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Hi people, I have a r32 gtr with a cat back and pfc. Its been tuned quite a while ago but is quite happy but recently i fitted a zeitronix wide band o2 sensor. This has opened up a whole other side of things to look at. I have been doing quite alot of freeway driving and with the help of a friend have been cleaning up the maps around the speed limit area. I have been able to get a noticable gain in response and also smoothness in these areas but the big question is what do people think that the relation between boost and afr's should be? As in if you are cruising along the freeway and the afr is 14.7 either with the standard 02 sensors on or off and you come to a hill what do you think your afrs should drop to with say 2 psi and then 4 and so on? I know people say low 12s is good at full throttle but its the middle im interested in.

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aim for around 14.7 at real low boost (2-4psi) then go gradually towards 11.5-12 at the points where you hit full boost. the afr line from 0 boost to full boost should be fairly linear. everyone has their own opinion but this has worked well for me.

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As far as i reckon you should aim for 13.5 when coming on boost, appaerently its supposed to give the best pressure raise :S Its what i run and works great, other then that i run 15.2-15.3 at cruise and about 12 at full boost :devil:

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