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Discussion Starter · #1 ·
Anyone know why the changes I make to the boost tables section do not save or at least not seem to? I select "retard ignition by .75 degrees/lb boost" and "adjust for turbocharger eficiency 120%" ......press ok, and save the changes only to return and the option "Do not make changes" is selected for both the ignition and fuel.
What the hell is going on?
Also, under the fuel modifier calculator under both the "injector" and "engine capacity" sections any changes I make are either altered or returned to original settings.
I put in a new value of 450 for injector size, old engine capacity of 1834 (ls map, p30 base) and new engine capacity of 1972, click ok, and save changes
I open the fuel modifier calculator agian and the new injector size has changed from 450 to 418 and the engine capacities are both at the original 1595 setting.
 

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Discussion Starter · #3 ·
Thanks, but I'm actually looking for a more in-depth and well thought out response that originates from someone with a bit more sense.
May want to route your charge pipes through your foramen magnum and add a little pressure to your deflated head...
 

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OR ... you might want to route chrome to ebay :D

It is defaulting because Chrome operates using basic input calculations for a predetermined flow rate. This makes it much more difficult to mistune by restricting aspects of input the user can define.
Its going back to 418 because ... 450X1834/1972=418
Lets reverse that ... 1595X450/1972=364
Were you using 370cc injectors prior?

As for the turbocharger efficiency adjustment ... I have never even seen that in the unit. Where is that.

There should be an "adjust definable inputs" or "adjust for user definable input" box that is in operation which is making the unit calculate when you dont want it to. It is expecting a higher sized injector for your flow rate. This is my best guess with my whole hour of time logged on the system.
 

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Discussion Starter · #5 ·
Thank you for the legitimate response. The only injectors I have used with the chrome program are 450's. I assumed the 240's were default for the ls map? Am I to use 450 for both the old and new injector values?
I'll search through the options and see if I can find out what the hell is up.
Anyone else care to assist?
 

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Then that doesnt make sense to me because the way your old programming was set up, if what i said was actually what was going on, then the Chrome would have set the value as 364 AKA 370cc.
As for the boost compensation 120% ... I have never heard of this function and it isnt on my AEM so i have nothing to compare it to. I dont know what a "boost compensation" would be. Compensate for what? fuel, ignition, timing, boost, A/F, RPM v. boost? dunno.
 

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go to the faq and read about uberdata heath it will explain everything...i dont know any of the answer off the top of my head but i remeber reading quiet a bit about stuff along these lines... maybe email crome or go to their forum also? i dont see many people on here using it


average boost efficiency is refering to the heat created from the turbo/sc that makes are expand which it most turbos are around 75% BUT NEVER START WITH THAT.... they give you the value 120% to start with and you work your way down little by little to be safe
 

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Discussion Starter · #8 ·
ludeamister, I have read faq after faq, then posts and more posts. There is no clear explanation that I have located as of yet. Not saying it isn't out there but if it is I haven't found it. I've been on Crome's site as well as pgmfi.org and homemadeturbo.com searching for answers.The turbocharger efficiency is a percentage value that adjusts the fuel for the boost portion of the map from what I understand....but hell I could have that wrong also.The ignition can also be retarded an assigned value in degrees per lb/boost
 

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Your thread title translates as "Those afraid of chrome unite!", chromophiles is what you were after i think :p


Rather then retard based on boost, i'd think you ought to have a full ignition map, based on MAP and RPM, and a knock sensor to tune it with.
 

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i remeber reading something about if you have something turned on it wont save but i cant remeber what thats why i said its somwhere out there lol...im being vague but giving you hope lol
 

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ludeamister said:
average boost efficiency is refering to the heat created from the turbo/sc that makes are expand which it most turbos are around 75% BUT NEVER START WITH THAT.... they give you the value 120% to start with and you work your way down little by little to be safe
... That still makes absolutely no sense to me.

Heath said:
The turbocharger efficiency is a percentage value that adjusts the fuel for the boost portion of the map from what I understand....but hell I could have that wrong also.
I would be REALLY weary of a single % value altering your entire fuel map just for the simple fact that it would have to change the ignition/timing and fuel to correctly compensate.
My other thought is that a %, by definition, would remain a constant throughout the entire RPM range. However, it cant be a constant because fuel needs change along the RPM/fuel/timing axis.
Because of this, I think it is some thing different.
 

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Discussion Starter · #12 ·
Nope, I'm actually hoping there are other clueless and timid patrons like myself willing to unite and work through this madness. I'm aware ;)
I can't be the only one.....?
 

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Bobnova said:
Your thread title translates as "Those afraid of chrome unite!", chromophiles is what you were after i think :p


Rather then retard based on boost, i'd think you ought to have a full ignition map, based on MAP and RPM, and a knock sensor to tune it with.
they do give you the full table based on RPM and manifold pressure. that little box that you can enter the ignition retard per psi is only there to save the person the time of having to type in each cell of the spreadsheet one by one. as soon as you click to make those changes and view the ignition tables, you can see that they are all changed.

on the other problem, heath, i will open crome right now and see what i get. like i said before i have yet to run crome on my car, but i have had uberdata running though.

okay, i opened crome and did what you did.

file -> new -> P72 rom.
plugins ->advanced boost tools+, i chose stock honda map sensor and 8 boost columns. okay.

now if you look at your fuel and ignition tables you will see that all the boost columns have the same value in there across the board. you will need to run the tools->boost tables adjustments to recalculate the values. do this that choose 0.75 degrees/psi and 120% efficeiency. now if you go and look at all the value in the tables, the have changed accordingly. perfect. good.

if you run the boost tables adjust again, the "do not make changes" has been checked, but this doesnt matter since the tables have already been adjusted. don't worry about it. i agree that it kinda seems like nothing has changed, but it has.

with your other problem of injector scaling and engine size scaling. what you need to know is that the values as seen in the tables are not like uberdata. in uberdata the scaling multipliers actually change the values in the tables for you to see. in crome, however, the original values remain the tables for you to see, and the fuel multiplier is applied later. okay, now that we have this understood, you want to set the fuel multiplier.

by scaling to 450cc from 240cc, this gives a mulitplier 240/450=0.533 okay. if you click okay, you will notice that the colour of the cells change to a lighter colour. this lets you know that the multiplier has been applied, even though the values inthe cells don't change. if you then scale the engine size up to 1972cc from 1595cc this adds a multiplier of 1.236 for an overall multiplier of 0.659. this makes sense. when you click okay, the colours in the cells get darker, to let you know that the fuel multiplier increased.

when you open the fuel multiplier menu again, you will see that the multiplier of 0.659 is still there. what crome does is only store this multiplier. and then when you open the fuel multiplier menu it then fills in the value of ONLY the "new" injector size accordingly, based on 240cc and 1595 engine size. this is how you get 364cc injectors because 240/364 = 0.659. since the overall multiplier is still 0.659, then things are good. it would be better if crome saved the value of the injector size and the engine size, but it doesn't so as long as you know whats going on, it doesn't really matter. as long as your overall multiplier always stays at 0.659, then you are okay.

hope this helps
Russ
 

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are=air i dont know how i mispelled it wow... ok chemistry 101 when air gets hot it expands when it is cool it contracts... now a FI makes air HOT so air expands this average efficiency accounts for the air expanding... if air expands then less air actually gets into the engine...the point on an intercooler is to cool air so air is denser now an average turbo effiency is somewhere around 75% this is opposed to 100% (a 100% would mean the air does not change at all so the temp. doesnt change) you are told to start at 120% and wrok down so that way you dont screw up because you will be putting to much fuel and to much is better then not enough... with an intercooler your effiency is somewhere around 90% plus but if you guess you can screw yourself with giving the engine not enough fuel... however if you say that the effiency is 120% your really saying that the air is cooler then it started so its more dense....

Keahistight said:
... That still makes absolutely no sense to me.



I would be REALLY weary of a single % value altering your entire fuel map just for the simple fact that it would have to change the ignition/timing and fuel to correctly compensate.
My other thought is that a %, by definition, would remain a constant throughout the entire RPM range. However, it cant be a constant because fuel needs change along the RPM/fuel/timing axis.
Because of this, I think it is some thing different.
 

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It's a workaround to make sure you tune things too rich to start with basicly.

Most standalones use the air intake temp sensor to adjust that automaticly.
 

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^^ CROME has that too. fuel delivery adjustments as a function of air temperature, and coolant temperature. as well as cold start compensation and idle speed vs coolant temp. you can also change your closed loop disable points, based on throttle % and i think manifold pressure too.
 

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lmao 2.2L i knew someone was going to say it... aem isnt perfect nothing is...crome isnt either... they both have flaws and they both have strengths...crome is going to have stuff aem doesnt while aem is going to have things crome doesnt...no way to have everything
 
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