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Discussion Starter · #1 ·
Sup guys,

Spent sunday dialing in my roomates car, figured Id share where im at, and some of my processes, theories, etc on tuning.

The setup is a built Z6 (eagle rods, SRP pistons, etc) in a 96 Civic DX, getting ready for turbo (basically a modified greddy kit). Car ran into a financial speedbump, it was slated to get done last august, but now that the funds are back things are going full tilt. Its got DSM 450s, lc1 for wideband love, GM 3 Bar for boost reading pleasure.

We were lucky enough last year to have the mad scientist in town to help with the wiring.


so we know the wiring is straight hehe.

So i whipped up a sick z6 basemap, made a few calibrations to it, disabled things like ELD, o2 sensor. set a sane vtec crossover point (well find the perfect one on the dyno) Locked the base timing, timed the beast. Scaled the fuel enrichment till the car idled solid and took it for a spin to blow out the dust bunnies. Car started off pretty good, rich almost everywhere. I setup some target AFRs in the 350-800mbar range. I tune the idle by hand, and the WOT runs, but I let neptune work some magic on the section formally known as closed loop. Then I go in an smooth the tables. I also give the timing tables a once over and make sure they look good to me. a stock z6 will want like 26-28 degrees of TABLE timing up top at least. The key here is getting everything smooth, and dialed in so I can expand out the scalars past 1000mbar and make a good boost basemap to start from.

So we do some driving, I get everything dialed in nice. Then I added like 10 percent fuel to the 850mbar-1000mbar load columns, and we go for a few 3rd gear pulls. Of course the pulls are plenty rich, which is a ok. I keep scaling them down until we are getting nice numbers (all the while making sure we stay in the 0 percent correction section of the ECT and IAT maps, if you have to, dial them out for tuning, you dont want them screwing with your logs until much much later). Swapped in a fresh set of plugs on the side of the road, fire her up, did a nice pull, shut it down, coasted off the road, pulled the plugs and there was no signs of detonation (which there shouldnt be, haha, its an na z6 with only 28 degrees of timing!)

Now, you can see how the fueling is easy, because you have constant feedback. Timing is a whole nother animal. I only know what the timing should be from experience, and from the stock maps. I pull the plugs to look for obvious detonation, but I really should make some detcans.

Anyway, that was kind of a brain dump, but next up Ill show you how I take a solid non boost map and turn it into a great starting point for boosted, and why this is hard on hondas (it has to do with the legendary xxx psi on this turbo doesnt equal xxx psi on that turbo thread).

Here is one of the last couple of logs I have. You can see im still a little rich up top here, I ended up dialing that back. but its all about smoothness. Heres the pics, Ill talk about each graph in a second. I dont log manifold pressure here, well, because its 1000mbar give or take haha, its NA. once its boosted Ill be logging it for sure.




The first graph shows throttle position, so you know its a WOT run. It also shows RPM, for reference.

The second graph shows you table timing, and ACTUAL timing. There is a hidden (or not so hidden depending) table in honda ecus that adds timing on an increasing scale as rpm goes up. with Neptune you can choose to use this or not. I tend to use the stock adjustment in the NA section of the map, but switch to straight table timing in boost. This makes boost tuning much easier, but keeps all your normal driveablilty. Its good to note that 28 degrees of timing is actually almost 35 at 6800 rpm :shock:

The last graph shows AFR and duty cycle. The duty cycle is nice and low (27 percent peak and that was running rich) so plenty of headroom for BOOST!. The one thing Id love to add is a logged fuel pressure. On my car Im going to do this with an electronic fuel pressure sender and wire it into one of the spare inputs so I can log it. It'd be great to know the fuel pressure is dead nuts solid.

You can see, my AFR transition on that pull is nice and smooth. Since then Ive worked out those little kinks. Both your timing and fuel maps need to be smooooooth. No jumps, spikes, plateaus. Right now the car is running mid low 13:1 all through its real power band. This will be great for scaling out to boost tables.

I think thats it for now, Ive got some work to do here at work, but I thought some people may be interested in seeing this.

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Nice little write up. Too bad I dont know what all youre talkin about.

I dont know if you remember but I posted something about tuning a while back and I really want to learn how to do it. Is there like a website or somewhere that help teach you how to do it?

I have been searching online for something and Ive found plenty of places that will sell me the stuff to do it but nowhere that really tells you how to use it.

Im really considering just getting my car tuned so I can sit next to the guy and be like "whats that?" "why are you doin that?" "how do we fix that?"
 

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Discussion Starter · #3 ·
all ive learned ive learned from picking up things around the net, general tunign theory, my EFI 101 course, school, and experience.

its hard to like sit down and explain everything, if you can latch onto someonw who knows how to tune cars that always helps.

really htough, its all very dynamic. tuning my WRX is alot different then thuning my crx, but its alot of the same theories. if you have any specific questions I can do my best to answer them.

if you are simply talkinga bout tuning your own car, my number one suggestion is to get a really good system like neptune right off the bat, itll maek y our life so much easier.

I previously tuned this car on crome and it runs better now, with a fraction of the time and effort.

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Excellent post! Of course we all have our different ways of doing things but this is very informative, I'm gonna add it to the Modification FAQ.

I definitely agree on the system, I honestly would prefer to never tune a car on Crome again. As a beginner, you'll constantly be battling with not knowing the shortcuts, connection issues, and all that extra crap that takes away from the tuning.

What Matt is saying about the xx psi on whatever turbo has to do with airflow, and this is a great way to illustrate it. Say he tunes this engine on a small T25 that makes 200whp around 12 psi of boost. Then Jay decides he wants to make more power, and slaps on a GT35R. Now all of a sudden hes deep into the 300s on that same 12psi, what happens to the map? The engine now is only getting enough fuel for about 60% of the air it's getting, runs lean and then you have problems. On a MAF car, this isn't so much of an issue because the sensors read air mass directly. This is why it's ESSENTIAL to get a new tune when you change things with your setup.

zelfear, please do not do that to your tuner unless it's a friend, or they make it explicitly clear that it's ok. I know a lot of people are secretive about stuff, and some just plain don't want to be bothered while they are trying to tune a car, especially on the dyno making pulls that are very hard on the car. Once I get the maps straight on a street tune when I'm driving with the owner of the car, I try to explain as much as I can, if they care to hear it. I've defintiely had people asking me a million questions and it bothered me.
 

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Discussion Starter · #6 ·
in addition to what tom said, youll also have way too much timing.

see, on a MAF based car (lets call it a WRX), you have a table like this for timing (this is very simplified, but itll get you teh right idea)


and a table like this for fuel


Its a table of load (in airflow) vs rpm. So like, on my 13T @ 16psi I can hit like 2.4 g/s, i fi swapped on a differnt turbo, like say a 16G @ 10 psi, and it his 2.4 g/s it would still be pretty close to being right. Pretty much the same with the fuel.

now on a map based car like ours you have maps like this



thats rpm vs manifold pressure. these are very very tied to the exact turbo setup you are runnning, like tom said. 12 degrees of timing is enough retard (hopefully) for 20psi on my roomates 15G (300hp turbo), but if i went down to the basement and slapped on the GT3076R (500hp turbo) his car would be broken in no time flat.

On a big, high airflowing turbo like that, youd need to pull more timing sooner, and youd have to add in significantly more fuel at lower boost.

can you see how a MAF car wouldnt have that problem? if it flowed more air youd simply be in a higher load column and be scaled semi appropriately.

if anyone has any specific questions or comments lmk.

also, tom brought up a good point in a conversation last night. back at the beginning where I was showing duty cycle, you have to remmeber that is just a best guesstimate, adn I was using it mainly to show that at a constant AFR, duty cycle increases as rpm goes up. You cant really use duty cycle (on our cars) to determine if you are runing out of injector flow or not, even though the neptune estimate is pretty good. If y ou use crome, never even look at it, itll scare you when its like 150 percent haha.

also, disclaimer, im not resposnible for anything you do wiht this information haha

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Well I guess I will just keep doin research. I dont know how but I completely forgot about Pgmfi.org. Ive been on there before but that was when I was finding out about chrome and neptune.

Dont worry Dowest if I were to do that Id make a special trip to the FL to bother you. JK.

If I do end up giving up on tuning and fianlly get my LS/Vtec together (hurry up with that head jk) then I prolly will bring it to you to tune it.
 

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Discussion Starter · #8 ·
we continued on with the turbonics last night. soon ill be able to acually tune this thing and it will move. hehe. pictures!








mmmm mmm turbo goodness.

did some more tuning on the WRX to get the feul economy up. heres a pic of goof cruising fuel economy


and a picture of bad passing some people fuel economy, sorry for the blurry shot!


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so how exactly do you change the a/f ratio? like, what functions do you have to enter? or is it just like @ 3k rpm a/f ratio = 14.7:1 (isn't that the stoichiometric or chemically ideal mix?)
 

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Discussion Starter · #10 ·
well, on an open loop map (like when the ecu is straight up controlling your fueling based on map values) what it does is vary the injector pulse (usually in ms). as you can see above in the WRX tables the fuel values are represented as AFR, but they arent super accurate, they are just an estimate. the honda numbers you just see numbers. increase the number, you increase the fuel.

the tables are all rpm vs load, so 3k rpm actually has a whole lot of fuel values depending gon your current load.

14.7 is stoich yes, and its good for emissions and thats about it. at light load you want to be leaner for good fuel economy and at high load you need fuel to keep your car from assploding.

Ill snag a shot of my target AFR map in neptune and post it up, maybe that will help.

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how exactly did you "whip up" a basemap in neptune? did you download the stock map and edit it from there? or is there a way to start from scratch and set a max manifold pressure on the map and max rev?
 

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Great thread guys. Glad to see others think that a smoother map make a happier car.

I know of at least one local tuner that thinks I am nuts for trying to smooth out y fuel map and timing maps.

Great point about the speed density(Hondas), and mass air systems. It really does make things trickier on a speed density setup, but not too terrible IMO.
 

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ChokolAwt said:
how exactly did you "whip up" a basemap in neptune? did you download the stock map and edit it from there? or is there a way to start from scratch and set a max manifold pressure on the map and max rev?
NepTune has a great basemap system (this car is on RTP) that makes it cake compared to the freeware solutions.

87TransAmGTA said:
i liked his welding mask lol
Heh... not to done at home ;)

imgoingforit said:
Aww, bummer. I thought there were updates.
There may be some updates soon. Jay had some issues with the engine itself, I'll probably be taking the civic in at WI and working some magic on it.
 

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downest said:
ChokolAwt said:
how exactly did you "whip up" a basemap in neptune? did you download the stock map and edit it from there? or is there a way to start from scratch and set a max manifold pressure on the map and max rev?
NepTune has a great basemap system (this car is on RTP) that makes it cake compared to the freeware solutions.
umm, but how exactly? I mean... i remember talking with matt and you need to pull like .5 degrees of timing for every pound of boost (compounded) and i found turboedit has a function for that... and fuel needs to incrase by 10% compounded and i found a function for that... but what i cannot figure out for the life of me, is how to "create" a basemap... do you start out with a stock map and edit it from there?

or is there like a blank map that you create?

could you go through the steps in neptune and maybe i can correlate parts of it to turboedit?

thanks
~Tim
 
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