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Yup, every manufacturer is different, oem or aftermarket.......you’d be best to post a detailed question.
 

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Discussion Starter #4
Depends on what you want to know...........
What would you change on a stock tune, if you installed just a cam. 2007 6.0L LS2 .613/.576 lift 227/234 @ .050. Stock injectors, stock Throttle body. I'm basically wanting to know the reasoning behind the change.. the "why", if you will.
Thanks for any help....
 

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EFI/N2O JUNKIE
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What would you change on a stock tune, if you installed just a cam. 2007 6.0L LS2 .613/.576 lift 227/234 @ .050. Stock injectors, stock Throttle body. I'm basically wanting to know the reasoning behind the change.. the "why", if you will.
Thanks for any help....
I am assuming a stock ECM and going from a stock cam to your new cam. GM kills a lot of timing at the shift points and typically runs the engine pretty damn fat WOT. Even a stock engine can make more power with a "tune". As far as I am concerned though, if the stock ECM can run the engine at the correct AFR then it doesn't necessarily need a new tune. But you will need someone with a scanner or an aftermarket wideband and a sensor fitting in your exhaust to see what it is doing. If it is setting a check engine light then it is outside it's "expected" parameters and will need a new tune to keep it happy. Stock MAF sensors have a limit, which you won't need to worry about, but add a blower or a turbo and you will. It isn't the actual sensor, it is the stock ECM thinking something is really wrong with the MAF once you start pushing that much air past it and it goes into a limp mode...........
I only tune aftermarket ECM's, Holley, FAST, etc..... I have not bothered with EFI Live or similar setups to tune relatively stock combos. Not knowing where you are, Google East Coast Supercharging and send them an email, one of the owners is a member here, Doug is his name but I don't remember his screen name. They tune everything and also do a lot of tuning with the stock ECM's.
 

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Discussion Starter #7
I am assuming a stock ECM and going from a stock cam to your new cam. GM kills a lot of timing at the shift points and typically runs the engine pretty damn fat WOT. Even a stock engine can make more power with a "tune". As far as I am concerned though, if the stock ECM can run the engine at the correct AFR then it doesn't necessarily need a new tune. But you will need someone with a scanner or an aftermarket wideband and a sensor fitting in your exhaust to see what it is doing. If it is setting a check engine light then it is outside it's "expected" parameters and will need a new tune to keep it happy. Stock MAF sensors have a limit, which you won't need to worry about, but add a blower or a turbo and you will. It isn't the actual sensor, it is the stock ECM thinking something is really wrong with the MAF once you start pushing that much air past it and it goes into a limp mode...........
I only tune aftermarket ECM's, Holley, FAST, etc..... I have not bothered with EFI Live or similar setups to tune relatively stock combos. Not knowing where you are, Google East Coast Supercharging and send them an email, one of the owners is a member here, Doug is his name but I don't remember his screen name. They tune everything and also do a lot of tuning with the stock ECM's.
Thanks Mike. This LS stuff of my son's is a lot more complicated than my old 95 LT1 and Tunercat software. For instance, the way they set up adjusting injector flow is crazy. They adjust the pulse width by adjusting the End Of Injector Timing... Then, there's the "TQ Management" section....lol all of which is overwhelming to this old 67 year old brain of mine... But thanks for the help.. Gives me something to think about.
 

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Thanks Mike. This LS stuff of my son's is a lot more complicated than my old 95 LT1 and Tunercat software. For instance, the way they set up adjusting injector flow is crazy. They adjust the pulse width by adjusting the End Of Injector Timing... Then, there's the "TQ Management" section....lol all of which is overwhelming to this old 67 year old brain of mine... But thanks for the help.. Gives me something to think about.
I honestly don't know why they would adjust pulse width with the End Of Injector Timing, that sounds very strange. If you want the injector to be on longer for more fuel flow, I would just make the on time longer. If that time becomes too great for the EOIT then the injector has to be opened sooner in the cycle.

Basically, you have X amount of time to open and close the injector. If you can time it to start to flow at the "right" time with the intake valve opening, you decrease emissions and can still keep the A/F ratio where you want it. If you can't get enough fuel in there quick enough, you either need more volume with an increase in base pressure or a larger injector, or disregard the timing events of the injector opening/closing.

I have purposely ran injectors about twice as large as needed so we had PLENTY of room to move injector opening/closing around and not have an issue with delivering the proper amount of fuel. NHRA Stock Eliminator combos try everything and anything possible for more power!

Anyway, call/email/PM Doug from Easy Coast Supercharging and see if he can help you out. He does a lot fo ECM tuning via UPS, as in you send in your ECM, they will put a known pre-canned tune it your ECM and return it. This works for a lot of mildly modified combos.
 

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What would you change on a stock tune, if you installed just a cam. 2007 6.0L LS2 .613/.576 lift 227/234 @ .050. Stock injectors, stock Throttle body. I'm basically wanting to know the reasoning behind the change.. the "why", if you will.
Thanks for any help....
Need the entire combo.
 

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If the tune is stock then its going to be fat (rich) at wide open throttle for one thing. I guess most of us mod our cars for WOT gain so heres how to do that...

Adjusting this is under Engine > Fuel > Power Enrich > Power enrichment.

I've cut and paste this straight out of HP tuners for Power enrichment...

"[ECM] 12400 - Power Enrich EQ Ratio: This is the main table that is used to tune WOT fuel. The values in this table are Fuel/Air multipliers (or Equivalence Ratio) ie. values greater than 1 are richer, values less than one are leaner. The values relate directly to the Stoich AFR and the resulting commanded AFR is Stoich divided by this PE multiplier. Eg. if the multiplier is 1.1 then the commanded AFR will be 14.7/1.1 or 13.36."

You can lower those numbers in that table... it might be 1.2 or something stock, drop that number a little, and check with the wideband at wot, repeat till you get to where you want to be.

And you should have a wideband hooked up if youre going to mess with this table, but without one you could lean it out a little I guess.

What car is it btw, is it a swap or a standard LS vehicle. Transmission?

There will be plenty of torque managment also, cat overtemp, knock sensors... how much you might want to turn that stuff down (or off) can depend on how fragile the driveline is, if you are running cats, etc etc.

The timing wont be optimum either if its a dead stock tune, especially if you plan to run premium unleaded.

You shouldnt have to mess with the injector flow rates for now.

I could type all day about how to tune it 'properly' , but i'll just leave this guys vid instead...



He has quite a few on gen 3 and gen 4.
 

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Stock MAF sensors have a limit, which you won't need to worry about, but add a blower or a turbo and you will. It isn't the actual sensor, it is the stock ECM thinking something is really wrong with the MAF once you start pushing that much air past it and it goes into a limp mode...........
I only tune aftermarket ECM's, Holley, FAST, etc..... I have not bothered with EFI Live or similar setups to tune relatively stock combos. Not knowing where you are, Google East Coast Supercharging and send them an email, one of the owners is a member here, Doug is his name but I don't remember his screen name. They tune everything and also do a lot of tuning with the stock ECM's.
If you had messed with stock stuff, you'd find that Gen 3's with the 0411 PCM can actually max the MAF out NA, heads and cam, or even cam only with a really good intake tract and other things optimized.

Later stock ECUs added more range to the MAF table for more airflow.

But we like to remove them down under LOL, most do and run it speed density.
 

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EFI/N2O JUNKIE
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If you had messed with stock stuff, you'd find that Gen 3's with the 0411 PCM can actually max the MAF out NA, heads and cam, or even cam only with a really good intake tract and other things optimized.

Later stock ECUs added more range to the MAF table for more airflow.

But we like to remove them down under LOL, most do and run it speed density.
Let me ask you this: Do any of these cars/trucks come with a wideband sensor or are they all narrow band?
I know with a MAF, Air Temp and Water Temp you can get a decent tune in a combo without using a wideband.
But once someone tries a good system like a Holley, FAST, or Big Stuff (and Haltech) with a real wideband, now they see how easy this stuff can truly be and forget about those stock ECM's.
 

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Well the LS stuff is narrowband, some cars are moving to wideband, ive never dealt with a vehicle that has factory widebands though.

And sure you can bring up the narrowband o2 numbers with Hp tuners. You can even just tweak the one power enrichment table I mentioned earlier for WOT mixture and run some very quick numbers without having used a wideband, by leaning it out (reducing the multiplier number) until the car goes the quickest.

But you can also tie in a real wideband to the stock ECU using an unused 0-5v input (like the EGR or air conditioning pressure switch), log your MAP vs RPM error percentage (commanded vs actual) and tweak the MAP v RPM table so it runs right where you want it to everywhere.

 

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Well the LS stuff is narrowband, some cars are moving to wideband, ive never dealt with a vehicle that has factory widebands though.

And sure you can bring up the narrowband o2 numbers with Hp tuners. You can even just tweak the one power enrichment table I mentioned earlier for WOT mixture and run some very quick numbers without having used a wideband, by leaning it out (reducing the multiplier number) until the car goes the quickest.

But you can also tie in a real wideband to the stock ECU using an unused 0-5v input (like the EGR or air conditioning pressure switch), log your MAP vs RPM error percentage (commanded vs actual) and tweak the MAP v RPM table so it runs right where you want it to everywhere.

Thanks for sharing your information.
 

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Well the LS stuff is narrowband, some cars are moving to wideband, ive never dealt with a vehicle that has factory widebands though.

And sure you can bring up the narrowband o2 numbers with Hp tuners. You can even just tweak the one power enrichment table I mentioned earlier for WOT mixture and run some very quick numbers without having used a wideband, by leaning it out (reducing the multiplier number) until the car goes the quickest.

But you can also tie in a real wideband to the stock ECU using an unused 0-5v input (like the EGR or air conditioning pressure switch), log your MAP vs RPM error percentage (commanded vs actual) and tweak the MAP v RPM table so it runs right where you want it to everywhere.

My buddy has been doing this. He started on his project a few years ago. He would like to buy the new Holley stuff, he has more into his stock ECM/harness/HP Tuners than Holley is selling their new LS kits for...............
 

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My buddy has been doing this. He started on his project a few years ago. He would like to buy the new Holley stuff, he has more into his stock ECM/harness/HP Tuners than Holley is selling their new LS kits for...............
Sure, I understand. Our LS cars here were holden sedans that were mass produced here, so the PCMs and looms were everywhere and quite inexpensive for people who are able to trim the looms down and do things themselves...though they are becoming less common now, there are less for sale as the cars age.

For those who cant get or modify a cheap loom.... if you start buying ready made LS looms for stock PCMs then HP tuners etc etc you start heading towards aftermarket $ territory. Though here stuff costs more, a terminator x is 2k here.

Of course many people mod vehicles that are already LS, so they dont want to wire in an aftermarket ECU to a late model vehicle, which would affect all the other systems because the BCM and other modules wont work with it in the GM cars. Id say down here the majority of lightly modded LS engines are in their native late model holdens so its just not worth messing with those... but if someone is doing a swap, or want to go really quick, different story.

People have gone 8s here in the 1/4 with stock PCMs on both the LS holdens and the ford barras.

Depends on the application I guess, I would avoid removing a factory PCM on a factory late model LS holden for example for as long as i could, so that other things on the vehicle work as they should.
 
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