tuning out delay in DBW
 

I have some delay when hitting the gas at idle that is annoying and dangerous for what I do. I have logged pedal position vs. throttle position and this is not a processing lag. Throttle position follows pedal position instantly. I am using the stock tune for my 2005 SSR LS2 with minimal mods to get the engine running right. Can anyone point me in the right direction to get some crisp throttle response please? (file attached.)

Try a search.... This subject has had considerable discussion. Some recently.

I have searched and read for days and found no help. Many threads that never come to a resolution, many that do and then end before the resolution is posted, many that just trail off into history forever. I have brought threads back to the top and waited for replies and none come. If you have a specific thread in mind I would appreciate a link but at this point highly doubt there is anything here I haven't seen.

Airc...
 

There is some info over on the EFILIVE forum.
There is/was a member here, "Jim in PA", that worked on this issue...Haven't seen him in quite a while. And, U R right, many solutions don't get posted, or become "SSS", super secret shit, and are not revealed.

I have the DBW on my 55/6.0...Mine was so touchy, that I lengthened the lever arm to slow it down.
I use EFILIVE, and can get into the tun files only when hooked to the car. [The section turns red]. Those are tuneable, but are really touchy. If you get outside strict limits, the pcm can be bricked. [Or, you run over the guy in ft of you!]

here's a link to just one of many threads/posts about this:
http://forum.efilive.com/showthread....ottle+response

HTH,

Top for the weekenders ...

:Crickets:

I got a little help here:

http://www.pirate4x4.com/forum/showthread.php?t=1069897

I'm literally about to go out and do some logging now ...

So I logged some runs and the commanded throttle is so close to the actual throttle that I don't think I could humanly feel it. Thus, the lag is in the tune. (Or my TB has hardware lag, which I still need to check on.) It's dropping timing right as I hit the gas and that seems to be the obvious place to start. My stock high octane spark table had a lot of retard in it at low rpm's so I changed it all to 0-5* just to see what would happen and it still dropped timing as I hit the gas. Any idea why? I run only 93 octane, but could the computer be defaulting to the unmodified low octane table for some reason? There was no KR on any of my logs, stock timing or modified.

TR 4 is with the modified high octane spark table.

I've cured many cars with "throttle lag" without ever touching the throttle tables.

PS, just cracking the throttle more, doesn't equate to better throttle response. If you open the blade more, quicker, but the fueling and spark aren't there, you can actually make the hesitation worse. Can you say "bog"?

How??

Like any other engine. Timing and fueling. If the throttle is opening at the same rate as the pedal (and most do) then the way to make them respond more, is to make more power off idle. Timing and fuel. It's just like making a carb more responsive. You can make the throttle blades open quicker, but if it doesn't have the fuel or the spark lead, it will bog.

Any idea why changing my timing table didn't change my timing? I'm new to tuning and trying to learn so I would appreciate any help.

zero out the burst knock and see what happens

Are you referring to the max knock ret. vs. rpm vs. map table?

That's too vague of a question. I don't work well with vague.

What did you change in the timing table? Where? How much? At what point does it not make any change? Always? Was your change to the entire table? Do you have a data log? Do you have a tune to look at?

The file without the word timing at the end of the file name uses stock timing. tr3.hpl is a run with it.

The file with the word timing at the end uses modified high octane timing table. tr4.hpl is a pull with it.

I'm sorry the pulls are short but my vehicle is not street legal and I only had a short dirt field to play in without getting arrested. Regardless, the retard right when I punch the gas I THINK is the issue and they both show that.

I posted on this exact thing just a couple days ago.

You're saying that is the total timing formula?

BTW, thank you for trying to help. I've found so little help on this its sad. And for what I do with this vehicle throttle response is so important it could almost be considered a safety issue.

WOT timing is different than throttle response timing tuning. You're in a completely different area of the table.You need to use your histograms to figure out where you're at in the timing table and when, and how much timing is there (in that area) and how much it will take.

As for the total timing formula, that's pretty much it, give or take. There can be other tables in play, but those are the biggies.

I understand what you are saying but have no idea where to begin. What histograms specifically should I start with? I'm afraid that I was not logging burst retard at the time ...