Adding fuel?

[94z286speed]

I have had 2 different TT chips for 2 different set-ups. Both chips required me to add 7% fuel at wot. This was to keep the AFR correct at the max boost printed on the chip. Does this sound normal? What could cause this?

 

[1fast6]

how much boost? what octane fuel? what's your over all FP with line off? do you have a fuel pressure gauge inside car? If so what's your fp at wot?

 

[94z286speed]

25 psi boost, 98 octane fuel, fuel pressure at WOT 68. 43 line off.

 

[norbs]

When chips are calibrated they are based on a set amount of fuel, you have increased the boost making more HP needing more fuel that was estimated by the Programmer (Eric). If you got it to where the a/f is where you want it, with your adjustments it will be fine. Eric can only ballpark the HP your making wit your current setup.

 

[94z286speed]

When chips are calibrated they are based on a set amount of fuel, you have increased the boost making more HP needing more fuel that was estimated by the Programmer (Eric). If you got it to where the a/f is where you want it, with your adjustments it will be fine. Eric can only ballpark the HP your making wit your current setup.

This is my issue. The chip says 25 psi on it for boost and that is what i am running. So i figured the predetermined amount of fuel should be closer than 7% off. And this is not the only chip that this has happened. Another set up I had needed 7% also. Kinda makes me think that maybe my alky kit is not putting out enough pressure. Or my turbo moves more air than thought.

 

[SCOOBY DOO]

I've had several 5.6 chips from Eric...and I've found he's erred on the rich side each time.

 

[Eric Stage I]

Yes. I usually try to err on the rich side. Most of the time, if its an Alkycontrol kit, I assume the knob is on 6, since that seems to work well for most people. So if you have the number lower, or the pump isn't quite pumping like a new one, then it may be leaner than I intended.
But there could be other variables, like maybe the heads flow better than I expected, things like that.
Eric