Simple MAF/DYNAIR pid question.

[acomp917]

This the whole post, I seem to be having a delivery problem. That along with the "personalized" thread jacking is causing me problems.

RHS posted:

Quote:
VE*MAP/charge temperature

273.15+IAT+((ECT-IAT)*factor) where factor is obtained from this calibration.

Its a myth..
of course it's not gonna agree, for multiple reasons:
1. you're using VE not GMVE, so you're missing VOL and R
2. if you were using GMVE and checking your units, you'd be forced to use Kelvin for temps everywhere, which btw is the proper thing to do.
3. this model does not work for all model/years. newer cars have the Lag filter involved. even newer stuff has the bias table is dependent on airflow and speed, instead of just airflow alone. so which model are you testing on what platform?
__________________

That is where things started DOWNHILL. Thanks, Marcin!

S, thread owner

[redhardsupra]

why would you name a car Probe? unless you're into dropping soap...

[acomp917]

Dam Marcin,

Have you run out of meds? Remember, before you were too smart to relate to others you spoke english(assumption). If you would remember where you have been...you will remember where you come from.

At my age I do not need another enemy, although I can live with that.


Now! have a beer.

S

About that soap: Since the military, I only shower with members of the opposite sex. and THAT is what makes me happy.

[joecar]

...

Why would anyone call a car "Maloo"?

This is not an acronym, ebonics, webonics, or any other Nonsensical Talk. Just trying to be funny.
...

It's the same marketing concept as "Camaro" and "Chevelle"... they are the proper names of mythical creatures yet to be discovered.

[redhardsupra]

why would you name a car Probe? unless you're into dropping soap...

that supposed to be a joke, since you wanted to lighten up the mood.

And no, I was too smart to relate to people long before I spoke English. That's actually only a half-joke

[acomp917]

joecar,

What are you, an alien? Those cars are AMERICAN heritage! What do they have to do with that car named "Maloo"? Oh, wait, this is the WWW. Am I being ignorant again?


S

If I ever market a car, I'm gonna call it the "PLATAPUSSY". (One too many beers for me)

[joecar]

See my inline comments in blue ink...

RHS,

After looking at that post, I cannot make anything from it. It seems to be incomplete. I'm still not sure what you call "charge" temp. Is this the IAT with another modifier or 2 included? ie. ECT blend, or MAT.

VE*MAP/charge temperature
What does this represent?
VE has units g*K/kPa, so VE*MAP/temp has units g (i.e. grams or grams/cylinder).

The ideal gas law is: PV = nRT = (m/M)RT
where:
P = pressure
V = volume
n = mole count
m = mass
M = molar mass (which is a constant for any particular gas)
R = gas constant
T = temperature (absolute temperature, degrees Kelvin)

If you rearrange the gas law you get: mT/P = V(M/R)
notice the left side has units g*K/kPa (and that (M/R) is constant)...
i.e. V(M/R) is our VE table value...
rearrange further: m = V(M/R)*P/T = VE*P/T = VE*MAP/temperature

i.e. the VE table contains the cylinder airmass scaled ("normalized") for pressure and temperature...

(when I say temperature, that is the blended charge temperature... see next point).

273.15+IAT+((ECT-IAT)*factor) where factor is obtained from this calibration.
What factor does this represent? What is "this calibration"?
This is the charge temperature which is a blend of IAT and ECT.
The 273.15 converts it to degrees Kelvin (absolute temperature).

...

S

[joecar]

joecar,

I think we argue over semantics. I learned this stuff without ever reading a book or taking a class(used internet). I started this in the days of the GM 7747 ECU(hated those). My verbiage is usually wrong and my thinking is sometimes wrong.

I am eager to get some basic tuning done in order to see if I have wrecked the VE MAF relationship. I have been rough on the tables. Got fairly good at bashing in tables from setting up aftermarket EFI on most any engine combo that people wanted to build. This MAF system is slightly different and considerably more balanced. It is good that I decided to learn this system on a stock engine(read: easy).

Questions:
1- What are you doing with all of the other(not main) 3d timing tables?
2- Is there a big problem when they are not close to the main table?
3- Do you think I should analyze them in relation to the stock main table and and apply those differences to them based on my final modified main table?
4- Should #3 be done before any serious tuning?
5- What is ICE textbook?

I'll leave you alone after this,
S

PS, Seems that edits are emailed to subscribed members. I been goofin with BB code. Must look like a GOOF.

It's not semantics...

delivered fuelmass and calculated fuelmass are different things... just like measured AFR and commanded AFR... the difference in what they are will drive your thoughts...

I learned this stuff by reading/asking/doing... I'm still scratching my head (I feel like a newb everyday)... ...you're in for a good learn, probably the best in your whole life ever...

1- the other timing tables (3D and otherwise) provide adjustments for temperature or for other engine modes... you make sure you run/log in the zero correction regions (or filter out anything outside of this) so you can ignore them;

2- maybe or maybe not... but, there has to be a reason why;

3- concentrate on the main table, but you will need dyno time or and/or dragstrip time;

4- I'm not sure... timing is difficult to set.

5- ICE = Internal Combustion Engine... I usually pick up a textbook or two every so often when Amazon has some kind of sale/deal... I'm slowly reading my way thru Heywood "Internal Combustion Engine Fundamentals"... long dry read with lots of engineering maths/charts (not for the non-engineer)... ...Heywood is the engineer's equivalent of a "hero"...

[acomp917]

RHS,
Call me radical, I never liked fords. Chevy's forever!.

joecar,
I'll be back in a year to discuss this information. I do remember some of this from chemistry. I think my notes have crumbled due to erosion.

S

[joecar]

joecar,

What are you, an alien? Those cars are AMERICAN heritage! What do they have to do with that car named "Maloo"? Oh, wait, this is the WWW. Am I being ignorant again?


S

If I ever market a car, I'm gonna call it the "PLATAPUSSY". (One too many beers for me)

Yes I am an alien... actually a resident-alien, I forget what my permit says...

American heritage, yes, I agree... but where did those names originate (nothing to do with www)...

(a Platypussy would [arguably] be named after a mammal... but a Camaro or a Chevelle is neither an animal nor a thing...).