HPTuners SCAN LINKY
Location in scan, frame 15,477.

Scan of a 2003 SS, 65E, 6.0(all stock) radix with 2.8 pulley.

The person is riding along at 37%TPS and goes foot to floor. If I move my mouse over the graph and watch the table display the injectors goes 21.x mseconds as soon as he floors it but the % of IDC climbs slowly? WTF? The wideband reads rich enough, (you have to add .2 to .3 to his wideband for ground offset error...yeah I know ) besides the huge lean tip in, everything seems to go as it should, AFR recovers almost instantly, but the KR and the IDC % are wild.

It unlocks the converter, shifts down, hmmm. There's alot of things in that spot on that scan that gets me actually now that I think about it.

If PE enrichment rate is supposed to be BAM now (his is set at 4), then why does it take the time to go to 12.5AFR commanded when he nails it? The Injector pulse goes to 19.5, then once it goes to AFR commanded 11.6 the Injector pulse goes to 21.1. What a ball buster, that extra fuel on a radix setup would be nice. Even if it is a milisecond. Seems the PCM goes PE first then BE. MAP reading at 12.5 commanded is 120kpa, theoretically it should be referencing the BE table at this point. Which in his tune is 11.95AFR commanded.

I understand that 80+mph and blasting it to 110+ is alot of load(cylinder pressure is right on the edge, so lots of kr with a hard blip of the throttle makes sense to me), even in 3rd gear, so kr makes sense, escpecially with the lean tip in....but notice the afr as he gets ready to get out of it, it goes too rich.

My take on this...same as always, we need more room on these PCM's so that we can have a TPS modifier for the VE table. LOL

 

FWIW injector PW & IDC will never run parallel to each other...IDC is calculate from pulse width but the PW wont represent IDC.

 

I sorta understand, I was just thinking in this scenario...knowing with his sized injectors and his setup, they should be maxed, or you'd think so. And in 3rd gear, flooring it at 80mph at 2600rpm to 116mph at 5600rpm in 6.xsecs, I would think they would max pretty quick, lots of load/weight there. I was just trying to use the IDC as reference for the kr problem, again knowing his setup has maxed the injectors for awhile now.

I guess I could compare a 1/4 mile run where he is in that same gear and rpm range to see what his IDC is.

Long story short, more fuel in that tip in would help IMO, but I wouldn't want that same amount of fuel once initial tip in was done. Anybody have any ideas besides a TPS modifier?

 

anything over 80% is considered static so they are maxed.

 

so, can I assume that since they are maxed, the same amount fuel is going into the cylinders once they hit 21msec at the beginning of the "blast" to the end of the "blast". If that's assumable, why the slow AFR decrease rate? get's richer and richer. It stays in the 160KPA row on the ve table, it in fact climbs a few points in kpa (but stays in the 160kpa row), so I don't see belt slip. The value in the ve table in those cells are the same. This scan would be telling me to decrease the value in cell 160kpa/5600RPM by whatever % difference in the afr values. About 2-3%. How could 160kpa/5600rpm be a lesser value than 160/5200rpm, or 160/4800?

To be honest I see this in a few radix tunes, where at the peak of the boost it sorta drops in fueling needs by 1-3%. why? is this a blower effiency thing, especially considering the 2.8 pulley?

 

thing is it does go a bit rich...if a few % of fuel were taken out you might be able to get it down under 85% IDC...guess you'd have to just play with it.

 

wow that guys tune is a mess! who's the idiot that did that tune?

 

Static = constantly open = 100%.

Anything over 80% puts the injectors at risk of overheating, but does not mean they're static. If that was the case, you'd see AFRs go progressively leaner as IDC increased over 80%...

 

Just going by what I've read

http://www.rbracing-rsr.com/calcinjpulse.html
"Beyond the 85% figure horsepower can actually drop as the pintles or discs in the injectors are essentially "floating". At this point the injectors actually put out less fuel until they are fully pulsed static and then the final output goes to 90% of their rated capacity. Injectors should not be pulsed beyond an 85% duty cycle."

Maybe the term static I used is incorrect...but most recommend staying in the 70-80% range.

http://www.precisionturbo.net/techinfotext.php?aid=11

 

I saw this constantly on my 5.3 when I had the stock 24# injectors the faster Id go the more IDC went up and the leaner it got.

Dew:
Id make sure all the other factors that have to be met for PE enable are where they should be, if it still gives problems log the multiplier and compare it too the pe table to make sure other factors arent commin into play. If the multiplier is some other value than whats in the pe table then you know what too look for.