raverx3m

iTrader: (1)

ive been reading alot about tuning etc from different forums and systems and have few questions that i still dont understand

1what exactly tuner does when he tunes a car?
does he increase/decrease fuel to get the engine to certain AFR?
i use this as a reference

11.5:1 RICH BEST TORQUE @ WOT this dont apply to N/A car?
12.2:1 SAFE BEST POWER @ WOT tune at WOT to get as close to this target AFR?
13.3:1 LEAN BEST TORQUE @ WOT isnt TQxRPM=HP? how can this be best torque and above best power?
14.6:1 STOCHIMETRIC AFR ( CHEMICALLY CORRECT ) tune part throttle/idle to this afr to be emission friendly
15.5:1 LEAN CRUISE for lower speed MPG(city driving?)
16.5:1 BEST FUEL ECONOMY tune to this AFR to get best MPG freeway driving
18.0:1 CARBURETED LEAN LIMIT
22.0:1 EFI LEAN LIMIT (civic VX motor?)

is this pretty much how i should make up the target AFR table for N/A motor?

why im asking? because some people show their fuel/ignition maps that are very smooth.
(or is it mostly for ITB setups)
mine was tuned and is not smooth at all. had bumps and dips. (but the power curve is relatively smooth)


if i want to run closed loop should a target AFR table be made after the car is tuned or make the table and tune the car close as you can to the target AFRs?



2ignition tables
is the spark advance also adjusted to specific air fuel mixture and RPM?

i understand the theory but cant apply it to the real world or my laptop screen

the initial spark advance is 16 degrees before TDC the spark plug ignites fuel and at 14.7afr the fuel burns at 330mm/sec and gets to maximum cylinder pressure as the piston passes TDC.
with higher RPM the fuel burns at same rate but has less time to burn so it has to be ignited earlier taking into account lower AFR and slower burn rate( more degrees advance before TDC)
what about low load/high RPM very high advance
high load/low RPM negative values


say after few upgrades the car is running lean and i increase fuel. bringing it back to 14.7 afr.since amount of fuel changed but air fuel ratio is same do i need to adjust the ignition table in that area?
or if its too rich at idle for example and i decrease fuel.

raverx3m

iTrader: (1)

and also to make sure i got this correct

after upgrading components like exhaust, intake etc(tuned car)
the lean spots on the map mean theres an improvement over old part(more air with same amount of fuel)

and rich spots mean opposite. it makes less power in that spot.

raverx3m

iTrader: (1)

bump?

mpgmike

Since you feel your power range is acceptable, let me share what I do in the normal driving range.

First, I drive the vehicle as I tune. I try to focus on one cell at a time (RPM X Load). For fuel, I lean it out just a tad and see if I lose power. If not, I lean it out a tad more. When throttle angle has to be increased to maintain power, I back off. Next, I adjust surrounding blocks closer to the adjusted block. I then move to a higher RPM and/or load and repeat. Over time, you are able to approach several of the most commonly used cells in your table.

For spark, I want the least amount of advance that delivers full power. If I removed fuel in the first stage, I will try adding advance to see if I gain more throttle response. If so, I'll add more advance. When more advance no longer makes more power, I back off to the last best setting. After adjusting timing, I can then go back and try pulling a tad more fuel. This "less fuel - more timing" routine will get you so far, but it has its limits.

This approach is rather time consuming. I usually plan on using the car as a DD for the tuning process. When I'm satisfied with the results, I remove the laptop and call it done. As far as using someone else's numbers (like the chart you listed), modified engines have their own personality. Charts only work when they reference a similarly modded engine.

One final note, disable the feedback while tuning. Look to see where the AFR is when you're happy and plug that number into the corresponding cell. As air temp changes, the feedback will keep things consistent that way.

I hope this helps.

Mike

0xenocron

If you TRULY TRULY want to understand every single one of those questions you asked...you can easily get it by taking an EFI101.

www.efi101.com

You might be able to spend HOURS reading about it on forums (sifting through bullshit to get to the real info) or spending $$$ buying books, and then again hours reading them...or you can take a 2 day trip to the next one that comes to your area and get every question and more answered.

raverx3m

iTrader: (1)

one thing i didnt ask the tunes is the AFR graph. without it i cant really tell

because after i upgraded the exhaust and changed distributor to stock my tune got messed up

now it idles at 12.0 and leans out to almost 15-16 when part throttle accelerating in certain spots.

what you mean by "Since you feel your power range is acceptable" and "disable the feedback while tuning" i no undestand

raverx3m

iTrader: (1)

which class would be best to take? what would you recommend.

i looked at the schedule didnt see any in my area or even close

mpgmike

This is where I made the assumption that your power range was acceptable. Perhaps I ***-u-me-d wrong.

The tuning program you are using should have the ability to disable closed-loop operation. If not, simply unplug the oxygen sensor to the ECU and monitor it manually with the gauge.

Have you made any attempts at tuning yet? Your successes and/or failures would be valuable to know. What else can you tell us?

Mike

raverx3m

iTrader: (1)

oh ye its been tuned open loop and was running top notch.
i had a 2.25 pipe with ITR muffler and switched to a 2.5 with vibrant muffler.

my remanufactured dizzy was already maxed out on timing at 16degrees so we couldnt adjust intake cam gear at all.

i have neptune and O2 was disabled on all the maps


im still a beginer. and been collecting information and MISinformation in the interwebs.

but its probably the worst way to go. now theres more garbage than usefull info.
i red some books available at barnes and noble. but they are mostly aimed at american muscle and boosted aplications.
i havent really found any honda specific books to read.

and i havent made any attempts at tuning.
with crome i pretty much spent about 80% of time trying to get it to do what i wanted.
and trying to calibrate/setup/ fix/reinstall drivers/ reset units reinstall reprogram etc.

with neptune i actually spent few hours setting it up and rest learning how to use it.

most i did is drive around collect some datalogs. and try to adjust fuel tables in small areas.

i copied my crome tune tables into neptune and adjusted the rpm/Mbar scalars to match. set the new injector size to 480cc according to the injector test info found on one of the forums.
now the idle is even more rich(11.2) and theres a big lean part throttle area that goes to 16.6 when accelerating.

car idles at 900rpm/299mbar table
when i try to decrease fuel the numbers almost cross the column before it.

so i dont know if i should adjust the numbers or change the Mbar value to match it better.


i also dont want to adjust too much where i dont understand what im really doing so i adjust and if it dont feel right i load the stock map on it again.
because i dont know how other settings relate to everything yet so im just messing with small areas on teh fuel maps while im driving to and from work i datalog.
the maps side by side(original crome tune)
imported in neptune.

mpgmike

On that second table it looks like your X-axis scale starts at 45 then jumps to 213, then 299. You need much more resolution at that lower end. Try rescaling the X-axis to get a bit more in the low end of that scale. That could explain why you go from 11:1 to 16:1 with a slight tap of the throttle.

Mike

raverx3m

iTrader: (1)

oh sorry posted the wrong maps

i do have them rescaled very close to crome maps above.. this was just saved before i did.

raverx3m

iTrader: (1)

also heres the target AFR table i made up the best i could

when car was tuned it was at 12.5 WOT and 14.7 at idle/light cruise

98vtec

research speed density and how it works. tuning by small portions of the map one by one will take forever and youll never get anywhere taking each cells afr number to heart. just because the selected cells are highlighted during a trace, that doesnt mean the ecu is using solely those cells in its algorithm for fueling. it can be using surrounding cells. with that said, if the highlighted portion is lean, there is a good chance a surrounding cell block could be lean and cause the lean condition.

also, dont import crome files to neptune. its different. look at the map scalars and rpm. they are different.

put it this way, if you had to run down, physically, the 2d lines, would you rather them be smooth or would you rather them be peaky? im sure the injector likes a smooth graph for smooth transitions to different loads and rpm ranges.

remember if you have the logger to display everything from idle to wot in the lambda chart, you will see throttle tip in and tip out plotted. dont let them distract you.

raverx3m

iTrader: (1)

i know they are interpolated. it idles at roughly 300mbar which is inbetween 2 columns

what i meant is i adjust one block at a time but i adjust whole area so the 2d maps look smooth
what i was asking is.if i have to lower the fuel values so much that they are lower than the cell next to it(the graph crosses lower line)
is the proper way to decrease the mbar column value so the whole line moves down?


i watch the graph also to see how the cell changes look on the 2d map and adjust the neighbor cells accordingly so there is no sudden jumps in the fuel.

the problem is. with the timing that is set (16.5 for idle)
when i get the car to 14.7afr at idle i dont like how the engine sounds.
at about 12.5-13.5afr the engine sounds smooth. but at 14.7 it starts to sound rough.
not by much but audible difference.
yesterday once i got it to 14.7 i tried to adjust timing between 15-17 and didnt notice any difference.

raverx3m

iTrader: (1)

heres what i have to do to get it to in order to idle at 14.7

the selected green dots

98vtec

when you first did this map and started initial tuning for idle, did you set main fueling compensation first or did you immediately move to the fuel table?

raverx3m

iTrader: (1)

new injector size is set to 460.
according to this chart i think its safe to assume that most of the rdx injectors flow similar values.


overall fuel trim is at 0
other values are same as stock gsr basemap

GagnarTheUnruly

iTrader: (3)

Someone please correct me if I'm wrong, but shouldn't the target AFRs be stoichiometric until 700 mbar or so? Seems like his target map richens up very early. Or am I totally off-base?

raverx3m

iTrader: (1)

it depends where you look. even the"generic"tables are all different

0xenocron

Target AFR tables DO NOTHING in Honda ECUs...they are they if you plan to use the built in math functions in the ECU, auto tune, etc...but the ECU itself does not use they AT ALL like they would in an actual VE Based tuning system.

0xenocron

I know Kaizenspeed has had a few of them there, they may have more I would assume as interest gains.

Definitely the first class to take is the 101 class. Take it, let it sink in, practice the principles it teaches you and then maybe come back for the advanced class a few months to a year later is my recommendation.

98vtec

using main/overall fuel first calibrates the map to your engine which makes the tuning process easier. as well as prior to starting, setting up injector latency and sizing.

GagnarTheUnruly

iTrader: (3)

But for street tuning they can be useful because you can set a target and then see whether you are running rich or lean relative to the target, without having to remember your target for each cell. Based on that what do you recommend for part throttle? A target map like the one that was posted or one that stays at 14.7-15 from full vacuum to 700 or so mbar? Or something else?

0xenocron

Well, I guess the more you do this(especially on a dyno) live and not from logs...then you are doing that on your own as a tuner. I suggest people get practice at doing that "difference %" in their head quickly on the fly, rather than relying on the computer until you get good at doing in your own mind. I work faster that way, its my preference...but every has their own.

As far as the target tables, it really depends on the setup...Turbo or NA, high comp vs low comp, the supporting mods, the purpose of the vehicle, the goals for driveability, gas mileage, etc....

On a standard street car that isnt prone to any knock or issues, Ill target 15.0-15.3 up to about 500mbar, and 14.7 up to 800mbar and then above that depends again.

On a road race car, I will try to keep everything in the 13.3 range for power and transitional reasons.

On a drag car, who cares! lol

GagnarTheUnruly

iTrader: (3)

^^ Awesome info, thanks!