acceleration enrichment

[dave smith]

can someone please tell me where in the software on s8(scal) is the acceleration enricment (mine is a bit woolly as i open the throttle.) ive looked but im not sure which table it is.

[secure]

Not sure for the S8 but for the S6
Run-Mode Fueling > Corrections > Transient Fueling > Positives for Acceleration enrichments negative for de-Acceleration enrichments

It should be the same for the S8

[pavlo]

Doesn't sound like an enrichment problem, although it could be too much causing it to go "wooly". The enrichement really only comes into play on quite fast throttle opening at lower airflow rates where the relative changes in airflow are highest.

What does the engine do if you snap the throttle open to at least 50% from near idle?

First of all you need to look at the lambda on snapping open the throttle. Log or at least watch fuelAddTfc1 and see what it's doing.

I would suspect though that it's the fuel map, it's not unusual to have the fuel map not actually tested at say 1500-2000rpm at atmospheric pressure.

[dave smith]

thanks guys sorted it was the transient fueling. the map was fine just when you snap the throttle was flatish,

[pavlo]

You should still probably see what the fuel does if you load the car up with some throttle in a high gear at 12-1500rpm, it's an often overlooked part of the map. Trying to get the transients sorted can be a pain, if you have a lambda sensor close to the cylinder head then you can look for the lean spike on throttle activity, but it's often hard to stop a subsequent rich dip. Watching the exhaust is a good shout too as you can spot the black puffs of smoke that come with a little too much fuel.

If you were a long way out then I would also seek to confirm your injector lag times as they can have a large effect when combined with other corrections, especially if you're using large injectors with generally low opening times.

[dave smith]

its actually on a turbo hayabusa drag bike running e85 which idles at 1600rpm it was just a little flat spot at fast throttle openings WOT is really all i use but its nice not to have a flat spot.

[pavlo]

Lol, yes with something that fast revving it will be enrichment! Especially with E85 as your enrichment values will need be higher in the same way the base fuel is.