Is there a way to control spark by MAP rather than airmass?

[cc-rider]

Does anyone know of a way to control spark by MAP? I'm wondering if there is a way to take a few degrees of spark out as my supercharger goes through the transition into boost. I get some KR with hard transitions into boost that I don't get when I get into boost a little bit slower. Its always hard to tell if I've truly got spark too high in some regions of the table, or if the massive shot of pressure that PD superchargers have is causing the KR.

The only tables I found in the spark section that have MAP are shown in the attached picture. Could I populate the Gas AFR correction tables to be -3 (to pull 3 degrees of timing), and then use the mult table to enable it by MAP? Its still not an ideal solution because that mult table only goes to 100 kpa and not into boost. But it may allow me to pull some timing as it transitions through the 70-100 kpa region which may effectively work.

Anyone ever played around with this?
Are there some other tables I'm not seeing that allow spark control by MAP?

1 hpt.jpg

[cc-rider]

Nevermind. Right after I posted this I decided to add airmass to my log and see if it follows MAP. Its a damn near perfect 1:1 relationship between airmass and MAP. So the standard airmass table can do exactly what I'm thinking.

I showed my rookie stripes with this thread. Still learning...but getting better every day

[10_SS]

Nevermind. Right after I posted this I decided to add airmass to my log and see if it follows MAP. Its a damn near perfect 1:1 relationship between airmass and MAP. So the standard airmass table can do exactly what I'm thinking.

I showed my rookie stripes with this thread. Still learning...but getting better every day

Airmass is calc using MAP in Speed Density, right? But, you can use Burst Knock to pull timing in transition... I added Burst Knock duration and intensity to mine instead of reducing it like people love too due to blower on stock LS3 compression and pistons.

[cc-rider]

Mine has burst knock disabled. Even the stock KB tune has this disabled. And I read here where zeroing out the prediction coeffiicents and burst knock is a good idea because we really don't have all the tables we need to control them. Not sure if that's right. I'll try to study up on burst knock.

[FunkedOut]

My stock tune has burst knock enabled. I can see it activate when I log about when you're looking to pull timing.
I'm NA, but it comes on when I stand on it from 20-30%.

[cc-rider]

What exactly is burst knock. I know I'm being lazy and not searching and reading up on it. Don't have time tonight. But if anyone can steer me to a good thread to read or give me an overview here I sure would appreciate it.

[10_SS]

What exactly is burst knock. I know I'm being lazy and not searching and reading up on it. Don't have time tonight. But if anyone can steer me to a good thread to read or give me an overview here I sure would appreciate it.

its automatic timing retard to stop knock from occurring when you mash the gas, last for milliseconds just to handle the transient. Without it, and stock high compression, you will have knock at tip in/pedal mash. Add boost to the equation, then you see more of it. the logs I posted in the Transient 3999rpm limit, I have it logged on there. Without it, I get real knock on tip in.

I would really just put it back to stock. But, if your in just Speed Density mode, then you will prob have to adjust it, since when I went pure SD mode, Burst Knock was going crazy. There may be no perfect way to use Burst Knock in SD mode on this E38 though.. not sure... I didnt play with the settings, I just disabled it for tuning SD tables then went back to MAF mode, and re-enabled Burst Knock.