First RT Tuning Experience - OSE 12P BCLF based Camaro

[redcamaro]

It's too easy,.. with real-time tuning, just need some experience.

Hopefully, this topic (goes "viral", and will give insight to those who are starting out - like me

The bin that I started with was OSE 12P BCLF, I had to make a couple of changes to get the motor running i.e. change the spark reference angle from 60 to 10 (9.84), and set the road speed multiplier to match the vehicle speedo using a mix of calculations and GPS.

The first tune session went something like this:
1. turned on diagnostic mode
2. moved distrubutor to maximum MAP vacuum without stalling, decided to back [from 9.84] to factory 6 degrees, and set that with a timing light.
3. set the diagnostic and bypass mode timing to match, i.e. 6 degrees.
4. IAC got it idling at 750 rpm and IAC at about 20 steps, then set initial IAC position to match 20 steps.
5. read Tuning Basics again, then matched the transitions between the 20-100 kpa Spark Advance, and the EST Idle Spark Advance.

The timing isn't finished yet, there's a big difference between the default BCLF bin and what runs best on my car. I started with data tracking at idle and matched the Spark Reference Angle scalar to what is physically set at the crankshaft - then started expanding from there. The stock BCLF timing is far too advanced for my setup. A little bit of driving was involved.

It would be great to get some comments on how and where to proceed.

The bin file that I'm modifying, and corresponding log are attached.

[Holden202T]

just a question, why did you use 6 degrees cranking advance rather than 10 ?

[redcamaro]

I used 6 because that's the stock standard setting - I don't know why else - no reason. I was thinking about contacting Comp Cams again and asking them where I should set it for the cam - http://www.compcams.com/Company/CC/cam- ... d=195&sb=2.

Of course the stock setting is based around having the EGR working, etc...

Quick answer is - I don't know,.. why do you ask?

[Holden202T]

because everyone i know uses the standard 10 degrees that holden had them come out with, and only changes the setting if needed for custom crank trigger etc.

i know my 202 struggles to run on 10 degrees advance let alone less but really its just for cranking the motor so if its starts ok its not a big deal.

[redcamaro]

There's more MAP vacuum at 6 degrees. At the time I thought may as well start at the stock setting. I'll be happy to change it later if it runs better at another angle.

Thanks for your interest Holden202.

Did anyone get a chance to look at the attached files?

[Holden202T]

yeah thats why i asked, you say you have the dizzy set at 6 degrees, and the bypass timing is set at 6 degrees, so in diag mode the timing will be as per the balancer, but the problem is your reference angle out of diag mode is 12.30 degrees, this means when the computer is commanding 6 degrees it will actually be 6 degrees out from that point!

if you want to leave it at 6 degrees base timing that fine just make sure the est - spark reference angle matches!

also i cannot comprehend why you have changed some of the settings that you have ..... idle spark timing doesn't make sense to me.

does your engine idle ok at the blcf stock desired idle settings ?

[redcamaro]

A little oversight there, with the Reference Angle incorrectly set at 12.3 degrees - it's now 5.98. Thanks for pointing that out Holden202.

I thought that 6 degrees would give me more of an adjustment range, but after going for another drive and looking at the timing advance it's probably not necessary to go back to 6 degrees. I'm considering putting it up when I have a better idea of where it runs best.

This tuning session I adjusted the entire MAP A: EST - 20-100 kpa Main Spark Advance vs MAP vs RPM table using +/- offsets until the engine started knocking a bit under heavy load. That's also when the SES light came on and I got codes 24 (Speed Sensor) and code 35 out of it. I don't have a code 35 in my Service Manual - what is that?

Would it be IAC - looks like these are related to the Road Speed issue. What Trouble Codes list is relevant to OSE $12P?

The EST Idle Spark Advance as a function of MAP table doesn't match with data tracing, but I guess I'll go back and match it once the main table is done.

I also found that two of the spark plug leads were burnt from the headers, so I rerouted them all.

Here is the bin and corresponding log:

redcamaro_tune_002.bin

redcamaro_tune_002.xdl

It's still not right because I don't know what I'm doing. Your continued feedback is appreciated.

Road Speed

The road speed display isn't working on the dashboard. Would that be due to the ADX file, or an ECU wiring issue?

This is the ADX file:

OSE_$12PV111_1BAR - Petrol.adx

also i cannot comprehend why you have changed some of the settings that you have ..... idle spark timing doesn't make sense to me.

does your engine idle ok at the blcf stock desired idle settings ?

I'm not sure what your asking me about Idle Spark Timing? I was trying to match them up with the MAP A: EST 20-100kpa table with data tracing, if that's what you mean.

In the redcamaro_tune_002 bin I put both these tables back to BCLF settings and then used +/- offset to advance/retard the timing. First on both tables but then, decided to leave the Idle one for later.

The engine idles ok as low as around (or even less than) 500 if the fuel and timing are right.

[charlay86]

The trouble codes and their thresholds are all in the 12p xdf; dtc35 is idle speed error.
DTC 24 won't be set until you exceed a particular engine speed & load without detecting VSS pulses.
The VSS is also used to determine when to go into idle mode...

[redcamaro]

Thanks charlay86, I'm checking it out right now. I suspect it's a wiring issue. Then I'll post another redcamaro_tune_002 log.

I must have been running off the Idle Spark table, doh! no wonder things didn't seem to change after I decided to leave that table for later.

[VL400]

A little oversight there, with the Reference Angle incorrectly set at 12.3 degrees - it's now 5.98. Thanks for pointing that out Holden202.

I thought that 6 degrees would give me more of an adjustment range, but after going for another drive and looking at the timing advance it's probably not necessary to go back to 6 degrees. I'm considering putting it up when I have a better idea of where it runs best.

I dont think your understanding the relationship between ref angle and spark advance yet. The ref angle just needs to be set to match whatever your engine is mechanically set to with the dizzy. It could be anything from 0-90deg depending on the trigger setup and ignition module. In your case being an 8 tooth reluctor signal from the dizzy its easy, needs to be somewhere that allows for the easiest starting when hot and cold as it will provide some cranking advance - thats it! Lets got with 10 degrees, so with the engine at 10* BTDC one of the little teeth will line up exactly with the center of the pickup in the dizzy - if not twist the dizzy till it does. When the engine is turning you will get a pulse at 10degrees BTDC. So, you know when the pulse happens but the ECU has absolutly no idea where this is happening so you need to tell it - set the ref angle to 10 degrees. Providing you were spot on setting the dizzy to the middle of the tooth the ECU will know when the pulse comes in the engine is at exactly 10* BTDC and can calculate when it should fire the plugs for a given advance.

Unless you have a degree wheel and can set a system delay in the ECU there will be a little bit of error setting that up. This is where the diagnostic mode comes in to play. You set the diagnostic advance to whatever the biggest timing mark is on the balancer (lets say 6 deg as that was your factory setup and most likely to be marked on it). Put it in diagnostic mode and the ECU will command 6 deg of advance (it calculates this, its not hardware triggered), and you twist the dizzy untill its exactly 6 deg (it should have been very close).

Now dont touch the dizzy again! When the ECU commands 25deg it will deliver exactly 25deg and during cranking you will have pretty close to 10deg. No matter what the ref angle you can have whatever range of advance (within the limits set in the calibration) - you just need to set the advance in software.

That's also when the SES light came on and I got codes 24 (Speed Sensor) and code 35 out of it. I don't have a code 35 in my Service Manual - what is that?

Would it be IAC - looks like these are related to the Road Speed issue. What Trouble Codes list is relevant to OSE $12P?

With code 24 id say its a wiring or sensor issue, the ADX and 12P speed will work. And it used to work didnt it?

Code 35, will need to check that your target idle speed and actual are ok. There are times your IAC counts are at 0. Fix the VSS and reset the ECU, then take another log to see when it happens and can fix it