Hello,
Hope all well.
I would like to increase my engine braking as trying to fine tune.
I have efilive and understand may be the throttle follower cracker tables

When if accelerating and i come off throttle i want to increase that braking a bit more as having to brake harder at the moment but dont want severe engine braking if shifting up through gears, so is this the delay?
What exactly should i try?
would like a bit more less cruise control in all speeds but more braking at higher speeds after a delay.
Have attached my latest tune COS3
Regards
gavin

 

Hi,
increase values in follower decay rate?
regards
gav

 

Since you want more engine braking in one case, but less in another case (shifting), you need to wonder about two things:
How can the PCM "know" the difference between those two cases?
What mechanisms exist in the PCM that might be tuned differently get the two behaviors that you want?

It would help the rest of to know which PCM you're working. I'm only familiar with the P01 and P59, hopefully this has some relevance to you.

First of all, make sure rolling idle is disabled. That feature holds the throttle open when you want it closed.

Both throttle cracker and throttle follower affect the rate at which the throttle blade closes, and both of them have a "decay rate" (how quickly the throttle blade closes) and "decay delay" (how much time elapses before the decay begins).

I'll admit up front that I haven't tried this, I'm just speculating...

There are "neutral" and "in gear" versions of the cracker and follower tables. I think the "neutral" tables are active when the clutch is pressed. If that's accurate, you could give that a long delay and slow decay to have mild engine braking when shifting, and you could give the "in gear" tables zero delay and rapid decay to get more engine braking when not shifting.

If I'm wrong about the "neutral" thing, you might be able to get the effect you want by giving them a long enough decay delay to hold the throttle open for shifting, and give them a fast decay rate so that after the shift the throttle closes quickly.

Then there's the question of what throttle opening you end up with after the cracker and follower have decayed. As far as I know the only adjustment you have for this is the desired airflow table, and that needs to be set to whatever airflow is needed to maintain idle. That table has "in gear" and "neutral" columns so you could play games with that too, but when you lift the clutch you're going to have to give it some throttle to prevent the engine from stalling.

You might also be able to get some benefit by disabling idle mode above a certain vehicle speed. I haven't played with this at all, but I wonder... if you disable idle mode above 25mph would that completely close the throttle and give more aggressive engine braking? If it does, it would probably also make the engine stall if you hold the clutch down for too long above 25 mph. But it something you might want to experiment with.

 

Hi,
thanks for reply, will look through some of those tables, however my swap doesnt have a clutch switch wired to LS1B 0411 PCM.
regards
gav

 

I know when mine goes into dfco it really has some engine breaking. Those can be manipulated pretty easy.

 

Hi,

How u got your Dfco set up?
Can i still autove tune with it enabled?
last thing i want with my car is any popping banging etc though
regards
gav

 

popping and banging can easily be tuned out. just set up your dfco activation to be aggressive. also, if im remembering right, it wont cut fuel until the timing has fully decayed in or out, so those settings need to be adjusted also. either make the timing higher or increase the decay rate.
for the autove stuff, you just need to get your filtering right before applying the correction factors.

 

HI,
Just a question.
In table B4317 for throttle follower how does it know which gear i am in if i am M6?
It only shows 4 gears as well and only goes up to 132 km/hr so what happens after this speed?
Regards
Gav

 

I could be entirely wrong, but since it's a manual, I'd guess it only needs to know if the clutch is on/off, otherwise it's probably just going to follow the throttle. I've never dove into a manual setup for that.

 

Hi,
i added 50% to all those values shown and its a little better.
Need to do same again and then do some driving.
DFCO isnt enabled yet though. Got a feeling if i did enable it those follower settings may affect it too much.?.
I dont have aclutch switch wired in on my swap.
Merry christmas to you all anyway.
regards
gav