tino

This may be a stupid question.....

When datalogging, how do I know when my pony is running lean / rich ?

Does anyone know where to lookup a good chart of (Fuel / Air /RPM ) chart ? is there a target ratio that has worked good for you?

Please feel free to teach us (me) "non tuners" how to understand this thing.

I want to be sure that after installing Mods, especially those that tweak the air intake and exhaust, that I am not doing damage to my engine b/c of fuel air ratios...

Thanks!

beaustang

I'm no expert but if the FA ratio was off after installing a CAI for example you would get a check engine light because the Mass Airflow Sensor would pick up the change (if it was out of spec). I'll probably get corrected on this but that's my understanding.

tino

Thanks, I think you are correct.

the engine light is not on, but I also installed a performance tune, so I am not sure if the tune resets or tweaks the FA threshold params.

Once I install the headers and exhaust I want to datalog some runs and see where it falls.... It would be nice to know what ratios are considered safe running thru the rpm range.

I would love to take it to a Dyno for tune but there isn't one arround, so I guess I need to learn some basics before I go and start tweaking things with my predator.

I wonder if there are places that can analyze a diablo sport Log and create tweaks for the tune (sure is not exact science, but I have no better alternatives).....

fazm

you can still run in spec, and be lean. just fyi.

tino

Thanks,

zorminster

Stoichiometric (optimal) f/a ratio is right around 14 if i remember correctly- like 14.2 or something. Running Lean will cause premature detonation. Running rich is safer, but causes quicker carbon buildup on internals. Also will cause a cooler burn inside the chambers.

Get a wideband O2 sensor and gauge to really keep tabs on that if your doing heavy modding. Wideband O2 is a 3 wire sensor, its got a signal, a ground, and a heater wire. It will give you a broader scanning range than a normal air sensor and will give you a sure fire readout that you can rely on.


Edited for accuracy.

tino

Thanks,

I'll look arround. Any recomendation on Mfg?

tino

Thanks,

I'll look arround. Any recomendation on Mfg?

scrming

oops.. you have that reversed... running LEAN can cause detonation....

tino

Thanks everyone,

I am going to order the AEM’s Gauge-Type Wideband UEGO Controller.

Looks really good and it is a way fo me to keep my eye on the mixture since I do not have access to a dyno shop.