LS1/LS2/LS3/LS4/LS7 etc. - LOGGING, ADJUSTING INJECTOR SLOPE

jsk06c6 · Post by **jsk06c6** » Sun Oct 14, 2007 12:26 am

06MonteSS wrote:get as much as you can... it's better for getting the ltft's figured out and dialed in... he was just saying you COULD use it if it was only 30 seconds... but you want to log as long as you can... more data points gives us better info on what adjustments to make...

To be honest, it aint easy. My LTFT's are all over the place. They do seem to be more where I expect them to be on long upgrades. Of course I really think the problem is how short the log ability is with the 7194. Today I was playing around driving to get the numbers in, and I must have run 10 logs holding the unit looking at the numbers. I've yet to get the same numbers in any log, the time is just too short for it to settle in. For example, in a minute and a half after drving at 61mph for 5 minutes the LTFT's went from .8/ 5.4 to -1.5/0 to 4.6/.8 to the 0/.8 I really was expecting. All of this in 45 seconds actually, in cruise, in pretty level driving. Tuff to figure out which number is right.

Post by **06MonteSS** » Sun Oct 14, 2007 8:53 am

yeah, that's why people with laptops have it easier... you can run the laptop in your car and log as long as you want with the Dataviewer directly...

jsk06c6 · Post by **jsk06c6** » Sun Oct 14, 2007 10:12 am

06MonteSS wrote:yeah, that's why people with laptops have it easier... you can run the laptop in your car and log as long as you want with the Dataviewer directly...

I found a car adapter for my dead battery laptop on ebay, so I'll give it a try next weekend. Thanks for the suggestion.

Post by **06MonteSS** » Sun Oct 14, 2007 11:41 am

np... yeah, you hook the predator up to the OBD port... then connect it to your laptop via the serial cable... then on the laptop, start up the Dataviewer app... then in the Dataviewer (not the predator), you select the parameters you want to log... click the Record button in the top menu and away you go! then just click the Stop button when you've had enough...

tip: don't make it too long though... cuz MS Excel will still only load up to 65,5xx lines of data anyway... and by using the laptop, you actually get better logs - more data - cuz the sampling rate is much quicker, so it won't take long to get to that 65,5xx lines of data... probably about 10 minutes of log time will fill that up... if that much...

jsk06c6 · Post by **jsk06c6** » Sun Oct 14, 2007 3:31 pm

06MonteSS wrote:np... yeah, you hook the predator up to the OBD port... then connect it to your laptop via the serial cable... then on the laptop, start up the Dataviewer app... then in the Dataviewer (not the predator), you select the parameters you want to log... click the Record button in the top menu and away you go! then just click the Stop button when you've had enough...

tip: don't make it too long though... cuz MS Excel will still only load up to 65,5xx lines of data anyway... and by using the laptop, you actually get better logs - more data - cuz the sampling rate is much quicker, so it won't take long to get to that 65,5xx lines of data... probably about 10 minutes of log time will fill that up... if that much...

Thanks, I drove quite a bit today in cruise, just monitoring the data, I think it gave me what I need, got to take out another -1 on the slope and do it again next week. I should have the laptop running by then.

07SD · Post by **07SD** » Tue Oct 16, 2007 12:40 pm

I have a 07 Seirra Denali and using my u7194 for my first log, I got a LTFT of 2.344. I did not have to average because all my readings were 2.344 for the entire log.

I was on a level road with the crusie control set; then I started the log. I was surprised that the LTFT remained constant. AFR remained at 14.75 and RPM varied 53 RPM's. Colud I have done something wrong?

jsk06c6 · Post by **jsk06c6** » Tue Oct 16, 2007 12:47 pm

07SD wrote:I have a 07 Seirra Denali and using my u7194 for my first log, I got a LTFT of 2.344. I did not have to average because all my readings were 2.344 for the entire log.

I was on a level road with the crusie control set; then I started the log. I was surprised that the LTFT remained constant. AFR remained at 14.75 and RPM varied 53 RPM's. Colud I have done something wrong?

Probably not, but I'd run another log to verify.

07SD · Post by **07SD** » Wed Oct 17, 2007 1:07 pm

jsk06c6 wrote:
07SD wrote:I have a 07 Seirra Denali and using my u7194 for my first log, I got a LTFT of 2.344. I did not have to average because all my readings were 2.344 for the entire log.

I was on a level road with the crusie control set; then I started the log. I was surprised that the LTFT remained constant. AFR remained at 14.75 and RPM varied 53 RPM's. Colud I have done something wrong?
Probably not, but I'd run another log to verify.

I set my LTFT and ran another log, this time using my laptop. The LTFT for bank 1 is avg ~.8 but since I was using a laptop I get a bank 2 reading of
minus ~.8. Is this normal?

By-the-way a laptop is the way to go with logiging!

Post by **06MonteSS** » Wed Oct 17, 2007 2:18 pm

yeah, the won't both be exactly the same... you're fine...

DOA · Post by **DOA** » Sat Oct 20, 2007 5:13 pm

I have a u7194 and an 07 Chevy Avalanche, how do I turn off DOD so I can start logging?

Thanks

Lance

Post by **06MonteSS** » Sun Oct 21, 2007 10:59 am

I don't think you can disable the DOD on your truck yet... they should have an update in the future that will allow you to. so just go ahead and do a log.

DOA · Post by **DOA** » Sun Oct 21, 2007 12:24 pm

Bummer. It looks like my Long Term Slopes are all over when the V4 kicks in.

Thanks

Lance

Post by **06MonteSS** » Sun Oct 21, 2007 2:34 pm

yeah, they will be... try to find a long stretch up a hill... you should be able to keep 25% throttle position all the way up the hill and the DOD won't kick on, since there will be a load on the engine...

TheGoat · Post by **TheGoat** » Sat Oct 27, 2007 3:10 pm

Ok I am new to this so adding PE means adding fuel at wide open throttle right? What gear should I log my Lfts for my six speed LS2 GTO?

Post by **06MonteSS** » Sat Oct 27, 2007 6:52 pm

yes, going positive in PE adds fuel at WOT, making you richer and lowering your AFR.

the injector slope for normal driving/cruising ltft's works the opposite - positive slope makes you leaner, and negative slope makes you richer...

do your normal driving/cruising log in 4th or 5th gear.

for WOT runs, start in the lowest gear you can and go through the gears. if you just have it in 5th for instance, and just floor it, you're gonna get a bunch of KR... so this is why we need to start low and do the WOT run by going through all the gears, or at least as many as you can