SMEC Fuel Trim logging

[Jason89]

I am running 2.5T2, Stage 2 Turbonetics Turbo-(set at 20lbs boost), 52mm throttle body, 2-piece ported intake, TU Exhaust header, 88TBI Cam, 52lb injectors and 3 bar map.
Do I start with scaling the injectors to 58lb?
And then I would need to reset my Full and Part throttle tables etc?

Thanks Brian I appreciate your help.
Jason

[Aries_Turbo]

when you rescale what you have for a larger (numerically) injector size, it scales the Part/Full/Baseline fuel tables.

Save a copy of what you are running now and then when you rescale, start with the first file so you arent scaling multiple times as there could be some rounding errors if you scale the same file over and over again.

You can scale to 58, but, for safety, I would add some fuel in the middle RPM range of the pumping efficiency just in case. once you get the autocals pulling less, then you will need to retune the PumpingEfficiency table.

Brian

[Aries_Turbo]

id add fuel in pumping efficiency from 2500-4500 range looking at some of your afr values, when you rescale to remove some fuel.

Brian

[Jason89]

Brian,
Do favor scaling the injectors over reducing the fuel psi with the AFPR? I have one one the car. I was just thinking that it is better for the fuel pump if I reduce the psi.

Thoughts?
Thanks

Sent from my LM-V405 using Tapatalk

[Aries_Turbo]

you can do that, especially for a quick test. for the long term, I would run the pressure that the injectors are rated to flow at.

Now for a flowy build with ported manifolds, headers, good headflow with a cam, lower fuel pressure will limit how much power can be made.

if you can reduce pulsewidth in software at the areas that it should be reduced at, you can ramp it back in when needed. with less fuel pressure you are limited in fuel flow even when the pulsewidth is maxed out.

Brian