Im just playing devils advocate but they could have used different materials during that time and also I would think harmonic frequencies between a small block and a big block would be different there is more material to travel through. Id be interested to see if the knock sensors are different or the same, if they are tuned to a different frequency then thats the answer.

Are you saying the filter is 4.7 on one year of 8.1 and different on other years?

Whats the word on the race gas?

 

Yes, i have two other 8.1L tunes, both are stock tunes, one is a 2002 and one is a 2004. You can download both of them from the EFIholden site. Both of those tunes are set at 4.70. I can only assume my old tuner adjusted this field for some reason and thats why its different. I should be getting the race gas (CAM2) tonight.

 

I understand your position, and it's a good one to bring up that makes sense. Forces me to do more homework on the subject.

Like Jimmie just said, 2002 8.1L at 4.7, his 2003 at 7.9 (this is actually suspect IMO), and a 2004 8.1L at 4.7. I say that his is suspect because I think it may actually be an out of range value. Every time I've tried to load up his tunes, I get an out of range error and the file defaults it to 7.9. Thinking that if his tuner was using Edit or something that didn't limit his values to the specified 4 for that table, then the PCM would have been freaking out over this unexpected value, and possibly not filtering anything at all...

 

Okay boys here we go. First run was with the new sensor filter set at 4.70. I saw improvement in the log, seemed like quite a bit of improvement. Still logged more KR than i should have however. Second run was with the CAM2 (110 octane). I let the gas go almost all the way down, it was on the line but the gas light was not on, so i figure there was no more than 3 gallons in there. I put 10 gallons (@ $6.15 per gallon ) in there and ran around for about 10 minutes or so to let the gas mix up and saturate into the tank. Here is the wierd part, no other changes were made and i saw more KR with the CAM2 than with the 93 gas... . I logged both runs for about 18 minutes so a good comparison can be done. I noticed a few things with the CAM2, i ran much richer when in boost, and that stuff smells so sweet! I tried to duplicate similar situations, I.E. same RPM, same MPH, same gear, etc......to see if similar things took place and they did NOT. Seems wierd that i can be rolling along at 40mph, hit the gas part throttle and hit 3.5* of KR. Then when i do it again, everything is the same, and i get none. So i am on the fence here....i am thinking this KR i am seeing has got to be 90% false, but i need someone ALOT smarter and more confident than me to agree with me. Also, how do i tune this thing if i seem to be getting false KR popping up? Its going to retard my timing when i dont want it to, and unjustifiably so. There was one pull in the CAM2 log at frames 1918 -1942, where i nailed it at about 62mph and got 0* KR and the timing stayed at 14* and it felt so sweet! It pulled like a monster, i didnt even have to look down to know it was not retarding any.

The VE table still looks a little suspect to me in places, and i tried smoothing out that dip but it made no difference. I am noticing large spikes in my real AFR after WOT, sometimes as high as 20...thats not good is it? Okay, so let me post up these logs for anyone to have a gander at and see what they think. They are named accordingly......i patiently await your feedback.

http://www.pasadenatownhall.com/tunes.zip

 

perhaps i need to look into the burst knock areas? I am confused now on what to do. Maybe it has to do with something with the Allison pulling timing from someplace? Maybe i need to start testing in the torque limiting areas of the traction control section like Trippin said over at the diesel place? Dont really know what to do now.

 

you got two really good troubleshooters here with ya, 02sierra and dc, but it's not hard to do a search on here to find out quickly I am not for burst knock and FI. It completely defeats the purpose of FI characteristics IMO. BUT, BUT...BUT LOL burst doesn't show as kr, it just removes the timing, at least with hpt. You have to choose the pid for it to see it. Loooong story short, I zero'ed my burst knock a long time ago, but at least in hpt, kr is not burst knock, you have to specifically log burst.

How rich is too rich?

Not sure about big blocks, but there is a such thing as rich knock.

Lean spikes without your foot on the throttle is fine. As long as you aren't intending to try to make the beast move (read as accelerate) more or in boost. Most occasions tuning your ve table will help with lean spikes in areas that aren't to much of concern here (here being this topic thread)

which tune are you running from that last zip file?

increase the kr recovery rate. Your knock hangs too long. do it, DO IT!

 

I don't see in the updated spark tune that frequency stayed 4.7. I am looking at 7.9. It does show the option to lower, but if you changed it and saved the file and the file I am looking at is that file, it didn't take and I'd conclude with everybody else...you are to sensitive...you being the knock sensors.

jim i am not sold on the tm and trans stuff, why would you see kr if that was the case? it would be in some form of tm "advance", not actual reporting from the knock sensors.

 

hey justin (or any efi guy)

so for example, on the spark table, I want to put the rpm on the x axis and the g/cyl on the y axis, how do i swap them. ANd how do you convert/conversions the temp stuff, like ECT celcius to Far?

 

I updated the zip in my last post to include the tune file i am using now. It shows the correct values in the sensor filter table.

Your absolutely right DEW, i didnt think about it that way. If the Allison were going to pull timing based on RPM,Gear, or whatever, it surely would not show in the log as KR....good point.

 

just in case you didn't hear me...