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Hi all,

I installed a SAFC on the weekend, its all working well and good, however i haven't set any corrections or anything, its still just "initialised", all i have done is configured it to work and to display information.

now, the problem I have is simply that ... well i dont' know what to do :) ... how do i know what corrections i have to put in?? i dont' have one of them a/f detector things which costs like 1000 bucks ... i wanna give tuning it myself a go, i'm not too worried about engine screwing up as well, i'm running 10 psi with stock turbo and cooler, and i think its only putting out about 150 rwkw or there abouts in an auto ...

my mods are bleeder at about 0.75bar (~10psi, spikes a bit on a cold night), full exhaust and pod.

from what i've seen people post up, it seems people add correction at the very low revs and once on boost the correction is "minused", why do this??

also, will the stock ecu compensate for the corrections by retarding the ignition timing?? which then just makes the whole idea useless??

i've seen powergains as little as about 10rwkw to something like 50rwkw, i'll be happy with about 15rwkw, i know my car can easily do that as i accidentally boosted the car too high on the weekend and the power was ridiculous, i was wheel spinning in first LOL ... too scary for me ... so i put it down ...

It would be nice if people could post up their settings and mods too :)

thanks

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I'm interested to know too hippy! I installed mine and a mates today... They are both currently zeroed out..

The idea as far as I know is to try and get a flat AFR curve whilst on power... Most R33's start to run really rich around the 4500 - 5500 area. That is why you will see most people "minusing" the fuel up high...

"plusing" :) the fuel at low revs may be to aid in bringing the turbo on quicker due to the increased exhaust flow.

The stock ecu will modify the timing as you are effectively using a different area of the stock maps... Whether it retards or advances I'm not sure... A SITC can be used to combat this I believe.

Just my thoughts though... I could be way off. I'd be interested to hear what the "experts" have to say...

Hey strutto :)

He's the guy that installed my S-AFCII today. He did a great job, thanks mate :)

I've been fiddling with all the monitoring settings, this unit is so cool. I havent dared to touch the air/fuel curve yet. Its a great unit though, still trying to work out how to set the knock sensor though, i havent driven it much yet to note what the knock value is yet.

Any info on a generalised air/fuel settings would be great.

well i was just out for a spin ... :) ... yeah i think i need new tyres ... i'm definitely spinning the wheels and going sideways sometimes LOL ... anyways i was just putting it +1 or so and then -2 flat from 3000 rpm onwards ... i dont' know if it did much ... feels sorta the same LOL still spinning the wheels sometimes ... i should go get insurance ... :) .. it looks like we need to get an expert onto here ;)

Hey strutto,

Yeah i realised why the knock sensor didnt move off 0 when driving home. I read the other post where you said how to set it up and its all good now :)

knock level tonight was at 10 when driving. But when i was at idle it goes upto 15-20, but i read somewhere that the idle knock isnt relevent?

  hippy said:
it looks like we need to get an expert onto here  :D

YEP! :headspin:

I just had a go too (slaps wrist for being so impatient)... No F'n idea what I'm doing. Most i dialed up was about -6 at 4000 or so... Made a little difference but not much...

Dynotune here we come!

you can only mess with the settings ON a dyno. its really easy to do yourself though, as the dyno i was on, the operator refused to touch it and said they were "alot of wank, those jap gadgets" i had no experience with it, but figured i had spent some money and wanted to see what difference it made and i played with the settings on the dyno and we did several runs. i ended up not making much more top end maybe 5rwkw but managed to fatten up the mid range by about 20rwkw. the dyno guy was amazed.

the one thing i noticed however, was when adjusting the dips at say 4500rpm on the dyno sheet, an adjustment on the safc at 4500rpm would actually change the dyno reading at like 5000rpm so it isnt the most accurate thing, but with a bit of a fiddle it made some wicked gains.

without a measurement for the air to fuel ratios it's pretty hard to tune perfectly. But not impossible to tune reasonably for some more power than you have, assuming you don't already have really good afrs.

The knock monitor helps a little. The other issue is the base timing, this interacts with the fuel map to determine your limits.

Tuning by ear is a bit of a problem even with the knock monitor, it took me quite some time to get a reliable tune out of mine.

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