printmanjackson

iTrader: (1)

these may be dumb questions but I have to learn somehow. Why do the software systems need a wideband to tune the car? Is this something that you leave in the car? After tuning how do you know you are improving the engines performance? Do they tell you RWHP and TQ?

ND2RACE

A wideband O2 sensor is what you use to get your fueling dialed in, as for measuring HP and TQ and dialing in your spark you use a dyno. Do yourself a favor and get yourself a book on the topic and start reading, there is a ton of info involved in learning to tune. You'll either find yourself on overload and understand why so many people pay a pro, or ready to jump in with both feet and start learning how. Personally I've been learning for almost two years and have had to overcome quite the learning curve, but its worth it if you can get there.

joecar

To tune, first you setup the PCM to only run from the VE table or the MAF table in open loop (i.e. without closed loop trimming from narrow band O2 sensors).

Then when you log using the wideband (which measures the actual AFR)... the wideband allows you to compare the actual AFR against the commanded AFR... the ratio of the two is the correction factor that you multiply back into the VE or MAF table.

You can either leave the wideband on the car long term, so you can periodically see how it's doing... or you can re-enable closed loop and remove the wideband.

You know you are improving your engine's performance when you get quicker ET's at the drag strip.