No negative timing numbers from Create Boost Table wizard

[silum]

I have noticed a bug/feature in the Create Boost Tables wizard regarding timing. It won't set any cells to a negative number. So if the last non-boost cell is a negative number (ex. -4.00) and your settings for the wizard should produce a slightly larger but still negative number (ex. -2.25) the wizard just ouputs a zero for that cell. It's not a super big deal but it's nice to now that it behaves this way.

I have found a little work around. You can adjust your base timing up, say 10 degrees, run the wizard then set the base timing back the way it was. This will give you negative numbers.


-Dan

[G3-TEG]

I don't believe that is correct.. You DO NOT want to have negative numbers in the timing table. I believe the negative numbers you see are bugs in the conversion when the table is created.

The timing values there are TOTAL ADVANCE values. Thus for example, if you are running 25deg total advance at WOT at 0psi, and you want to lower the timing by 4 degs at 7psi, then you should set the timing to 21degs.

You should never have a value of 0 or lower in the timing table.. it just doesn't make any sense if you think about it. Thats why you can't enter negative values.

HTH.

[silum]

You can manualy enter negative numbers. The values are not absolute. They are relative. So setting your base timing setting in ROMEditor to a very low number will not change the timing. It will reduce the displayed value by the same amount. Does that then make all of the negative numbered cells invalid?

I've already talked to Hondata about this months ago. They acknowledged what I've said and believe that it's not really a big deal because the engine is hardly ever operating in an area of the table that generally has such low or negative numbers. I just wanted to post the info so others would understand the operation of the table wizard.

[pissedoffsol]

The timing values there are TOTAL ADVANCE values. Thus for example, if you are running 25deg total advance at WOT at 0psi, and you want to lower the timing by 4 degs at 7psi, then you should set the timing to 21degs.

Can you explain this? I don't follow the reasoning behind it, and would like to know what negative values do for you/take away from you.

Thanks

[silum]

The following uses a P28 as an example.
To make it simpler I'll make colum 10 = 0 psi and B13 = 12 psi.



OK, Lets say we have a cell in one of the timing tables. And lets say that this cell is located at XXX RPM and in colum 10 (wich is close to 0 psi relative to atmosphere). If the value of the cell is 5.25 and I want the boost wizard to retard timing 1.25 degrees per pound of boost then I should get -9.75 degrees of timing when the engine is runing at 12 psi ((5.25-(1.25*12)) = -9.75). But you won't. It will make B13 and every cell after it read zero.

So anything above 12 psi will not continue to be retarded more than the previous cell.

My argument is that if you graphed one row of the timing values under boost you should get a downward sloping line that continues below zero rather than a downward sloping line that hits zero then levels off.

All of this is just an example of how the wizard works.

[G3-TEG]

Your right.. but the problem here is that you would never be running 5.25 degrees TOTAL ADVANCE from say 4000rpm to redline at WOT in column 10.

Even at close to redline, your total advance at 0psi should be at pretty much stock values which range from 27.50-33.00ish degrees. Thus even if you pulled 2 degrees of timing per psi, at column B13 you'd still be in the positive timing values.

[silum]

Yes. It really doesn't affect anything since most people don't run 12 psi at 1000 RPM.

I was just bringing it's behaviour to others attention.

[Hondata]

This has been fixed in RomEditor V3