Cracked rear iron... I think

[ElTeeFauci]

here is a sample datalog, and the ignition and fuel maps I've been using.

Using 550/720 injectors, all freshly rebuilt. walbro 255 fuel pump... haven't had any fuel issues to date.

[RETed]

Originally Posted by ElTeeFauci

here is a sample datalog, and the ignition and fuel maps I've been using.

Using 550/720 injectors, all freshly rebuilt. walbro 255 fuel pump... haven't had any fuel issues to date.

Your fuel injectors are too small.
You only have enough fuel injector capacity to handle about 270 - 280hp, if everything was tuned nicely.
By your datalog, your tune is still all over the place.

Look at the max pulsewidth - 89.4%.
As a rule of thumb, you're not supposed to go past 85%.
Anything over 85% will possibly lock up the fuel injector - basically > 85% is the same as 90%...95%...100%.
You ran out of fuel capacity.
This could be one reason why the engine let go.

Don't bother with the older S4 (rear) irons.
I've broken them on a customer's FC @ 320hp on a Dynapack dyno.
Replaced with an S5 (rear) iron, and it's doing 400+ reliably daily driver.


-Ted