My questions are about tuning and what kind of scale the A/F is.

1) What kind of scale is the A/F ratio (constant, linear...)?
A) So this way if you had HPTuners and not a Dyno you could set it just by going from idle to WOT?

Basically I'm looking for a good explanation of if and how you would use hptuners without a dyno and a good understanding of the A/F ratio. As well is it more beneficial to dyno and tune if it is possible to tune without a dyno? Lastly is it more advantageous to tune it yourself vs. buying a pretuned chip like intense because you may have things like an aftermarket exhaust, header, intake, etc...?

Thanks so much, sorry it was long but I like thorough explanations so that I can learn and understand.

 

A dyno comes into play when setting up the timing map. You can get the a/f dialed in with a wide band and some sort of datalogger pretty easily but for max power you won't feel 4-5whp difference in a couple of degrees timing just by driving around. That and once you get the timing right the a/f will change.

The stock O2 sensors are calibrated to be very accurate at 14.7:1 a/f but max power is somewhere between 11:1 and 12.5:1, values that the stock sensor can't tell from 10:1. they only know it's rich.

A good dyno though logs the a/f ratio at specific rpms as well as power and torque. It's like having a very detailed map and GPS instead of a compass and word of mouth directions. Sure you can get there either way but one is faster and easier.

A tune for your specific car is always better, especially if you have a local reputable tuner. Every car is slightly different/

 

Thanks.