As long as you don't end up needing a value too large or small to enter in the main fuel table, that simplified method can work. If you start getting near the table bounds, you'll need to adjust the master fuel value, rescale the whole fuel table, then continue refining your tune.

Alternatively, Link's newer Modeled fuel equation mode makes things easier and in my personal opinion simply better, since the main fuel table is a VE table, no master fuel value is required, just your injector flow rate and fuel pressure along with injector dead time data required with either model.