Fuel Air Ratio

[christo76]

What A/F ratios would you suggest for tuning turbo applications on a rb25det with stock internals with GT3076 running preferably 18psi, for a save everyday street driver?

The optimum A/F ratio for N/A applications is 12.5:1 for best power when rich, and 13.2:1 for best power lean, so somewhere around there (If your intention is to tune it with an SAFC or something for better power or economy). WOT enrichment is generally to protect the engine/engine components like spark plugs. If you were to run a cooler plug, good fuel with appropriate ignition timing, you really shouldn't need as much enrichment, will get more power and better economy. Sometimes when maintaining WOT at high RPM on leaner fuel mixtures, components such as pistons can continually absorb extra heat (while the head and block are cooled sufficiently), that's when you use fuel to cool them. Generally you'd use somewhere at the lean end of the best power for part throttle, and somewhere around the rich end for at WOT, it really depends how high strung your engine is (compression/ignition timing/revs) and how hard it's driven.

[SKiT_R31]

Probably the wrong section, but I wouldn't want it leaner than ~ 12:1 (somewhere around the 11's at full boost probably).

Boosted cars handle richer mixtures better, and require more fuel to cool/slow combustion. I'd leave it upto your tuner but ideally before you play around with it get onto an EGT sensor, otherwise you're really tuning blind and are going to have to tune conservative & rich to play it safe.