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I am planning to install a AFC neo on my R33 Gts t Series 1, coz it is running really rich.

now here is my query, will tuning the car with an AFC affect the timing? the way i understand how it works is, it restricts the amount of fuel but it does it in such away that the ECU still cranks the timing right up for a rich mixture. wont this stuff my car eventually??

it cant be good having the timing and the A/F mix all wrong can it?

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The AFC's change the Airflow meter signal to the ECU and can not change the ignition timing. It tricks the computer into thinking there is less air than there is in the system so that it does not inject as much fuel, this should only be modified with a wide band o2 sensor hooked up or you can make it run too lean and kill the engine.

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it will be getting installed and tuned at a reputable workshop, so i would assume they would do it with a wideband o2 sensor. last time they had a graph from the dyno with the results of the AF mixture, they will be doing that again after it is tuned so i will be able to see.

but will the timing be an issue if it is tuned properly?

the timing will still be out even if it is tuned properly. right??? :P

i just dont wanna kill my car is all. i want it perfect.

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if you lower the correction value to take fuel out, the ecu thinks there is less airflow and doesn't inject as much fuel, which also makes the ecu not add as much ignition timing. if you raise the correction value to add more fuel, the ecu thinks your flowing more air so it adds more fuel, which also inadvertantly adds more timing.

nothing to worry about though. not unless your at -50% correction on the fuel map at full throttle, which wont be the case. lots of people run AFC's and don't have a problem. keep in mind the AFC is only really good for a mild modded setup.

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The AFC neo, safc and any piggyback without ignition timing adjustment is purely a bandaid for the rich n that rb25's suffer from...and for obvious reasons its best to upgrade to pfc for the best results but if your budget doesn't stretch then yea it will help to a certain degree...pardon the pun.

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The AFC neo, safc and any piggyback without ignition timing adjustment is purely a bandaid for the rich n that rb25's suffer from...and for obvious reasons its best to upgrade to pfc for the best results but if your budget doesn't stretch then yea it will help to a certain degree...pardon the pun.

The tuner should adjust the timing to eliminate any knock. For best performance also get an Apexi SITC to get the best timing across the rev range.

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I only have a pod filter and 3inch exhaust on the car, im just sick of the richness robbing my power.

It is just a quick fix really until i can afford to get a HKS GTRS turbo kit, Greddy FMIC and a PFC, maybe some splitfires and nismo injectors if the budget will allow, which will be a while away so i want something to help in the meantime.

I just dont wanna wreck my engine while im waiting to save up enough cash the upgrades.

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What would be a mild modded setup ? I am having the same problem choosing either the SAFC or the PFC

exhaust, FMIC, maybe a bit more boost. if you have plans for future mods you will be better going for a PFC. also even on mild mods a PFC will still give a better tune than a SAFC.

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I'd go to a PFC with exhaust and FMIC.

I'd only use a SAFC if I only had one of the two mods, and I had no intention of doing anything more to the powertrain than that.

A SAFC is something you do if you plan on keeping the car practically stock but you don't like your rear bar covered in carbon. Like ryan said, its just a band-aid solution.

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ok, so my car will be fine for a year then? i wanna save up enough money to get it all done at once to save on tuning costs.

i havent had the Skyline that long and it seems to be in the workshop all the time, i would like to be able to drive it for a while with no problems, so i can save up money for upgrades.

im hoping the AFC will do the trick and keep me happy for a while. :)

Thanks for the replies guys, ive decided im gonna put it in next week, damn workshop is always booked up. :P

Edited by GreyGTST
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