What does slow/fast accel/deaccel affect?

[MWPau]

Hi all,

So as the subject says... exactly what does slow/fast accel/deaccel affect?

I understand how the other engine states determine some of the other MS3 actions (idle, etc), but not the one i mentioned.

Thanks.

[jsmcortina]

I noted in the manual
http://www.msextra.com/doc/pdf/html/Meg ... .5-89.html
what each state effects.

James

[MWPau]

Yup, you say what its used by... but not how it affects those controls.

For example:
"Fast deceleration threshold:
Used for overrun fuel-cut.trol, idle-VE and idle-advance, idle-VE, idle-advance and overrun fuel-cut."

(youve got a few typos in there too).

[jsmcortina]

OK, I have a table drawn up that shows what "States" the affect and what those are used by. I didn't include it in the manual to keep things simpler.

Basically:
- you need to be in "Idle" state plus any additional conditions before any of the idle stuff will trigger.
- you need to be in "overrun" state plus any additional conditions before overrun will trigger.

James

[MWPau]

It would be great to see that table if possible.

At the moment my slow and fast accel rates seem rather flakey on the log. Almost as if they need some amount of hysteresis.
The problem is since i dont know what they really effect, i dont know if they are actually set correctly or not.

[whittlebeast]

One system I tune adds a fixed percentage fuel on hard accel.

http://www.nbs-stl.com/MLVDemo/800%20Mo ... d%20PW.png

Andy

[Dennis_Zx7r]

Regarding slow accel, the manual states:

When RPMdot is more negative than this value (larger), your engine is decelerating. To set this, cruise in a high gear, then see what RPMdot value you get by lifting off the throttle fully and decelerating. Set this value slightly above that RPMdot value.

First, what does "above" mean in this context? More negative, less negative?
Second, I think setting the value this way would cause my engine to detect decelaration while in idle. RPMdot is up to -300 in idle while it's only -100 to -200, depending on the RPM when the throttle is initially closed. Should this still be set according to the description in the manual?