raverx3m

iTrader: (1)

so when my car was tuned i watched what my tuner did kinda

he would build the cells column by column and then i didnt see what he adjusted after.


i assumed that he built a single column at a tine on the dyno at each mbar reading and then adjusted fuel in that column and run again to see the changes.

and then move on to the next column and do the same. and after that adjust the ignition timing.

is that how its done?

im a bit confused since the ecu reads 4 cells at a time and interpolates the values.

do i have to start tuning from the lower columns( more vacuum) and move up WOT or it doesnt matter.

because what ive been doing seems to give me pretty flimsy results


when i drive around i fill in as much of the tables as i can and then pull over and adjust the whole table at once in small increments. and then i have lean/rich spots moving around the tables and it takes forever to get it somewhat close

whats the correct way of doing it?

raverx3m

iTrader: (1)

anyone?

odz-fab

are you in open or closed loop? the dyno is really the best way to control steady conditions to accuratly do it. im all about learning and diy but i wouldnt risk my engine.

wide band?
egt?
tunning software?


and exactly as you said.. it interpolates.. it can get tricky. trying to hold an average between 250-500 rpm change and load readings takes alot of comprehension and experiance. id read more into fi tunning books and get a better idea of the bigger picture.

its not a dirrect answer to your question. but it seems that you need more knowledge about the entire tunning theory.

show someone how to load a bullet but doesnt know the consequence of wher ther point the gun or what pulling the trigger will do is very dangerous.

simply saying take cuation

raverx3m

iTrader: (1)

its open loop
that's why im learning.
ive been reading articles and books and some of them are not exactly correct for Honda tuning lol.

but I watched my tuner do it and it seems like its much easier to set it row by row from the bottom up since it interpolates.

last time I managed to tune the car somewhat close just cant get it stable afrs


I just need to find a road that I can do stable acceleration for each cell without traffic( lol if that's possible)
Neptune wideband no egt.

car was already tuned but with wrong injector offsets. so im just adjusting it for correct offsets

scmil95eg

1. Your fuel table should be relatively smooth and linear, there shouldn't be any drastic steps from cell to adjacent cell
2. Management systems use a weighted interpolation strategy, so if you're 60% in one cell and 40% in the next, it's going to deliver the sum of those two cells (or three, or four)

So if your map is accurate, interpolating between two (or three or four) cells shouldn't throw off your AFR. If you have walls of fuel between cells, I'd expect your car to run like crap with AFR's darting all over the place. Graph views are good for spotting these drastic variations.

On a completely unknown combo., I'll limit RPM and load to a level I'm confortable with and tune up to the limiter. Keeping RPM the same, I'll increase the load limiter step by step until I'm atmospheric or at max. boost. When I'm happy with everything up to 3000 rpm and max. load (for example), bump the rev limit up to 4000 and bring the load limiter back down to a level I'm confident with (mostly on boosted engines). Once you have 3 or 4 columns mapped out you should start to see a trend for that engine and what it's going to want. How you actually "do it" depends on how thorough you want to be and how much time you have to spend. After 7 years and 130,000+ miles, I still make adjustments to my car. You could spend a lifetime playing with any one engine combo. if you wanted.

blackeg

I think u know the answer. Find a road with no traffic so you can hold it steady for a few seconds. Enough time to see the wideband, see what cells its using and highlight and change them accordingly. Then u can get into the throttle back to those cells and see how the changes worked. I usually do this and it can throw down a pretty smooth streeet tune. Ill do this for all the colums except for the last 2 or 3 on the right the high load ones. For those I record the datalog and just keep an eye on the wb make sure it doesn't go crazy lean or rich, then make changes later when im looking through the logs

odz-fab

if you have s300 or ecu with a datalog switch, do a set of pulls of cruising or freeway acceleration and datalog the lean points for a just a sec. look at the rpms in wich you see that spot. check your datalog and crossreferance the rpms vs the load colums you were dataloging to help pinpoint the problem areas

egb18c5

raver, i feel your pain. i'm sort of in the same boat as you but only when it comes to a "smooth" road. in reality, life would be much easier on a FLAT road as you can keep the loads consistent and try to adjust it cell by cell rather than a group.

scmil (whats up scott! sent you a pm awhile ago lol) says it best, monitor the graph and keep everything smooth.

someone correct me if i'm wrong but regardless of the engine, you give the engine what it wants, doesn't matter if its a honda or not. some engines have way smaller windows so keep an eye, or an ear for that matter, on it.