Hi all, been learning for a while and been tinkering with MAF scaling but had an interesting chat with a tuner which has me stumped! and hoping to get some clarification.
I have a 2010 WRX with
stock injectors, a stage 3 ots tune with associated mods and noticed that a tune revision raised the injector scaling from stock 550.67 to 587.20 to correct running rich.
I read a good post on here to never change injector scaling (unless fitting larger injectors) to rectify AFR issues but to correctly scale the MAF instead.
In my view, telling the ecu that more fuel is injecting than actual flow to lean out just seems wrong, but a local tuner said that changing MAF scaling affects timing whereas changing the injector scaling does not?
Can anyone shed any light on this??
I can't find any info or explanation on this, but the tuner said stock injectors actually flow at 565 but Subaru set at 550 to make it safer.
Either raising injector scaling or lowering MAF scaling will lean out AFR raising temps which i guess could possibly affecting timing, so struggling to understand how each method differs! I'm thinking there may be compensations made before/after one or the other but not sure which ones and a couple of my comp tables have been zeroed out.
To me it would make more sense to set the real flow rates / scaling and adjust timing accordingly but there must be a reason for 2 tuners to suggest this tuning method?
Hopefully one of you experts can advise as I'd like to have a go at tuning a slightly larger intake
