Something I have been experimenting with recently is scaling the ROM so the parameters we are likely to use the most have maximum tunability at the slight sacrifice of other areas. Most of this only has application (in this instance) to cars that spend time above 6K such as at the track or at the dragstrip. The inverse of this is that cars that spend most of their time 6K and below, like rally cars, can benefit as well. I am not fully aware if the Evo meets PGT rules, but that aside it could be done for a rally team on something of a budget. I have been using my car as a test bed and even on the street the rescale (in 250rpm increments where possible) works great.

Basic theory is make the ECU interpolate low rpm, no or low boost cells, as much as possible and give the extra depth to the areas where you need it most. I was going to post some maps showing this done, but until I have it 99% foolproof I am going to hold off.

Anyone else doing something similar or messed around with this?

 

I have wanted to try this but I have not had the chance. I noticed the need for it most when I am tunning my fuel map. It would very helpful to have additional resolution especially for load between 220 and 320. Do you notice any draw backs in term of daily driving with lower loads?

I saw on the other forum that you really added A LOT of resolution to the RPMs above 5k. In what way specifically have you found this to be helpful? Maybe its becuase I'm only on stock turbo but I have never really felt the need for that much resolution at such high RPM's.

 

See thats another area that I havent really gotten into, but you can definitely increase the resolution in the load axis as well by eliminating alot of the redundant lower cells below 100%.

Daily driving hasnt been adversely affected and I feel it may have been improved somewhat.

The reason I think this resolution is needed (especially at the drag strip or road course) is I noticed that taking 1* out can cure alot of knock situations up to 5 counts (as have others). But I thought about it this way, why take out 1* from 6000-6499 if all I really needed was 6000-6249 and I can add 2* from 6250-6499? At the track I never am below 6K while racing and there you can afford some driveability problems since you are only on the return road for a short while and at idle the rest of the time.

I have a few versions of that map you mention that are even crazier (course its all around craziness, not just one particular map).

 

That is a good thought about not reducing timing in areas that don't need it.

I think I may scale my maps for more resolution at higher RPM and Load, probably not as drastically as what you have done but I might try it a bit to see how it helps.

I prefer to have one map for track and street and would not want to have a high resolution map for the track only, maybe I can find a happy medium.

 

i just assumed people were doing this already. to give better resolution in trouble areas right around peak torque or peak boost etc. when you see how redundant the lower load cells are, it just seemed like common sense - to give more resolution to the more important areas.

 

I have rescaled slightly but JB is talking about a much more radical rescale where you have much higher resolution in RPM's above 5k

 

certainly for 8's and below you could re-map the axis's+map's rather than rescaling it, so you dont loose any load/rpm cells but gain others.

its harder to do for the 9's because of the shear number of maps that need to be re-mapped...

 

THIS AN EXAMPLE AND HASNT BEEN TESTED

However less radical versions of this have been tested and work okay for me. Any damage that may result from usage of a similar format, not fully understanding what this implies, etc. is completely on the end user and I will be liable in no way or form. This would be an example of a RACE ONLY map like I had been talking about before. As Dudical can attest to the "street" version is a little more practical and not quite so severe in execution.


that being said:



Would you actually need this much resolution? Well maybe but its highly unlikely unless the ROM was speed density or a blow through and needed the extra help to take advantage of what was there.

 

David, how big can you make a map for an 8? The IX is 20x21 is 24x24 possible? What are the limitations?

 

Its crazy to see that table and think that you spend most of your time in the top left 16 boxes.

 

JB,

As big as you want - the limitation is finding contiguous free space in the ROM. Which for the 8 ROM is kinda hard haha

I just too a look at the 11 ROM and there is about 1000 bytes free right at the end - honestly I thought there was more free space in the 8 ROM, apparently not

 

I think a 24x24 would be awesome as it would add another 4 axis points on the rpm to add back the 500 rpm increments, and another 3 on the load which would add some of the 0-200 back.

I really need to learn to code, can I DL yourbrain.hex and flash mine? I promise I wont redistribute it

 

fuel and timing?

i suppose it could be done - hopefully you could reuse some of the existing space (if they have back to back low/high timing/fuel maps)

edit - high fuel and low fuel are back to back so you could reuse that segment and remap lowfuel someplace else!

edit2 - high timing and low timing are also back to back ...

edit3 - so yep you could go 24x24 for fuel and timing - it would be a squeeze but I think it would be possible on the 8's... 9's are no problem because there is bucketloads of ROM space, its just the complexity of 6 timing maps...

 

tephra,

I can see this as being another wanted patch.

Increasing the number of x,y cells in the fuel/timing maps would be great so that rescaling wouldn't be necessary. If the high/low are back to back like you mentioned, would that basically mean that you could double the size of the high maps and then relocate the low maps to unused space and make them the same doubled size?

That would be pretty cool and I think a lot of people would pay for that as well as your other great patches.


Eric

 

could be - lol why do I make work for myself :P

if we could agree on how many extra load/rpm points everyone would like then I could do up some dummy ROM's (like the knockcel patch)