S Afc

[snafer100]

alright i dont have money right now for both injectors and s afc, though im needing them pretty bad, knock sensor causing my engine to come on, if i can just get the s afc for now will that help some?

 

[DookGST]

Yes

 

[snafer100]

ok how should i set the afc i got a 20 g and stock injectors? with extremes cheaper fuel pump, hacked mas, other mods on profile, i wanna get that know to go away

 

[Quacylla]

A 20G on stock injectors? Good luck. Your knock is probably caused by the injectors maxing out. If that's the case even the AFC won't help you.

But it also may be you are just running too lean from the hacked MAF and if that's the case the AFC will be able to help you.

What boost are you running? What rpm are you knocking? What does your 02 sensor voltage plot look like across the entire rpm range?

 

[Turbo Guru]

The S-AFC will only induce fuel-cut faster. The only way it is of use to us is to compensate for bigger injectors (by leaning out.) The addition of a 20G pretty much requires larger injectors.

Joe

 

[DookGST]

remove that honecomb if ya havent already

 

[turbowannabe]

bad idea on the honeycomb removal because that is there specificly to create vortecies without which the mas cannot take a correct barometreic pressure reading!!!

 

[2-0turbo]

Originally posted by turbowannabe
bad idea on the honeycomb removal because that is there specificly to create vortecies without which the mas cannot take a correct barometreic pressure reading!!!

Well, DookGST should have specified "the lower honeycomb". I knew what he was talking about, but others might have not.

But, turbowannabe, the center section works a little different that you describe. The honeycomb straightens the flow prior to the air flowing through the measurement region. The measurement region has basically a small bluff body that creates vortices as the air flows by. These vortices shed alternatively off one side and then the other (standard theory developed by a dude name Von Karman). The frequency of the shedding is directly proportional to the velocity of the air flowing through the metered region. There is a separate air intake measurement and a separate barometric sensor in your MAS. The MAS has a fixed area flow path, so with above computed velocity, temperature and density, you ECU can calculate mass air flow. Removal of the honeycombs would very likely do absolutely nothing to your baro reading.