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bosch 1680cc data, wot fuelling isn't consistent.


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hey guys, having some issues with my car. im running bosch 1680cc (indy blues) injectors. it has a gfb reg at 4bar, a walbro 460 with upgraded wiring. my cruise trims are pretty spot on. if i dial in my WOT fuelling perfect, the next day its either crazy lean or crazy rich. i cannot figure this out. fuel pressure raises on boost as it should. does anyone have the data for these so i can see if ive gone wrong somewhere. files attached for a looksie 

HACCEG3 stock no changes 1680cc chasing me tail check trims.tec

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When you say rising rate reg, do you mean a boost referenced reg, eg it holds a flat pressure + boost pressure? Or are you saying its flat pressure + boost pressure * factor. As in the pressure will be more than the base + boost? Eg it is not a 1:1 ratio?

If is above 1:1 ratio I'm not even sure how you'd tune this as it might not be linear. It sounds horrible and I'd highly recommend against this.

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measuring vs boost. i didn't adjust fuelling at all yesterday. just drove it and let it get pretty warm. it started off rich, then got to the point of matching my commanded fuel at WOT. but then i kept driving it. and it got leaner. my commanded is 0.80 lambda at wide open. when it got warmer (driving for two hours straight) it got to 0.84+

something seriously dumb is happening.

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On 12/4/2020 at 5:41 PM, JETURBO said:

How much fuel did you have in the tank at the start of this two hour trip vs the end ? 

what is significant about fuel density vs temperature ? 

what does ford allow for in this regard with a standard calibration ? 


1. ???

2. Same as most stuff that gets hot and cold.

3. Mebbe soak time enrichment is doing it.

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