power enrichment

[bensalz1911]

new to tunning so bare with me,

If i were to go to power enrichment table (b0156) and let it engage earlier would you see any performance out of it. Would there be a down size to it? new to all of this thanks for the help

[joecar]

It depends what exhaust lambda is currently indicating.

Typically you can go slightly richer at peak torque (and with slightly more advanced timing, makes more torque) and then slightly lean it out as you approach peak power.

The other thing to consider is that during PE/WOT you want fueling to be sufficiently rich to protect the combustion chambers.

[joecar]

Either way, you should be mlnitoring wideband Lambda.

[Manuel]

Hi joe.

Doesn't this table make the care feel more responive, by allowing pe mode to come in earlier at the expense of economy.

Your thoughts.

[joecar]

Hi Manuel,

Yes, you want PE to enable as soon as the throttle opens significantly (e.g. opens to 35% or more, depending on a few things)(i.e. causing engine load to increase significantly).


But, it's not a matter of achieving fuel economy at the expense of of PE or throttle response; it's at the expense of the engine's ability to survive/avoid knocking (which should be #1 priority).


A different strategy is required for achieving fuel economy, like educating the driver to use less throttle.

[statesman]

There's this commonly held misconception that you tune for either power OR economy. That's total crap! You tune for both power AND economy. If you don't believe me, then try this simple experiment.... Take 6 degrees out of all your spark tables and then take your vehicle for a drive and see if there is any difference in power and also in economy. I can guarantee you that your power and economy will both take a dump. The opposite also holds true... maximizing your spark (while avoiding detonation) will maximize your power AND fuel economy.

The reason that GM sets PE the way they do is to limit torque at lower rpms. While this is somewhat detrimental to fuel economy, it has the benefit of reducing/eliminating wheel spin at launch.

[joecar]

+1 what statesman said very well, power and economy go together.

[Manuel]

Thanks. Nice work.