What timing MAP to pull timing from for nitrous?

s8v4o

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I'm still familiarizing myself with the PRP. I want to pull 3 degrees of timing with anything over 3000 RPM and a load greater than 0.3.

I know the ECU takes all the information from all the tables and uses the least amount that's calculated.

BORDERLINE_KNOCK_TABLE + SPARK_ADDER_TO_BORDERLINE_FOR_IMRCs + SPARK_ADDER_FOR_A/F_WHEN_OPEN_LOOP + (SPARK_RETARD_ECT_MULTIPLIER times SPARK_RETARD_FOR_ECT) + (SPARK_RETARD_ACT_MULTIPLIER times SPARK_RETARD_FOR_ECT) + (some VCT stuff) + OCTANE_PLUG_SPARK_MODIFIER.


So which table should I take the timing out for nitrous? Thanks.
 

s8v4o

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Are you referring to "Borderline Knock table"?
 
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s8v4o

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Yeah. Some people copy and paste that table from 30% load and up to the MBT table but I don't. Up to u.

I thought about using that table but the description says

"This is the spark to prevent engine from knocking when running 14.64 AFR"

So it's kind of confusing because when running WOT it should be in open loop and not running a 14.64 AFR.

The "Spark adder for AF when in open loop" seemed promising but RPM is on the X axis and Lambda is on the Y axis (not load).

Have you used the SCT software, Advantage III or the PRP?
 

05mustang_TT_charged

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If you use the Border Line Spark table go to the MBT table and add 4 degrees to it and it should just operate on Border Line Spark table.

Since it will be using the tables with the least timing in it. This is what I have been reading up on and that is the way they said it for when I want to pull timing when on a 2 step. I'll check again when I get home to be sure. Are you a member of the SCT Forums? If so in the PRP section they explained it.
 

Alfiedagr8

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Base borderline is the base timing it uses. Then it takes in account all multipliers and adders. What I like to do is add one in global to make the car feel "lighter" in city driving and note that u added one deg in wot aswell so remove that deg from the base borderline table at the wot levels . I haven't used that software I use hptuners and DF.. Also u may have have to turn off IPC u may get a wrench light if u don't.
 

s8v4o

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If you use the Border Line Spark table go to the MBT table and add 4 degrees to it and it should just operate on Border Line Spark table.

Since it will be using the tables with the least timing in it. This is what I have been reading up on and that is the way they said it for when I want to pull timing when on a 2 step. I'll check again when I get home to be sure. Are you a member of the SCT Forums? If so in the PRP section they explained it.

I see you're in LSU country. I'm in BR and graduated from LSU. :thumb: Should I be adding or subtracting the 3 degrees in the MBT table? Am I making changes to the Borderline Knock Table and the MBT SPark Table. I read the description on the MBT Spark Table and it mentioned that changing this would not affect the engine timing so I wasn't sure.

No I'm not a member yet of the SCT forum. Guess that should be next on my list of things to do.
 

s8v4o

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Base borderline is the base timing it uses. Then it takes in account all multipliers and adders. What I like to do is add one in global to make the car feel "lighter" in city driving and note that u added one deg in wot aswell so remove that deg from the base borderline table at the wot levels . I haven't used that software I use hptuners and DF.. Also u may have have to turn off IPC u may get a wrench light if u don't.

Thanks, is that what you do for your nitrous tune?
 

lito

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I thought about using that table but the description says

"This is the spark to prevent engine from knocking when running 14.64 AFR"

So it's kind of confusing because when running WOT it should be in open loop and not running a 14.64 AFR.

The "Spark adder for AF when in open loop" seemed promising but RPM is on the X axis and Lambda is on the Y axis (not load).

Have you used the SCT software, Advantage III or the PRP?

You were close to answer your own question right there.

The description is correct except maybe the 14.64 mention, lambda 1 would be more accurate now, but the description I understand has been there before the ethanol days. There are many things like this around the tuning softwares because what people was used to around those days, I hope to see that corrected some day, specially Diablosport's way of representing base fuel table in AFR instead of lambda.

The calibrator that designed the model has to set some bases, this is one of them, this table determines the spark that borderlines knocking on certain standard conditions (lambda 1, 100 ACT, 200 ECT, ect) where all the adders apply, including the lambda referenced, that is why you see that this table adds 0 at lambda 1, adds on richen and retards on leaner conditions.

MBT, works as a clip because of what its name specifies, more spark than that will not render more torque.

Some people just zero the lambda adder and works out only of BKT, choose the way that works for you. It all depends on what you've done on your BFT.
 

lito

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Also u may have have to turn off IPC u may get a wrench light if u don't.

facepalm.gif
 

Alfiedagr8

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What I do is just subtract from base borderline your 3 deg. From 70load and up and thru all rpm range. MBT is reserved torque and it refers to that table when it needs more torque example. When ac is on. It uses for smith idle and cruise. And yeah it does use the smaller of the two tables. People like to copy and paste these table over 30 load cause they know exactly what the car is Gonna do. In this case I leave it alone. But the choice is always yours. And I didn't pick the location were I'm from. Guess I skipped it. I'm from Bakersfield CA. And u? Hope this made sense to u. And if u happen to get a wrench lamp after A few pulls just fix IPC.
 

s8v4o

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You were close to answer your own question right there.

The description is correct except maybe the 14.64 mention, lambda 1 would be more accurate now, but the description I understand has been there before the ethanol days. There are many things like this around the tuning softwares because what people was used to around those days, I hope to see that corrected some day, specially Diablosport's way of representing base fuel table in AFR instead of lambda.

The calibrator that designed the model has to set some bases, this is one of them, this table determines the spark that borderlines knocking on certain standard conditions (lambda 1, 100 ACT, 200 ECT, ect) where all the adders apply, including the lambda referenced, that is why you see that this table adds 0 at lambda 1, adds on richen and retards on leaner conditions.

MBT, works as a clip because of what its name specifies, more spark than that will not render more torque.

Some people just zero the lambda adder and works out only of BKT, choose the way that works for you. It all depends on what you've done on your BFT.

Thanks Lito. Some tuners are reluctant to post information as they think it will take away from their business. So on that note I thank you! By BFT do you mean Base Fuel Table? So far it seems that I might be best off subtracting 3 degrees of timing from the BKT from 3000RPM and a load greater than 0.299 to compensate for a 75 shot off my current tune?? I have a MTF file if you would like to take a look.



?

What I do is just subtract from base borderline your 3 deg. From 70load and up and thru all rpm range. MBT is reserved torque and it refers to that table when it needs more torque example. When ac is on. It uses for smith idle and cruise. And yeah it does use the smaller of the two tables. People like to copy and paste these table over 30 load cause they know exactly what the car is Gonna do. In this case I leave it alone. But the choice is always yours. And I didn't pick the location were I'm from. Guess I skipped it. I'm from Bakersfield CA. And u? Hope this made sense to u. And if u happen to get a wrench lamp after A few pulls just fix IPC.

How much nitrous u running and octane u using?

I'm from Baton Rouge Louisiana. I'm going to be running a 75HP shot on 93 octane. Seems modifying the BKT is the way to go for me?
 

elky406

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Borderline but watch your source file logging to.make sure its not in mbt if its in mbt just copy your borderlineand paste it to mbt.
 

s8v4o

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Borderline but watch your source file logging to.make sure its not in mbt if its in mbt just copy your borderlineand paste it to mbt.

My BKT and MBT tables are very similar. My two tables at and below a load or .499 and above 2250 RPM are exactly the same. At and above a load of .599 vary very little. Variance is only between 0 and 3 degrees for the upper right part of the tables. Should I make these two tables identical above 3000RPM and above .599 load?

Subtract from load greater than .7 and up. Don't go as low as .3 it's point less at that point.

Why 0.7? I was saying above 0.3 to be safe. After datalogging it appears that the load quickly changes from .2 to .8+ almost instantly. So on that note 0.7 seems okay I just want to be sure
 

05mustang_TT_charged

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I am under the impression that if you subract the 3 degrees from the BKT and add 4 degrees to MBT. This will only allow the car to run off the BKT as it is the lower of the 2 tables. I went and added 4 degrees to the whole MBT to make the car use the BKT.

I am not 100% sure if this is the correct/best way to do it but that is what I was advised to do. I only wanted to deal with one table (BKT) and not have to worry about tuning 2 tables (BKT & MBT).
 

lito

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Thanks Lito. Some tuners are reluctant to post information as they think it will take away from their business. So on that note I thank you! By BFT do you mean Base Fuel Table? So far it seems that I might be best off subtracting 3 degrees of timing from the BKT from 3000RPM and a load greater than 0.299 to compensate for a 75 shot off my current tune?? I have a MTF file if you would like to take a look.

There is no complete manual in this stuff, obviously we all got help from others, some a little, some more at the beginning. Many of the stuff you have to deduct and test for yourself and that requires time and work so is normal that tuners that are in the know are not willing to share some of that stuff, I share that point of view.

BFT is base fuel table, two top rows of BKT usually is enough, considering your location you will be working on the top row most of the WOT time.

Get into the PRP forums, there is a lot of info there, not all is correct but many dealers go there to help PRP owners.


No one that knows what the IPC does would ever tell anyone to disable it.
 
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