Hondata

So here is the set up:

Built B20 8.8:1
B16 head w/ Type R internals
Edlebrock Victor X Mani
GT3076R Turbo
Tubular Ex. Mani
1000cc Bosch
Walbro 255
Stock Fuel lines
AEM rail & reg (set to 30-32psi)
E85 fuel
s300
Boosting 26psi (boost cut 28psi)

Had the car tuned last late March, early April (in AZ), when the ambient temps where somewhere in the range of 85-95 degrees. The car ran great after the tune with 520whp and the injector duty cycle was around 85-90%. Did a project on the car and finally got it back together and running. Now it is January and the ambient temps are around 65-80 degrees when I drive it. Now with the colder weather, I am hitting my boost cut in 4th and 5th and maxing out my injectors to 100%. I am maxing out duty cycle around 6000rpm and 20+psi and my wideband is starting to lean out.

My tuner says that I can hit 100% duty and still be getting enough fuel. If i continue to climb in the RPMs (rev limit is 8300), the engine feels like it is misfiring (or detonating). My tuner also thinks that the cooler, denser air is not a factor.

My question is this: is the colder air/weather a factor? Do I need a totally different tune for the winter? Am I maxed out on my fuel pump? Is it safe to run the injectors at 100% duty cycle? Isn't there an air temp compensation built into the s300 for situations like this?

If all else fails, I am thinking that I need to upgrade the fuel pump, bump up the rail pressure, and retune. I have added a couple datalogs. Please let me know what anyone thinks. Thank you in advance.

Why is your fuel pressure so low?

If you were at 90% duty cycle in hot temps then you will be even closer to 100% duty cycle in cooler temps. Check your fuel presure when this is happening, and look at your wideband readings.

That fuel pressure is what my tuner set it at. I think it is to get the most out of the Walbro 255 pump. Can that pump put out more at higher rail pressures, or do I need a different pump to raise the rail pressure?

If I retune it for the colder weather and run the duty cycle to 85-90%, will it adjust itself when the weather starts to warm up?

And is it safe to run at 100% duty cycle as long as I am not leaning out? Just seems like 100% is pushing it. And if you look at the datalog, it's not like it just creeps up to 100%. It pretty much shoots off the charts.

no calibration posted

I have turned the settings in the boost by gear WAY down due to my lean condition. Other then that, this is my last tune settings.

YOu have the injector size set to 900 instead of 1000 and have an overallfuel trim added of 25%, this is probably why it is showing you are at 100 % duty cycle. I would recommend takign this back to the tuner to have them fix this. Also your fuel pressure is too low. The walbro 255 is a high presure pump and it is running below stock fuel pressure at this time. Fuel pressure should be between 45 and 50 psi.

O.K. thank you for your time and help. I will be back with results.