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Tuning 60 pound injectors

an exhaust leak would make your fuel trims lean, like +16.

I don't worry about my stft's. even ltft's can be ignored sometimes, like when in deceleration enleanment.

I would often start a scan right after I reset my fuel trims because they would go to 0, and then when they relearned, the actual number would replace the 0.

also, I never set my PE to 100% because I wanted the data from wot runs, I just never went wot until I had everything with 5% of 0.

edit for additional info: You NEED to add Cylinder Airmass to your graph and/or to your channels so you can get accurate data on timing advance and knock retard.

I'm not sure if you need to be scanning for burst knock, I don't actually know if that was in the programming in 2004
 
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Crap well hopefully the leak is fixed. I'm confused on what to follow now. I am using the sticky thread "starting HPTuners" for this. I have also seen the other sticky do the maf disable VE method.
I will set the PE back to where it was. Should I reset and use the relearn again or just scan and do the adjustment I am following in "starting HPtuners"?

** per the cylinder air mass graph, how do I set that up??
 
I would keep using the "starting HP Tuners" thread, I just didn't bother changing the tune to only have PE enabled at 100% throttle. I'm just not comfortable enough to be on the road driving and not have the power enrichment option.

To add cylinder airmass, scroll your mouse over to the left side of the scanner and open the channels display. right click on an empty box and select add channel. when the page opens, at the top there will be an empty box where you can type, type in cylinder airmass and double click the top one, it should say something like "this is a generic sensor, would you like to continue?" you want the generic sensor.

on your graph, where it says timing advance and knock retard, all you need to do is right click one of them to open the graph in edit mode, then left click the parameter that says cylinder airmass, and re add it making sure it is a generic sensor for cylinder airmass. do the same thing for both timing and kr.

edit: I would keep resetting and having your fuel trims relearn every time you change your maf airflow table, and don't bother disabling the maf to tune the VE because it's just a backup for the maf and has very little effect on how your engine runs when the maf is working like it should.

here is a guide for you on HP Tuners forum:

http://www.hptuners.com/forum/showt...AF-Fuel-Trim-Graph-in-VCM-Scanner-V3&p=419231
 
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My advance graph shows maf cylinder air mass is that the correct one.
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That guide you posted was for the LTFT+STFT I believe that I already followed that one here.
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If you have screenshots of your graph setup you wouldn't mind sharing that would help to see what you are talking about. I greatly appreciate your help.

For some reason photobucket is acting up right now so I cant post the other pics I wanted to.
 

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Fivefingerdeathpunch said:
Did you change your stoich to match the fuel you are running?

Are you watching your wideband to confim it's lean?

You also better off switching to lambda and not using AFR when tuning with E85.
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Changing stoich isn't as simple as changing the number in this box is it? I wouldn't think so but worth asking.
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I'm inserting a plug for the GM tuning guide DVDs I have in the for sale section by Greg Banish. No they will not tell you exactly what to change in our PCMs it is more geared to Gen3 V8s. But the basic tuning concept that Greg discusses is the same regardless of platform or engine management, it is still governed to the laws of physics.

If you not sure who Greg Banish is, then look him up. He is an engineer with a long background in OEM and aftermarket calibration.
 
Yes changing stoich is as simple as that. You don't have to change the stoich if you don't want too. Just start tuning with the MAF vs LTFT to correct the fueling.

Not to hate but those tuning DVD's are beyond over priced, I bought the first one used for $100 bucks years ago, turned around and sold it right away because the information is meh at best to me. You can get the same info from a book or just reading forums. Maybe if someone didn't a have darn clue about anything car related they might be helpful but for $250 new, LOL screw that.
 
Fivefingerdeathpunch said:
Yes changing stoich is as simple as that. You don't have to change the stoich if you don't want too. Just start tuning with the MAF vs LTFT to correct the fueling.

Not to hate but those tuning DVD's are beyond over priced, I bought the first one used for $100 bucks years ago, turned around and sold it right away because the information is meh at best to me. You can get the same info from a book or just reading forums. Maybe if someone didn't a have darn clue about anything car related they might be helpful but for $250 new, LOL screw that.
Click to expand...
Yep, the forums have armchair engineers and self-proclaimed experts aplenty.
 
I bought the advanced tuning book from Banish. It has great information but not specific to HPT or W body. It helps understand how the systems work. I think the HPT specific class from tuningschool.com would be the most beneficial but at $500 for the at home or online and $1000 for the two day class I won't have that kind of money.

Ok I will leave stoich as is for now. I will start scanning and adjusting with my LTFT graph and when I get it close the STFT+LTFT math option. Hopefully my graphs are set up properly. If someone would check those two to be sure that would be great. I don't want to scan and change with the wrong parameters.
 


I learned more from that book and reading forums than I ever did watching those video's.

If you setup the LTFT graph like I said a page back or two, it's right and will work.
 
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Originally Posted by Fivefingerdeathpunch
Yes changing stoich is as simple as that. You don't have to change the stoich if you don't want too. Just start tuning with the MAF vs LTFT to correct the fueling.

Not to hate but those tuning DVD's are beyond over priced, I bought the first one used for $100 bucks years ago, turned around and sold it right away because the information is meh at best to me. You can get the same info from a book or just reading forums. Maybe if someone didn't a have darn clue about anything car related they might be helpful but for $250 new, LOL screw that.



Yep, the forums have armchair engineers and self-proclaimed experts aplenty.

says the guy who has made very few suggestions on this tuning thread
 
Well looks like from here it is best to have a wideband. Is there anything I can safely adjust from here without a wideband?? It will probably be a while before I can pick one up.
 


GTPpower said:
If you have kr at wot, you can add more fuel to see if it clears up. That's really about it.
Click to expand...

ok thanks, I will check. I probably went a little small on the pulley right off the bat. I went with a 3.0. I did however pickup a 3.2 also just in case I have to swap it out. I just have to pick up a belt for it. Is there a write up on how to add the fuel if I have knock?
 
you should be running a 2.8 pulley and 21º wot timing with no issues at all.

i helped out a guy in NC 40thanngtp iirc with his tune. he was on corn 80's, 1.95 yt rockers, gen 5 blower, 2.6 pulley, full size ic set up cause he had it before the e85 swap and kept it on there, making around 16 psi till he blew a head gasket.

now hes got ported heads, and a cam with the ic. same tune pretty much, no kr still and last he told me he was at 22 wot timing. hes beating ls cars with bolt on's. hes also got the just in case button, a 75 shot. no kr when the juice is on either. hes also got a huge ass fuel pump. the nos was demanding more fuel then the stock pump could give, or even the most common corn up grade pump out there. and a pump rewire of course.
 
The MAF controls fueling.

That is why you have been tuning your fuel trims to correct the fueling. By removing or adding to the MAF curve you are telling it to remove or add fuel. At WOT you'd be adjusting the curve much higher up, like above 7,500hz on the scale.

You set a commanded AFR during PE, so like 11.5 AFR for example. If you did a run and you saw 11.7 you would then add 1-2% worth of fuel to the curve above like 7,500 to bring the AFR down to match the commanded AFR. You can change the commaded AFR if you want to run richer, so switching it to 11.0. Then again you would log it and see how close you are to that commanded number. Being within 1-3% of the commanded is pretty darn good.
 
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