I will run over a few different ways to tune starting with the least recommended to the most recommended. All will require AFC or other suitable fuel tuning device, will assume that you understand how to your your fuel tuning device, have installed the proper mods for the application and are running a proper fuel pressure. This will also be in laymans terms so that everyone that reads can understand it and will be conservative to protect engines. There are more detailed ways to tune for racing applications but those won't be listed.

Tuning device with EGT sensor:
BAD IDEA but we will run over it anyway.
Find a nice long stretch of highway without cops and traffic. Using 4th gear and a friend to keep an eye on the gauge, push the gas to 40% throttle and have your friend record the readings at every rpm range (this may take more than one trial so don't go to redline on the first trial). Your guage should never read higher than 1600 degreed Fahrenheit. Increasing fuel will make the reading lower, decreasing fuel will make the reading higher. Repeat the process for 100% throttle when you are comfortable with your low throttle settings.

Tuning device with 4-lead o2 sensor:
Using a voltmeter splice the signal lead to a wire that will go to the red(input) lead of the voltmeter. Find a suitable ground and run a lead to the black(ground) lead of the voltmeter. Find a nice long stretch of highway without cops and traffic. Using 4th gear and a friend to keep an eye on the voltmeter, push the gas to 40% throttle and have your friend record volt readings at every rpm range (this may take more than one trial so don't go to redline on the first trial. Your voltmeter should read no lower than .80 for n/a cars and .92 for turbo applications. Increasing fuel will take the voltage higher, decreasing fuel will take the voltage lower. Repeat the process for 100% throttle when you are comfortable with your low throttle settings.

Tuning device with Autometer or other air/fuel gauge:
same as tuning with the 4-lead o2 sensor because these guages will splice to that stock sensor. The only difference between this method and the voltmeter method is a different display. gauge face instead of voltmeter reading.

Tuning device with AEM UEGO Wideband:
Find a nice long stretch of highway without cops and traffic. Using 4th gear and a friend to keep an eye on the gauge, push the gas to 40% throttle and have your friend record the readings at every rpm range (this may take more than one trial so don't go to redline on the first trial). Your guage should read between 13 and 15 on the stoichiometric scale guage face for non turbo apps. turbo apps with stock engines should never exeed 12 while turbo apps with built engines can reach 13.5-14 if you aren't knocking. Increasing fuel will make the reading lower, decreasing fuel will make the reading higher. Repeat the process for 100% throttle when you are comfortable with your low throttle settings.

Using a dyno:
The dyno is the best way to tune. It keeps everyone involved safe if used properly and cops don't care how fast you go on the dyno. Make sure your trust your dyno guys before EVER taking them your car.

Some things to think about:
fuel pressure(FP) – increasing FP will increase fuel intake. If you have a 1:1 rising rate FPR(fuel pressure regulator) or 12:1 FMU(fuel management unit) you will have to account for the rise in fuel pressure under boost so that you do not exceed your fuel injector burst pressure.
Example:
30lbs of boost with a 1:1 FPR. 38Lbs of FP. Injector burst pressure of 60lbs. At full boost your FP will be 68 and your injectors could burst. To fix, either run lower boost or get better injectors.

Injector sizing – overkill is “ok” to a point. If you go too big you won't be able to correct enough to get things right. If you go too small and have to increase the FP to an unsafe level your injectors could burst. It is a good idea to go bigger than smaller but don't put 8 750cc injectors in a car that will be making 400hp.

Monitoring equipment – the best things are an AEM UEGO Wideband not a cheaper one that hooks to your stock o2 sensor (uncluding autometer's version). EGT sensors are ok but aren't a good way to tune. Oil pressure, fuel pressure and boost gauges are always a good idea. The bottom line with monitoring equipment is, the more you have the better it is. There is an “overkill” point with this as well. You don't need weird things like coolant temp or fuel level gauges because your car came with those.

Think of tuning in terms of human health. Lean is ok, too lean will cause death. Rich is ok, too rich is stressful and unfulfilling. Optimum performance is reached in a SLIGHTLY lean condition. On an AEM wideband it would be around 13.5-14.5. However, in 4 cyl cars, leaner causes a slight loss in low end torque. The good things about being lean is that you get better gas mileage and more heat for spooling your turbo. 2 things spool turbos, heat and volume. So by being slightly lean the turbo will spool a little faster. the bad thing about being lean is you risk detonation and making your engine go BOOM!

as always, please correct me if I got something wrong or add info :thumbsup:

when i get around to cleaning up fuel tuning and performance chip topics, this write up wil be included :beer:

what makes autometers O2 gauge better than others? cause all i have to aid in tuning right now is an autometer O2 meter hooked up to my regular old O2 sensor. should i feel better about tuning now? haha

oops, I will have to change that so people don't get that idea.

the autometer guage is better than a $20 air/fuel gauge but not near as good as an AEM wideband. the reason is that the autometer guage splices to your stock o2 sensor. it is the same as using the voltmeter on the stock o2 and trying to tune that way. you can be comfortable with the readings of the autometer guage but don't get too comfortable. being n/a still is a good thing though. you won't blow up as easily, but if I remember right you have a ton of miles on that thing so be careful and stay conservative.

I wil revise the post to add in the autometer a/f gauge

yea the damn thing better be good, i paid 90$ for it lol. more fuel is good for torque in the bottom end, but lean it out inthe middle, then increase fuel again for higher RPMs right?

the factory settings during the low rpms is plenty (0 correction). the middle to top (-6 to -8 correction, but remember every car is different so use your gauge). when/if you turbo these will change. transition into your corrections though, don't just knock it down -6.

1000 rpm 0
2000 rpm 0
3000 rpm -2
4000 rpm -4
4500rpm -5
5000 rpm -7
6000 rpm -7
7000 tpm -8

lol you dont wanna know what mine is set at right now. but i guess its different for different pressures. im using the stock FPR and pressure, and on my NEO i have the bar(?) set at 7in and 7out i think. i had it on 6in and 6out, but it hardly made a difference in ratio. i changed it to 7 and it made a difference. my biggest change is like -17.

way too much correction. BAR is the metric equivalent of PSI. 1 BAR is 14.5psi? something like that. that's why a 3 BAR map sensor is used in many high psi applications

ok so i was wrong, its the sensor select in the NEOs settings. following other guides, i used 6in, 6out and i had to used like -30% correction just to see a difference in my afr. i changed it to 7in and 7out and -17% is pulling it to just in between stoich and rich.

so your telling us to use the autometer rainbow, light bouncing thing as a tool to tune our cars??

the only thing that thing is good for is a paperweight or a light should and a one way trip to the hospital.

I would rather see people use a dynomometer :thumbsup:

i wish i had the money and time to get it tuned on a dyno, but why waste the money for a NA car? a wideband is even a waste for tuning a NA. when i turbo, it wil be a different story though.

1 BAR = 14.07psi

thanks bob. I couldn't remember the exact conversion :beer:

speaking of BAR and such, I went to the local track and saw a Buick Regal GNX running at 3 BAR... I was like WTF!!!

Not to be a pain in the a$$ but I'm pretty sure it's 1 bar = 14.50 psi. I verified at two locations (my TI-85 and an engineering textbook).

This says 14.5 also. ??? This chart indicates 14.5 as well.

damn, guess i was wrong.. i could have sworn it was 14.07. Oh well, i admit defeat

how u get it tune a a dyno what do they do? about how much it cost?