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Heyaa all,

Im gettin my SAFC II Tune really soon, and read soo much bout a/fuel ratio, lots of people giving me all sorts of figures

from 11.5:1 - 12.5:1.

So pretty simple question,

I want my car to be on a safe tune, so if i were to go out on a cold nite and it lean out a little, it'll still be safe. ( I go out at night heaps )

Mods are as followed:

R33 S1.5

Stock Turbo @ 10psi ( no boost controller )

3" Turboback with no resonators

Pod with shield ( no cai )

Greddy Front mount

SAFC II

Walbro Fuel pump

So from what i gathered from the forums is this wat the a/fuel ratio should be:

Full Throttle - Below 4500rpm - 12.5:1

After 4500rpm - 12:1

Lo Throttle - 14.5:1

With these a/f and my mods you guys recon i will make 190-200rwkw ? Reliablely ???

I never seen partial throttle been tuned on a dyno before ? I only seen WOT power runs, So how do they do it ? Just wanted to know for knownledge sakes.

Any help and advice would be really greatful !

keep in mind you may not get a 12:1 on a safc. you may have to settle for an 11:1. its about finding the balance with a safc.

the more fuel you have to take out of the map (or the more you bend the afm signal), as is the case with most 33's, the more it screws with your timing aswell. take out too much fuel and your ecu may retard the timing too much and you will get knock.

yeah i got an apexi neo afc..

ive had mine tuned wice to get it right, but then i lowered the % of the low throttle..

to increase fuel eco...lol but got it all good..

i get lik 400-500k's outa my tank..

but i change on high-throttle around 2500-3000-3500rpm.. i made 0 % which means no change by the afc/neo

on idle my car is -12% on the a/f ratio %'s..

but its a great product and recommend..

but stil get an aftermarket ecu...

really depends on your usage .

street use then 14.7:1 - 15:1 cruise and 12.5 :1 for full throttle

if using on track then 11.5:1 - 11:1 for full throttle .

if its too lean at 12.5:1 on the track under full throttle conditions than you will produce to much heat and cause undue pinging and under bonnet temp will be significally higher. (known from experience )

but yes you are on the ball park with the ratios that you where given

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