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critter
September 17th, 2007, 06:31 AM
I ditched the MAF for this season, and belive I have the PCM more or less set for OLSD. This is not a car I can drive around and and do the AutoVE thing. If I grok this stuff correctly, if I don't want surprises, I must set {B3605} lean and tune with {B3618} or, if more brave, set {B3618} lean and tune with {B3605}. Am I close?

joecar
September 17th, 2007, 06:53 AM
Hi Critter,

B3618 is enabled by B3616, BB3613, B3610, B3608, and a few others (read each's desscription carefully).

When B3618 is enabled, the PCM chooses the richer of B3618 and B3605; this is reflected in the PCM's commanded AFR; so you can tune with either or both.

I like to set my B3605 for cruising (except from > 70 kPa I ramp it up sharply), and then I fine tune my B3618 for torque/power, and I also fine tune B3616 and B3613 (i.e. when PE is enabled).

Cheers,
Joe

critter
September 17th, 2007, 07:43 AM
Thanks Joe. I wasn't very clear - too many balls in the air at the moment (chasing a memory leak).

My car is a race car, and it seemed to me that as I start leaning it down looking for MPH that when it switches from the PE table to the OLFA table I will be scratching my head over why the WBO2 reading doesn't change as I lean it down. Thus it seemed to make sense to get one table out of the way and use the other. Make sense?

joecar
September 17th, 2007, 09:21 AM
Ooops... I mistyped... see B3616 above... sorry.

B3616 is TP vs RPM enabler for PE; check this table for when PE is enabled/disabled (TP must be above curve at a given RPM's).

Check the other enablers: B3608, B3610, B3611, B3612, B3613.

Or, if it's a racecar, then set the PE table to EQ 1.00 across and just tune the OLFA table.

Post pics of:
- B3605
- B3618
- the table containing B3608, B3610, B3611, B3612, B3613, etc.

What car do you have...?

lol... memory leaks... I've chased quite a few of those... :D

joecar
September 17th, 2007, 09:26 AM
Post some logs or pics of log charts showing commanded AFR and actual AFR.

critter
September 17th, 2007, 01:18 PM
Ooops... I mistyped... see B3616 above... sorry.

No sweat. I can cope :-)


B3616 is TP vs RPM enabler for PE; check this table for when PE is enabled/disabled (TP must be above curve at a given RPM's).

It is stock 2K, I think - ahything over 20% above 4400.


Check the other enablers: B3608, B3610, B3611, B3612, B3613.

0, 0, -40, 284, 15 respectively.


Or, if it's a racecar, then set the PE table to EQ 1.00 across and just tune the OLFA table.

Yeah, that is what I was thinking - put one or the other out of reach and tune with only one. I don't know which is easier, PE or OLFA.


Post pics of:
- B3605
- B3618
- the table containing B3608, B3610, B3611, B3612, B3613, etc.

Upload didn't go so well, so here are a couple of links:
http://critter.syscon-intl.com/picture1.png
http://critter.syscon-intl.com/picture2.png
B3605 looks stock, and I think all munging in the past has been on B3618, which is currently set for something I hope is safe.


Post some logs or pics of log charts showing commanded AFR and actual AFR.

I don't have anything current. The car is just finally back together and I have been working on moving from a 2000 OS to 2002 with the intention of going COS, but time is running out.


What car do you have...?

It is a 2000 Z28, iron 6L, face plated Tremec TK600, FAST, etc. I have had really lousy luck with this thing. I lost an LPE motor (I won't tell you how much ...) at the LS1 meet at Bowling Green a couple years ago. I bought a 6L short block and only got some breakin on the street and a few passes before the rod bearings failed due to the pistons kissing the heads. Yes, I used the gasket the builder spec'ed :-( It went 10.32 at 132 as the motor was coming apart. I am looking for 9s on motor this year.


lol... memory leaks... I've chased quite a few of those... :D
This is mmaping and munmapping shared memory on Linux. Really weird.

joecar
September 18th, 2007, 03:18 AM
B3605 Suggestions:
- set the last 3 cols to AFR 12.6;
- set rows 212-230 cols 20-50 to 14.7;
- set rows 68-86 cols 20-45 to blend in;

You don't want to go lean anywhere, and you want to be sufficiently rich under load;

I just remembered that the PE table allows you to fine tune AFR as RPM sweeps from torque peak to power peak (whereas OLFA is MAP vs temp)... in this case, if you go this way, set OLFA table to be safe: set its last 3 cols to the same AFR as the leanest AFR in the PE table (which should be at least richer than 13.2-12.7)... Then whenever the PE table commands richer than the OLFA table, the PCM just selects the richer.

If it's ok with you, post your tune file.

People have found by experiment that peak torque likes AFR ~12.6-12.8 and peak power likes ~12.8-13.2; may want to search this out... but avoid going lean at all costs.

Remember to say "richer is numerically lower"... want to avoid easily made late-night-mistakes...

Linux is a fun/crazy DIY OS... :D

critter
September 18th, 2007, 06:44 AM
B3605 Suggestions:
- set the last 3 cols to AFR 12.6;
- set rows 212-230 cols 20-50 to 14.7;
- set rows 68-86 cols 20-45 to blend in;

You don't want to go lean anywhere, and you want to be sufficiently rich under load;

I just remembered that the PE table allows you to fine tune AFR as RPM sweeps from torque peak to power peak (whereas OLFA is MAP vs temp)... in this case, if you go this way, set OLFA table to be safe: set its last 3 cols to the same AFR as the leanest AFR in the PE table (which should be at least richer than 13.2-12.7)... Then whenever the PE table commands richer than the OLFA table, the PCM just selects the richer.

Understood.


If it's ok with you, post your tune file.

http://critter.syscon-intl.com/01_0000.tun

I see that reducing the size of the screen grabs fuzzed them up. Should have left them alone.


People have found by experiment that peak torque likes AFR ~12.6-12.8 and peak power likes ~12.8-13.2; may want to search this out... but avoid going lean at all costs.

Remember to say "richer is numerically lower"... want to avoid easily made late-night-mistakes...

Yeah, I have read that the LS1 likes to be leaner than 12.8 so planned to go leaner from there.

And I have made those mistakes. Fortunately, not fatal ... :-(


Linux is a fun/crazy DIY OS... :D
That it is! The twink that wrote the code did not free() after a scandir() :-(

joecar
September 18th, 2007, 06:47 AM
I'll view your tune file when I get home tonite.

joecar
September 19th, 2007, 03:50 AM
Hi,

I took the liberty to make some sugestions/changes to your tune, see attached;

In the rpm and temp bypasses, min/max/zero values may have special meaning (or they may not), so I like to put simple values like 400, 100, 100.

If you think B3605 is too rich, then lean it a little (keep it safe, not lean), but keep that general shape.
If you tune only B3605, then adjust the last 3 cols (and the slope of the transition).

If you also tune B3618, the rich part is wherever your peak torque RPM is at, and above that it leans a few fraction points to where peak power is (the end of the table).

Notice that you want B3616 to enable PE before you get to peak torque.

BTW: I set my tunetool properties fuel units to EQ, it avoids some other problems.

critter
September 19th, 2007, 04:03 AM
Hi,

I took the liberty to make some sugestions/changes to your tune, see attached;

In the rpm and temp bypasses, min/max/zero values may have special meaning (or they may not), so I like to put simple values like 400, 100, 100.

Thank you very much. I will diff the two.


If you think B3605 is too rich, then lean it a little (keep it safe, not lean), but keep that general shape.
If you tune only B3605, then adjust the last 3 cols (and the slope of the transition).

If you also tune B3618, the rich part is wherever your peak torque RPM is at, and above that it leans a few fraction points to where peak power is (the end of the table).

I haven't sorted out which I want to do yet. It wouldn't fire last night with the new PCM, so plans got sidetracked.


Notice that you want B3616 to enable PE before you get to peak torque.

Duly noted. I will make sure.


BTW: I set my tunetool properties fuel units to EQ, it avoids some other problems.

Having not worked on a tune much recently, I no longer have an intuitive feel for EQ <-> AFR, so switched to AFR to better see what was happening. I can certainly switch back. What, if I may ask, are the "other problems"?

critter
September 19th, 2007, 07:12 AM
B3605 is an interesting table. It has two humps at the lower MAP values in two distinct ECT ranges - a narrow one at 68-86 ECT and a wide one at 194-284 ECT. All the Camaro and Vette tunes I have, covering 1997 to 2004, are almost the same except for the Z06 and 04 Vette. The 19980100, 19980200, 19980400, 19990361, 09360361, 09381344 and 12212156 are identical. 12202088 is the same except in the 212-230 ECT range from 20-50 MAP, which makes a bump on top of the normal wide hump, or leaner in that range. 12593359, 09365637, 12593358, 12221588, and 12584929 are the same as the first seven except in the 68-86 ECT range from 40-100 MAP where they are leaner, and 12584929 is even leaner in the 104 ECT / 40-45 MAP range. This all seems a bit strange, but I assume they developed these tables with dyno or road testing. One caveat - since you can't compare different OSes directly, I cut & pasted to text files and in one case I caught, I didn't cut before pasting.

joecar
September 19th, 2007, 08:43 AM
I noticed the same humps in various OS's... they may have to do with emissions "quality", but I dont' really know.

When using EQ units, any multiplier tables just multiply in;
When using AFR units, multiplier tables don't just multiply in;

Someone on here has a spreadsheet to produce a table of EQ <-> AFR conversion that you print out and place in a visible place. :D

critter
September 19th, 2007, 02:14 PM
When using EQ units, any multiplier tables just multiply in;
When using AFR units, multiplier tables don't just multiply in;

Ah! The light bulb goes on!


Someone on here has a spreadsheet to produce a table of EQ <-> AFR conversion that you print out and place in a visible place. :D
Oy! I use 2 lines of Python .... :D But my new wife throws away loose papers :-(