I have an '808 SD system that I am playing with. I have a Holden Caldata sheet that a good samaritan gave me lately, but no 808 hack to even begin to understand how the stuff below works.

I've done some changes to cam timing and exhaust (headers, bigger pipe diameter, etc) and in the mid range (around 3500 to 4000) I've got BLM's up to the 140 limit in the code (ASBX)

The car will pull 6000 rpm easily, and I think it should be pulling more air there, but I don't seem to be getting any significant BLM increases.

I've tried long hills while attempting no acceleration, but I'm not sure that it's learning, and until I've got it back to a friend's dyno, I won't have a WB reading.

There is no PE on this BIN (is this the same on all SD's?). Only AE, and the parameters are as follows:
It says,
KMANRPM: AE Params - AE RPM Gain factor for MANFUEL calc = 128
KAEFUEL: AE Params - AE Delta Fuel AE factor = 32
KAETPS: AE Params - AE Delta TPS AE factor = 40
KAETPS: AE Params - AE Delta = 0.78%
KAEISCN: AE Params - AE Idle Air Control Contribution = 1.56 Msec
KAETATH: AE Params - AE Delta Throttle Threshold NTPSLD U = 0.78%
KAEDFTH: AE Params - AE Delta Fuel Threshold Manfuel Unit = 2.0

Is "Manfuel Unit" related to calculated extra fuel requirement from MAP increase, or is it something else (?) and the only AE comes from delta TPS? What is Delta Fuel factor? I dont' want to add AE, I want to allow it to log the right BLM's. Where/ when is this getting into AE mode?

On an earlier post, I recall Rbob said that BLMs get used in the PE calcs to correct for lean (ie >128 BLMs are used in fuel calcs) but rich corrections don't. Is this the case with these SD cals?

Given that you'll sometimes read people saying that you should go out and thrash your car to "get it used to hard driving", it seems to me that you actually want to do the reverse if you don't get BLM correction in AE mode, and yet you use the BLM correction if you change your VE through headers or otherwise.

I'd be glad of any clarification.

John

 

Which mask are you talking about?.
If you'd supply the mask and the locations for those terms maybe I could figure out the english eqivalant....

Or one by one make a serious change and see what happens. Often that winds up being my case, just change something and then drive the car and note the change.

 

Sorry,
ASBX is a $5d mask. It's the one off the DIY site, with 4, 6 and 8 cylinder forms.

John

 

That sounds like the Programming 808 one.
Doesn't seeing the variances from appl to appl help?.

You do have the 808 stuff, right?.

Holler if you don't or can't find it, I don't know if I still even have that data, but if you can't find it, I'll hunt around.

 

I have all the Programming 808 stuff from a previous search of the DIYEFI (pre GMECM) list thanks. I also have the "Caldata" file as I said above, and there's no way I can see to tell how AE mode affects the operation.

>>Doesn't seeing the variances from appl to appl help?

Not from what I can see. Without a hack (and probably even with one at my level of expertise ) it's not possible to see if AE mode switches off the learning function or not. And it's not possible to see if the BLM's that have been learned are used in AE mode, or if the ECM simply sticks to 128's plus the AE fuel.

Help needed please!

John

 

Now I'm puzzled,
why does any of this even matter?.

Run the entries up a few notches and see how the car responds.

Rather first error rich then lean.

 

Thanks for persevering with me- no one else seems to understand either!

My point is that although I can datalog the BLMs below 4000 pretty easily, I'm suspicious that at the higher RPM points (which I can't seem to maintain for long where I'm testing), I might be getting AE locking the BLM mode out, so the BLM's I log aren't much use for redoing the VE's. I don't have a WB, so all I've got to go off is the BLMs.

I've just burned another chip with <>10% in it at the bottom end and <>5% at the top. It feels great, but it could be the placebo effect again and I haven't had time to log it.

So how do I work out whether the AE mode uses the BLM's to calculate fuel requirement or not? And is there any point in switching it off to tune the car?

John

 

BL's at over 4K?.
I doubt that.
There is usually a RPM limit on BLs. Usually, being a key word.

Guess I tune, drive a bit different from you. By 4K in everything I can think of to date, I've been in PE.

AE is just so incredibly easy when you do have a WB to really see what's going on. Without it you'll be just using the SOP, but you can get there eventually, just takes alot longer.

By reducing your PE TPS enable, you'll have the addition fuel to work with, and might make life alot easier.

And from the sounds of things, you might be to where your running out of injector, but that's justa guess, based on what your looking for.

FWIW, also at the higher RPMs you can get to where your running out having a big Delta VE for AE. So you might start to have an S shape in your TPS AE entries.

Starting from 0 on the left
stock
128, 128, 128, 128, 128, 128, 128, 128.

First mod.
155, 175, 185, 180, 175, 128, 128, 128

Delta VE limited AE
155, 175, 185, 128, 128, 128, 155, 255

This are just off the top of my head, but are meant just to show ya what I'm talking about.

Now this is kinda advanced stuff here, so just don't plug these big numbers in and try them. Depending on what you have, you can wet fuel foul plugs with AE. Just ask me how I found out, LOL.

 

If there is a PE mode in this mask, it's beyond me to find out where it is (and a lot of other stuff as well )

There is therefore nothing like "PE TPS enable" that I can see in the $5d ECU.

What there is, is a 3D table: "Open loop A/F ratio vs RPM and MAP". It is 14.7 everywhere except for 95 kPa (generally 12.6 to 13.3) and 100 kPa (12.0 to 12.8). That looks like PE to me, but it's not so named.

I still haven't got a clue what locks it in open loop and whether it factors in the BL's to calculate a PW to achieve the target AFR.

John

 

No danger that I might "just... plug these big numbers in and try them"- I can't find a slot for them. No table like that that I can see in the $5d ECU.

John

 

Can you email me the Programming 808 stuff.
I just looked around but can't find my copy, I'm sure it's in there, if nothing else change it with a hex editor and then run it thru some other program to have it correct teh checksum, and try it that way.

 

Bruce,
I'd be glad to email you the 808 stuff, but your email isn't accessible through this board, nor your PM. Do you still have the nacelp address? If not, please PM me.

Thanks,

John

 

I've learned a little more about this since I first posted the question, and maybe this update will be useful to others running '808 code. Thanks to Grumpy for assistance so far. Please correct what I get wrong. The first issue is that I was sort of confusing AE with PE- short explanation that's correct, I now think, is "AE is accelerator pump to avoid flat spot" and PE is "dump more fuel in under WOT conditions to get some cylinder cooling, minimise risk of internal damage, and supply a little extra fuel to compensate for possibly incomplete mixing." (?)

If you look at an '808 ECU, you'll see its "PE" is supplied in the F60 Table: "Open Loop A/F ratio VS RPM and MAP" in my $5d ECU. See the attached image.

Note: this is open loop, not closed loop. As an aside, what is interesting is that you can get closed loop BLM's up to 6400 rpm on the AMXY bin I'm using (records that way in Winaldl). Bruce had said above, "BL's at over 4K?. I doubt that." It seems to me at least that my (reasonably ok) AFR's show that the BLM's I recorded and adjusted for are correct.

I've got a couple of interesting power curves from a dyno day that was run recently, that show a comparison between my Nissan Pulsar and a similarly modified one with a stock .BIN. Both made almost identical power, but mine had AFR's that followed the above F60 table settings pretty well. These are 4 cylinder, 1.8 Nissans with GM motors and SD Delco '808's standard. I know several Corvette drivers will be fearful of the 67kW at the front wheels, but if that's not good enough to beat them, I'll have to line my S/C 5L Holden V8 with $58 code in '730 up (well, one day anyway ). The only significant mods are free flow cold air intakes and headers/ free flow exhaust.

Standard .BIN chart with AFR curve:


My .BIN dyno chart with AFR curve:



What the two power runs show is that the standard BIN goes seriously lean at low MAP numbers (it's over 15:1 in several spots). My BIN has 20% in the bottom end on the VE's and about 5% top end increase. You'll also see two power runs on the second graph because it was pinging like crazy around 2500 to 3000 rpm (I'm pretty deaf and I couldn't hear it- the dyno operator had a mike on the engine and picked it up- it was worth about 10% power down low).

I got pretty close to a reasonable tune just using Winaldl off the standard NB O2S- even ok for WOT conditions because of F60 (shame about the timing though!).

The fact that the standard BIN goes seriously lean on the bottom end shows, I think, that the BLM's lock at 128 in closed loop and you only get the F60 table correction to AFR. This is a good reason not to use an '808 bin on a modified engine without burning a suitable prom- the self learning is no good to you when you most need it.

Conclusion:
'808 doesn't use BLM under WOT.
'808 PE is tuned by table F60.


John

 

You need to adjust your VE table to achieve the desired A/F as requested in the open loop table - running a tad lean there I see.
AE is to overcome instantanoious lean spots when the air is suddenly ingested , will not come into play on a eddy current chassis dyno ( may have a effect on a inertia dyno but you cant tune on one of those anyway)

 

Thanks for your comments, but I think you're reading the wrong chart. Mine is the bottom one, which shows AFR's between 12.3 and 13.1 against commanded "PE" AFR values of between 12.0 and 12.8, tuned with only the standard NB O2S (I now have a WB, which indicates the NB is pretty good). I think this is about as close as you'd expect to get under the circumstances, and my BLM's are also very close to 128's everywhere.

The chart that shows a "need to adjust your VE table... running a tad lean" as you say, is a standard Pulsar .BIN on the other car. Do you think there is any danger in running as lean as it is, where it is, or is 15.6:1 lean only a problem under high rpm and VE conditions (ie much more heat energy applied)?

I take your point about AE's (that's what I was saying in yesterday's post that I didn't understand properly when I started this thread 3 months ago). I should have been talking about PE effects all along, not AE. The point I'm making now is that the '808 doesn't have a PE function (it appears to me)- but table F60 is there for that purpose.

John

 

G'day John! Bumping one of your very old threads

I don't suppose you've had any further insights into AE tuning have you? I'm a little in the dark on this one.

I've been playing with ignition a fair bit, and I'm finding some transient throttle conditions which appear to be the cause of some detonation. As a result I've been looking for the '808 $5D mask equivalent of a Throttle Enrichment condition. AE sounds like a likely place to start, but I have no idea what to do with it at this stage.

Can you provide any insight?

Dave.

 

Dave,
As I recall it, you've got very high (11:1?) CR from using the F18 head with a heap skimmed off it. If that's correct, you've got almost insurmountable problems with knock, unless you get the octane number up (ie run PULP).

If it's not "transitional knock", you could try putting a heap more fuel into it (with F60), and/or pulling timing out in the high MAP areas. The fuelling may be best adjusted as "PE", not as AE (ie use table F60) but if it really is just transitional, then you could try varying table F37 (AE vs temp) at the higher temps (mine are the standard 1's over 80 deg C) - although I haven't tried this.

John

 

Thanks John.

You've got the engine right, and I'm already running on BP 98 RON fuel. I've already got the fuel and ignition down to a fine art and under steady throttle conditions it's absolutely perfect.

The only time detonation seems to occur is either under a quick throttle increase (most obvious while downshifting) or when the revs have dropped dramatically when the clutch is released too fast. It fits that these two conditions correspond to TPS AE and MAP AE. Now to play

This is at least the fourth time you've pointed me in the right direction. Many thanks!

Dave.

 

Might try working with the Burst Knock Retard, settings.

 

No factory knock sensor on the F18E. I know another fella who's been working on one, but he was never able to get it working satisfactorily.

Thanks for the suggestion.