tuning? good input wanted no bashing!!

[redws6rocket]

hey guys, i want some good tuning input from some of you guys that do alot of tuning! i have some questions that i have in my head with out any good answers. first of all i have seen several different tunes and logs that i have from many trucks, everybody does things different! for instance i have logged a truck puller buddy of mines that is done by tts, and he has injector pw in the 3000 range, while i have another tune from jpowell, who has been helping me and his tune is in the 2300 range? that part i don't understand, i also have some fleece stuff and it is around the 2600 range? these are all big injector, big charger, built motor tunes? any input from you guys!

another thing from my truck pulling buddy is max timing is at 24, it was recently bumped up to 29. we were also told that egt's would be much hotter, so is more timing more power? also shortly after this the truck cracked a piston too?

like i said i did not want to include names, we all know who tts is. this not the point, i want some input from you guys on the above. i would like to know if you really need to have an injector open that long to make power or not. i do not want this to be another bash on somebody thread please!

thanks guys!

 

[GeneralTJI]

I tune a lot more gas stuff than Diesel, so I don't claim to be an expert on these trucks... but yes more timing is more power up to a point. If you light it too soon, you actually lose power because the force of the burn hits the piston while it's still traveling up. Cylinder pressure is higher with higher timing (which means more push) But again, too early kills power and is hard on the motor when your shoving straight down before the piston goes past TDC. Low timing generally will increase egts and power will be down due to inefficiency (piston is running away from the burn). There is a happy medium like with most things. I used the timing calculator to get me in the ballpark, then tweak from there. Timing is related to pulsewidth (how long the injector is spraying)... so bigger injectors require shorter pulsewidth to do the same thing which means less timing is needed.

 

[DAVe3283]

I run a 2300 us pulse, and honestly, I don't think that is all that much power (well, compared to stock it is!). 3000 is toward the max I've heard of people running on a stock engine. The pulsewidth relates to power much more closely than the timing, assuming the timing is set appropriately.

Why did your buddy bump the timing from 24 to 29 degrees? Honestly, I'd expect EGTs do go *down* slightly after that change, unless more fuel was added as well. This could have cracked a piston, 29 degrees is up there a ways, but I wouldn't have expected it.

It is hard to tell what a tune is built for by looking at the WOT pulsewidth. And timing is meaningless unless their is a pulsewidth associated with it. For example, there is nothing wrong with 24 degrees timing, but if your pulsewidth is only 1200 us, then you might not like the result. But if it was 2500, it would work OK. Also, what RPM were those at? Because, 2500 uS and 24 degrees works fine at 3200 RPM, but not so well at 2000 RPM.

 

[CamaroZ]

Off topic but it's good to see a familiar name from LS1Tech! wish I could help you more but I've only had my truck for 5 months and still playing with EFI..

 

[Rhall]

hey guys, i want some good tuning input from some of you guys that do alot of tuning! i have some questions that i have in my head with out any good answers. first of all i have seen several different tunes and logs that i have from many trucks, everybody does things different! for instance i have logged a truck puller buddy of mines that is done by tts, and he has injector pw in the 3000 range, while i have another tune from jpowell, who has been helping me and his tune is in the 2300 range? that part i don't understand, i also have some fleece stuff and it is around the 2600 range? these are all big injector, big charger, built motor tunes? any input from you guys!

another thing from my truck pulling buddy is max timing is at 24, it was recently bumped up to 29. we were also told that egt's would be much hotter, so is more timing more power? also shortly after this the truck cracked a piston too?

like i said i did not want to include names, we all know who tts is. this not the point, i want some input from you guys on the above. i would like to know if you really need to have an injector open that long to make power or not. i do not want this to be another bash on somebody thread please!

thanks guys!

I would think a lot of the pw has to do with injector size, and how much fuel the turbo cleans up. Theres a calculator for timing and how it relates to pulse width. We had a lot of help tuning my truck, Rob Coddens, and Johnboy, and we kinda did it by smoke. When we were running our first charger this year with my big injectors we were running a really low pulse width, and couldnt clear anything up, just wasnt getting the air it needed. After changing to two different garrett chargers we have came up around 700us on pulse from where we started, and it still clears up more smoke, with the raised pulse we also raised timing. I know timing and a lot of pulse can also crack pistons as you start spraying outside of the bowl when you raise pulse. Thats why its better to stick with huge injectors and a lower pulse to keep the spray pattern tight. If its whos truck im thinking of, i dont think 29 degrees on timing is way out of line, depending on when it hits it. Id say that the 3000pw might be spraying outside of the bowl a bit. With my 60% overs last year, Rob and I decided not to take it over 2900 us in fear of spraying outside of the bowl. We are lower than that now, but i have much bigger injectors, we hit over 29 degrees of timing also. Im by all means no expert to tuning, i just listen and try, and Tim and I kinda decide what we do week after week depending on how everything looked the week before. So if i said anything way out of line, i wouldnt be suprised.

 

[IOWA LLY]

I wouldn't believe anything you see in a log from a locked ECM........

 

[Josh2002cc]

I wouldn't believe anything you see in a log from a locked ECM........

Really, well return my text you moron. :baby:

 

[duratothemax]

I wouldn't believe anything you see in a log from a locked ECM........

I would....

The ECM reports exactly what it is doing at any given point. You cant prevent the ECM from transmitting live data over the bus. Otherwise the cluster, TCM, TCSM and all other stuff in the truck that depends on engine operation parameters wouldnt work.

Now, im sure there are people out there who will BS and tell you "oh but you can make the ECM lie and make it tell the Tech 2 that its running 27* of timing when in reality its running 30*!!!" but im sorry, they are full of crap. If the tech 2 is giving you any data at all, its the right data.

Ben

 

[redws6rocket]

I wouldn't believe anything you see in a log from a locked ECM........

with my tech 2 i can see exactly what happens, i have taken many shapshots and emailed them. i don't see how the tech 2 info would not be exact? not to argue i just don't see my gm tool not reading the correct info?

 

[redws6rocket]

thanks for the input guys, i hope to get some more guys to chime in and help!

 

[duratothemax]

with my tech 2 i can see exactly what happens, i have taken many shapshots and emailed them. i don't see how the tech 2 info would not be exact? not to argue i just don't see my gm tool not reading the correct info?

People who make locked/secret tunes would like you to think that they can fool the ECM somehow into giving you incorrect data readouts, to discourage you from "copying" the [locked] tune.

 

[IOWA LLY]

Believe what you will. I never said everything the ecm is reporting out is skewed, but the TCM or TCSM doesn't care what the pulsewidth or timing is.......

I have seen proof of such things but I myself have no idea how it is accomplished or how to do it myself. All I am trying to do is help, but go ahead and copy what you see in the log and see how well it works for you.

 

[duratothemax]

Believe what you will. I never said everything the ecm is reporting out is skewed, but the TCM or TCSM doesn't care what the pulsewidth or timing is.......

I have seen proof of such things but I myself have no idea how it is accomplished or how to do it myself. All I am trying to do is help, but go ahead and copy what you see in the log and see how well it works for you.

Really? How do you know? If you have a magic ECM that can "fool" the data stream that feeds the tech 2 pulsewidth and timing, then how do you know what the timing "actually" is and if its different from what the tech 2 is reading?

See what I mean?

thats like saying "well I have a thermometer that has been setup to lie about the actual temperature" and then in the same sentence saying "I know the actual temperature"

Like I said, people can "say" whatever they want to make you think that they know something you dont, but the fact is, the ECM will either report the correct data, or nothing at all.

But then again, this is the internet afterall so its not like I can truly prove anyone right or wrong.

The xtreme was the hottest available tune for the LB7 at the time that EFILive came out. Obviously the tune cant be directly 'read out' because the ECM's were/are locked. But how do you think we got an idea of "what constitutes a 'really hot' tune"? You data log it... any log of an LB7 xtreme will show you the real pulse width and timing is...and if you took a billion different logs at all different driving conditions, you could probably reverse engineer 90% of the Xtreme tune. Of course steve isnt going to concede this is actually possible!! Duh! Why would he????? He (and anyone else who writes locked tunes) is going to say "nope, whatever you log is 'fooled' because of magic trickery in the ECM" to make you think "oh crap...my plan of copying/reverse engineering the tune via logging isnt gonna work...I guess ill give up"....and voila, the white lie worked. Brilliant!

 

[MMLMM]

Wait...so now logging actual data the ECM/TCM uses to make its OWN adjustments may be incorrect (in a certian ECM)..:rofl:

Ill believe the log before I believe something someone saw and has no idea how or what he saw someone do at someones shop sometime...

I know you cant just copy a lg and run with it..There are far more adjustment that need to be made in a tune and that is too much data to log at once...However, with the amount of data we can log, I can bet on it weather its a locked/unlocked/factory/custom/superdooper ECM we can damn near hit it pretty close. The scan tool or whatever you may be using is only monitoring what the ECM/TCM is telling the truck to do. If you are seeing something flawed, then the truck is not running right...Hence why the tech II and scan devices are considered a diag tool....

 

[duratothemax]

Driveability is difficult to reverse engineer via logging because of the infinite level (well, almost) of possible values etc... But "theoretically" if I wanted to make the same hp curve as a Kennedy tune (just using that as an example of a locked tune) from say 1500 rpm to 4500 rpm, all I have to do is make a bunch of WOT 1500-4500rpm passes on a flat, level straight stretch of road, review the log, and spend many hours reproducing the curve of the maps in efilive as deduced from the log.

No one can tell me "oh that wont work"...

Like I said, at anything less than WOT under controlled conditions, its much more difficult and tedious to reverse engineer it this way, but its technically not impossible by any means. All locking the ECM does is make it much much more difficult to "get" the tune and reproduce it/see what the tuner did [in efilive]. It doesnt make it impossible...

JMO.

Ben

 

[MMLMM]

Oh and another thing...locking ECMs....Remember that the factory ECM is locked and EFI provided a crack....

Put EFI aside (as its an example), and realize, no locked ECM out there is really locked....

 

[sweetdiesel]

Op should of never mentioned tts:rofl:

I'm with Ben on the locked ECM but who cares! Steves tunes are nothing special
no one can tune your truck better than being in the truck and custom tuning it !

That why efi is so good! To bad people don't take the time to realize that

 

[sweetdiesel]

Btw general posted great info!

 

[redws6rocket]

alright, i was hoping for some more tuning help! i don't care, and i don't to argue about a locked pcm, i just want some more tuning help from you guys. i in no way shape and form want to copy steve's tunes, my computer has about 8 logs from pulls that i made when i ran his pcm in my old red truck, i just refer back to them at times.

rob thank you, what you said helped alot. i would like to bring a truck up and put it on the dyno sometime and see what changes some numbers around really does!

 

[IOWA LLY]

What are some of the specs on what you are tuning? Mainly injector size, camshaft rpm range, and turbo size....