You have to look at the entire Calibration as a whole entity. There is no magic table. They will all need the associated tweaks etc to get working correctly.

The whole issue you were having was that you were going after the MAF table. You should have gone after the OLFA and the VE table. As I have said before the VE table is used just not the way you think its being used. Treat like Acceleration Enrichment. It is essentially being used as a large TPS Modifier table from the factory.


As for the air backing up. I would like to see some proof of this. I know of another person that has made those claims only to be disproven when actual testing was performed. Watch the pressures in the MAf ducting if you wish to test this hypothesis.

Considering I have worked with cars that have cams in the 250+ zone with the MAf and they run well I don't see where your argument really lays in the issue.

Again I didn't say SD couldn't work its just that it breaks the OS. It won't work as well as a properly calibrated MAF version will.

Also when you force the PCM to SD mode a whole host of nanny features turn off in the PCM Like idle adaptives which make the car run better.

 

ok, then what's your model? how do you tune? stop dodging the question and give me a derivation of a new way of doing things, or at least prove (rigorously) how old things are wrong.

 

There is enough info in this thread on how it works for you to figure that out. There is no way you are going to model dynamic airflow in a tunned runner system with any margin of sucess beyond rough calculations. To many dynamics. You just going to have to screw around with it.

I tune very differently from this whole group that much is fairly obvious. But giving away hard earned knowledge isn't something I am willing to do.

 

so you're gonna bitch us all out but not give us any solutions. great. very useful, thank you for playing.

 

In re-reading some of this thread, this topic struck me kind of funny. Am I correct in understanding your interpretation of our method of tuning is it's a problem or cause for oil consumption and piston ring deterioration, resulting in blowby? Considering a good guess is less than 5% of the tuned H/C cars are tuned 'our way' (since most pros don't have the time and most people don't want to learn to do it themselves), that would be a bit of a bold statement - don't you think?

My car, for example, has had oil consumption issues since the day I bought it (only 34K on the clock IIRC). The pro who installed the hardware and tuned the PCM at 24K miles used your method of tuning by altering the Open Loop/PE tables and leaving the MAF alone. Let's set aside the fact that he had my timing jacked way up in the lower RPMs (10~15* or more in some spots), which resulted in bucking/surging, KR nearly everytime I pulled away from a stop, and the occasional low-end miss. The overall driveability of the car when I got it was crap. It would surge at anything below 1700rpm, you couldn't go anywhere the first 30 seconds or so after you started it up or the idle would hang and fluctuate, the AFR was all over the place, idle would suck anytime you were stuck in traffic, it'd cruise control itself on the highway because the IAC was jacked up quite a bit (cracker and follower)......and this from a 'pro' who's actually a sponsor on THIS site! Now, I don't know how your cars specifically turn out. But, these types of results seem fairly consistent as a friend of mine had his 224 cam tuned the same way. His fueling was off as much as +/-10% at any given time....not to mention his 'professional' tuner told him the culprit of his surging was his new 3500 stall and that he should call them to complain. When I pile that experience in with the frequent complaints we see in this section from people who just took their car to a shop for a tune (and even the ones who don't complain right away because they're semi-blinded by the WOT dyno results), I'd say there's more evidence for our way of tuning then against.

Granted half of that last paragraph is me venting....I just don't see our tuning methods being any more or less of a cause for oil consumption (or any other mechanical failure) than your way. And on top of that, how are you even losing out on sharing what you know?

1) It seems it'd take a hell of a lot of convincing on your part to prove to us your right and we're wrong based on what we see day to day.
2) Tuning cars is a fairly localized type of business. People aren't going to drive 4+ hours to have you tune their car unless unless the sign out front says Lingenfelter. And if they are willing, they're not to type of people that would come to some do-it-yourselfer to have their car tuned.

One more thing I don't get....you say you have all of this insight to how the PCM works and the way it was meant to make certain calculations to achieve the desired pulse width or AFR. To me, someone with this knowledge shouldn't have a hard time deriving a scientific method that would allow you to change the appropriate tables the right way to get a desired result. Yet, you say, "You['re] just going to have to screw around with it"???
I'm getting tired of arguing this thread again because I'm starting to sound like a freakin' lawyer recalling prior testimony. So, I'll probably drop out for a while. But, I may be back...

 

Give away "Hard earned knowledge?" I thought that was what the entire purpose of this board was... a place to share knowledge.

No soup for you.

I suppose you lock customer's tunes as well. I equate that with someone inviting you over to dinner, excusing yourself to the restroom, locking the door, taking a stinky dump and crawling out the window.

 

Nope no PCM locking. Just asking me for the entire method is like asking for a freebie. Again I have put enough information in this thread for you guys to figure it out. Read what I am saying very carefully the answer is there.

As for mathmatical formulas I don't use any.Test and change and test and change. All tunning work is essentially iterative testing.

 

ok, let's summarize: your method is to do no changes to MAF ever, make and arbitrary (aka whatever works) changes to VE and OLFA table, is that your method?

 

Even the factory calibration is to rich for the ring design in the engine.

I am saying your focused effort to achieve 14.7:1 is the cuase of the blowby not the exact method.



I would agree that it sounds like the "Tuner" didn't do a very good job. the car should have been sent back with the expecatation that it actually be fixed.



Honestly.I lose out not becuase you the avg joe get the info but becuase the Pro Tunner Steals the info half *** applies it and still no fixs.


Hmmm Take it or leave it. This is a topic for discussion. You can choose to use any method you want.


Yeah essentially. Your going to have to screw around with it. If you put together all the info I have given you so far you could easily construct your method. I have given you more then enough info on the fueling algorythm.Even if you did have the factory algorythm in its entirety it still would most likely not deliver the results your after.Its essential aim is to keep fueling in a very specified band for cat efficiency. Not exactly the type of driveability your after.

Essentially a method like this would work.

Assume that with the OLFA set at 1.0 in the normal operating temp zone that whatever the AFR is that it is essentially correct. Regardless of what the wideband tells you. Set your PE enable to 100% and you PE values to 1.0 as well. Start working on the VE table from there to achieve the desired Tip in throttle response.

Now start working the PE table to bring the High load fueling in where you like it.

Scale the OLFA table for cold start performance and you 50% the way there.

Also don;t be affriad to workt he timming table. Alot ot time just working the timming table without working the VE table and the PE table will bring AFR closer to being in line.

then get back to working VE. Start with Steady state first then move to transients then to WOT fuel.

And no there is no Math for me to give you on this one.



don't think of it as an argument. challenging preconceptions about things is always an oppurtunity to learn. I know I have heavily considered the SD option for a few cars but overall Being diligent and working at it has always netted the desired result.

Also don't think that I don't like Sd. I do like it when the system is truly capable.

 

You could essentially use % devations to bring the fueling to where it works the best but there is no one optimal AFR. BSFC is going to do funny things with load demands and unless everyone starts running the same cam,head,compression there is nothing but rough geusstimation.

 

I keep hearing this and I keep getting confused. Are you saying that this table is not really EQ like the software says? If not and it really is EQ, then 1.0 in the cells equals stoich divided by 1.0, which is stoich (i.e. value of B3601). At idle with an OLFA value of 1.0, a stock VE table, and a stock MAF table, my WBO2 will read somewhere around the high 11's or low 12's (what I mean when I say pig rich), the car struggles to run on its own, and I'm now wearing a new scent (Gasolín de Mechaníc by Chevrolet).

>>common response to the new scent>>

I would think this is a common thing for any cam or head/cam car. Yet, you tell me it's the reverse. That, given that situation, the car should be lean down low (in the eyes of the WB) and richen up (or clean up to use your words) as RPMs increase.

That's why I'm confused...

 

I have never seen that behavior. Are you sure that your injector size is set correctly in the Calibration ?

Put the table values your using for your injectors up ?

 

I entered 4.55 grams per second for the 0kPa cell, 4.98 grams per second for the 80kPa cell and did a linear fill for all the cells in between.

They come out to:

4.55 - WOT
4.58
4.60
4.63
4.66
4.69
4.71
4.74
4.77
4.80
4.82
4.85
4.88
4.91
4.93
4.96
4.98 - full vacuum

That's using the spreadsheet with 30lbs/hr@40psi rated and 58psi actual. The original tune actually had numbers about 5% lower than that (or 5% richer - however you want to look at it).

I'm pretty sure those are right. The injectors are said to flow like 36lbers in our cars. I show a 25.6% increase in the table over the stock injectors. 1.256*28.8=36.2

 

Not just you dude, EVERY cam or H/C car I tune is that way and 95% of them have the factory injectors and tables in from the get-go, so you (ls1curious)can't blame that.

Ls1Curious, sorry, the idea of them being falsely lean is WRONG. Idle MAP of 55kpa says it all as well.

 

these are the FMS EV1 style injectors ? 30pph ?

 

SVO Red Tops rated at 30pph

 

rated flow pressure on those is 37.5psi @ 30pph. they are very non linear with pressure rates. Id advise figuring them at almost a 44pph injector @60 psi pressure. I don't have the flow data on those. I will ask around and see if anyone has it.

 

Very interesting you think I am bitching some one out.I am bitching at no one. I am making a statement about how the OS works and everybody gets alarmist. Maybe folks here are a bit to touchy.

I did catch your posts on the EFI Live forums however. the point of my post is to say that the original IAT ECT calculations stay intact if you don't run SD. Alot of the Calculations you are reffering to are humidity corrections which are rough to say the least. If you want the entire fueling algorythm in its entirety I will see If i can paste the whole thing together for you with the Math. warning even if you have it most likely it'll be fiarly confusing without all of the various adders and scalars.

How are you with C code ?

 

You have the source?

 

Yeah i said that like 50 posts back.