i have a S5 NA streetported with a RB full exhaust.

i was wondering what my a/f ratios would be aroudn right now. i am about to install a S-AFC on the car to see if i need to adjust the fuel when i dyno to try to get some more power at the wheels. i have been driving the car around and power doesnt seem to fall off all the way up to the fuel cut, 8600rpm on the tach however accurate that is.



so my quastion is what do i tune the AFR to on this car, considering i will keep teh stock timign and will want to kepp running the 87 octane gas.



any other suggestions would be great.

 

higher afrs will produce more hp on n/a motors, I believe 13s produce the most hp in n/a applications...

 

http://personal.riverusers.com/~yawpower/carbtun.html

scroll down to the tuning with an oxygen sensor bit



mike

 

Just do something that some dope driving a neon and just got done watching fast and furious would do..."Run it really lean..never wanna go rich...drain some oil....add some NOS MAN...LOTS OF NOS MAN."



(althought i read an article on the new turbo neon. it looks pretty quick)

 

i want NAAWWWZZZZ

 

th new SRT4 neon is badass

 

isn't it running like 20psi??? yeah so that car is at its limit, with the stock motor/turbo.

 

The stock SRT-4 Neons run a 15psi stock..fuel cut will probably be close to 16psi. I'm going to guess that the SRT-4s will develop a bad rep for reliability among the riceboys seeing as how they like to throw on an exhaust and intake as first mods...which will cuase the turbo to run even higher levels of boost and inadvertently rock the stock fuel setup...meaning it will lean out and then go boom! Not to mention, early neons had a headgasket problem anyways...lets hope they've fixed that too.





As for your question...basically, wait till you get to the dyno...start with a higher setting, like 16:1 and run down from there until you get the dyno to read the best numbers...i know most dyno guys charge by the pull so try moving from 16:1-14:1-12:1 something like that. Stock injectors usually only run at about 50cycle anyways, so dont go over 80% on your injectors w/ that SAFC...if you find yourself going over or close to 80% its time for large injectors and maybe an aftermarket FPR. Just my two cents...

 

start at 16:1 woulnt that blow my motor?

i thoguh abotu startign at 12:1 and then goign leaner to liek 13.5 at redline

donno what the low end will need, i hear that they like to run rich on teh bottom

i guess since its ported the VE of the engine decreases on the bottom and increases on top

 

i'd say 13:1 go on the dyno and see where it is happiest