Fuel cut Options

[97TalonTSI]

The talon is running good. Tuning is where it`s at now. My boost creep is under control for the most part the AVCR finally went into self learning mode and seems to be working better but at WOT in 3rd gear I get fuel cut. That is at about 18 psi and around 4800 to 5200 rpms. I know I will have to start upgrading my injectors and ecus stuff at some point but do you guys think the injectors (stock) or my plugs might be causing any of my problems? Also I am running a ported 14b turbo.

[ncgalant]

80%Duty Cycle is the suggested maximum for any fuel injector.  You're probably running about 100-110% currently on the stockers.

This depends on the brand of injector and how large it is. Generally, the larger the injector the more dead time you have, thus you are allowed a smaller maximum duty cycle. For example, a Denso 660 runs 180 microseconds of dead time so I would be comfortable tuning those up to 90% duty cycle. On the other hand Denso 720's run 450 microseconds of duty cycle. I wouldn't want to tune those much beyond 75%. Kinda funny when you think about it. Considering the dead time values, Denso 660's have almost as much high RPM fuel metering capability as Denso 720's.

I you tune an injector with any amount of dead time beyond its duty cycle capabilities you get uncontrolled amounts of fuel from the injector and tuning goes out the window.

A good point to consider. My denso 720s were real fun to tune out with a SAFC, but it can be done very effectively. If you chose to go that route there are plenty of us around that can give advice on tuning. If you are looking to run injectors bigger than 550s and not get an eprom, I'd also recommend an AFPR. That allows you to scale down bigger injectors until you buy a bigger turbo and really need the fuel.