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Don't have the AFRs mapped on the dyno sheet but here are some basic pinouts of the AFRs 4th gear:

RPM AFR

3000 13.8

3500 13.2

4000 12.6

4500 12.4

5000 12.3

5500 12.0

6000 11.4

6500 11.3

7000 11.0

7500 10.8

8000 10.7

The engine is an R33 RB26 stock except:

Boost - 12psi

3" exhaust no cat

Blitz pod filters

310 RWHP

Are the AFRs down low too lean? The car makes full boost by about 3500rpm so ideally,shouldn't the AFRs be 12:1 at this point???

I noticed most dyno sheets here uses speed instead of rpm on the horizontal so it's kinda hard for me to interpret them.

Where in the rpm range on full load do tuners aim to get afrs @ 12:1 ???

Thanks again guys.

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stop bumping your thread. and do some research. 10.7 at the top end is actually very rich. to me it just looks like a regular standard ecu with more boost than stock. that is what they do. it's leaner at low RPM as it comes out of cruise (closed loop) mode.

stop bumping your thread. and do some research. 10.7 at the top end is actually very rich. to me it just looks like a regular standard ecu with more boost than stock. that is what they do. it's leaner at low RPM as it comes out of cruise (closed loop) mode.

like i said previously 9 out of 10 dyno sheets here uses speed instead of rpm, so it's difficult for me to read them accurately....

And yes i know the top end is rich. My question: Is it ok to to have it so lean at full boost until about 5500rpm where afrs then come to 12:1 ???

bump... your thread wasnt even there for 3hours... relax.

Anyway - those AFR's sound safe, lots of tuners are going leaner, simple look @ the dyno thread would show it.

CRD and a few others are known for it

he just explained it was safe as above

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