Mat

Right on! I'll give a dealship I know a call on Monday and see what they can do for me! Thanks man!

Crash Dummy

981 MV on the sensors is by far not lean its more like pig rich at matter of fact it looks like its pig rich everywere. This is the stock factory tune ??

Another_User

981mv...very likely pig rich. I run mine at 890mv on one, 915mv on the other...stupid O2 sensors. And no, it is not a problem with the sensors. That is just how it is in my car.

Mat

Yeah the exhaust reeks now too.. it has ever since I installed the longtubes.. in some places (and I can send you logs) I've got O2 voltages in the 1011 range etc. at WOT around 5800 to 6100 rpm... My pulse widths are sitting at 19.5 and 19.6 in some places too! I have no idea what's going on here..

Best guess so far is that since my car is still in SD mode since I'm finishing up VE tuning maybe that is the cause of it? My friend Mark's 99 LS1 has completed VE tuning, recaled the MAF using redhardsupra's sheet, and his car is also behaving strangely.. His pulse widths are also 18 to 19 (100 to 115% duty cycle)...

Anyhow... I've had times now where I got the knock and where I didn't. I'll post the some screen shots and a log (in .csv format) tomorrow when I get home from work. The car feels down on power too.. for a set of longtubes/Y-pipe that guys see 18 to 30 rwhp from it sure doesn't feel like it. I'm guessing this is because it's pig rich right now? Please tell me I'm right! Can I do some basic PE tuning and lean it out to get the O2's down to the 900 range like they should be?

Thanks for ALL the help guys! Big time appreciated here!!

Crash Dummy

It looks like the tune needs some major adjusting I just bought the 2 bar HP tuners SD tune but have not had any time to start messing with it so I am going to have to say that I can not be alot of help helping you with your tune but I am sure someone will jump in and help you. Sorry!

SmokingWS6

iTrader: (1)

Holy richness batman, I'm use to 880mv or so at wot. How do your LTFT's look? I'm assuming they are pegged negative?

Also, the 7 y/o fuel filter can't be good anymore, I have 40k but I still replace my filter every spring.

MNR-0

If its a stock WS6 then you have too much timing. Should take anywhere from 20-22* tops. You are also running FAT-AS! Try tuning your narrowband to 940mv and see some power.

Mat

My LTFT's sat at around +16's to +20's with the MAF plugged in and before I messed with my tune at all in Speed Density.

After tuning the VE tables in speed density I've got all my LTFT's sitting between -5 and +2 with majority of them being 0's then -1's and +1's.... I would also expect to see big time negatives across the board instead of what I do see!

I looked at a log BEFORE I started messing with the car at all, right after I installed the longtubes and it made more sense. I had O2's reading in the 940's (makes since since they should be rich after the headers) and pulse widths reading 16's or so (much better then 19's and 20's!).

Buddy of mine just apply'ed a leaned out PE table to his car and dropped his O2's from 940's to 900's and 920's or so.. Thus I think this is what I need to do as well. However!

First I'm going to finish my SD Tune and recalibrate my MAF using redhardsupra's sheet.

Then I'll change my fuel filter!

Finally, I'll take a good look at the PE table and scale it back by the same margin he did with his. See where I'm at. Then scale it back a little more. I'm going to book some time on a dyno with a wideband so I can really "dial" it in safely but if I can get my 02's at least down into the 910's or so I'll be much happier and my exhaust won't smell like my fathers 1965 Olds 425 race motor!

Thanks for the reply man! Hopefully we can keep the thread rolling!

Mat

Really? Well the car has longtubes, 3" catted Y, exhaust, and a lid on it right now. I've always heard that LS1's love 28* of timing or around there. I know the 98's have a more "aggressive" timing table though hence another reason why we get more knock problems. Is that about what you run through yours for timing?

Oh yes, I know I'm running big time FAT... I'm going to lean out the PE table after I finish my SD stuff and see what I can get my O2's down too. Just like you said I'll shoot for lower 900's without getting too crazy. I need a wideband to do it accurately I suppose!

My car does feel like a dog right now.. definately not like it should feel with a set of longtubes on it. I can't wait to get this fixed up!

Any more help/suggestions/idea's? Thanks guys!

WicketMike

iTrader: (13)

if you havent changed your knock sensors, you need to. there is a TSB out on them.

when you change them, you wont believe how hard the rubber is, it will be hard as a rock. when you change them, you need to put some silicone around them, so water doesnt get back in there.

SmokingWS6

iTrader: (1)

I'd have to disagree, I have had good results with 26* at mid range and 28* up top. This is also combined with corrected afr.

Mat, It could be a long shot but I've heard extreme richness causes KR(probably false due to richness missfires). Also, don't tune untill the filter has been replaced, if its restricting flow in any way it'll throw off your tune once its replaced.

cz2898

just got hp tuners also and 4degs on the hard runs also. im new to this tuning and the reason i got hptuners was to pass emissions becuase my hc's and nox. what do you guys reccomend to get the a/f to and should i retard the timing at all?

Mat

Yep good call. I think I'll replace the fuel filter today when I'm done work. Then maybe I'll finish my MAF Cal on the car.

I've got a new leaned out PE table that my buddy is using in his 99 Hawk and is working quite well for him. I might need to go more then what it is, but in the very least, it's going to be FAR better then where I am now.

The new PE table was graciously provided by a very knowledgable fellow. That I'll throw in the car after I finish a good solid MAF Cal.

I'm lovin' this tuning stuff! I'm learning an insane amount of things right now. Having computers as my background and guys like all of you responding to my posts is helping me out immensely! Thanks!!

I'm going to keep this thread rolling as I make progress on these issues so it will hopefully benefit others if they do a search and come across it!

Mat

For sure. I'm going to fix the car up with it's tune, and as soon as the tune is done if I've still got KR sitting around (and I bet I will) then I'm doing the knock TSB right away.

Thanks for the tip man!

Mat

Post up a screen shot like I did of your Retard Tab, your Advance Tab etc. from one of your scanning session histograms for us to have a look at.

If you don't have a wideband your essentially estimating by using the 02 voltages you'll have returned to you in your VCM scanning sessions. People generally look for 890 to 900 millivolts as a good value. The lower the number the leaner the car is, the higher the number the more rich the car is. Some people say that you can get the car very close by using the narrowband 02 sensor tuning method (what you can do now), others say that you need a wideband 02 sensor to really get an accurate reading (what you would either buy and install or get on a dyno that is equiped with one).

I think the recommended target AFR is around 12.8 or so for power production? Correct me if I'm wrong. Not sure if that's the best choice for emissions or not?

Hope that helps!

RedHardSupra

iTrader: (1)

ve first, maf second, or if you know what you're doing, both at the same time. then pe/timing is kinda a tricky combo, as one affects the other.

pe settings are very hotly disputed, so don't expect any clean answers.
some will say 13.3(lowrpm)-13.0(highrpm), others will say 12.6 all around (and i find it to be the most universal setting, but not the 'max effort.'
i set it up 13.0 until peak torque, then i keep going lower until about 12.2. it seems to work well, you've seen Mark's PE table, you know what i'm talking about
do not use narrowband o2s to figure out anything. someone did a little study and prove that the error margin of stock o2s is bigger than the precision needed, so the whole thing is pretty useless. use the commanded pe tables, use the narrowband as a guide and a heuristic, but eventually you'll want to verify that with a wideband.

Mat

Many thanks! Yes Mark and I have been working together and making some great progress! Thanks big time for the help too. I owe you beer.

I finished a solid MAF cal today.. gotta still hand smooth the parts below 2100 and above 9500 as I didn't get any readings (per the norm I suppose). That will be an ongoing process at any rate using your kick *** spreadsheet tool.

After that, I loaded in Mark's PE table and even though the car is still learning it's way out of the low octane tables, it's made a noticible difference. My O2's have dropped to reading 959 and 939 at 6000 rpm WOT. My SAE MAF is cresting 38.13 at the same RPM and my MAP seems to hover in the mid 90's across the board in the upper rpms.

I saw 0 degree's of knock retard there at 6000 too but there again I only had 22.5 degrees of ignition timing. The car needs some miles on it, then once it's good and learned, it'll be fun time.

Think I should scale the PE any more because of the headers? I'm more apt to err on the side of caution as you mention. The Narrowbands aren't the greatest and when they are futher downstream that affects them even more.

Thanks man! I'll post up some screenshots of my histograms now after my VE tune and my new PE table modifications.