Timing table question

[timwds]

Please correct me if I'm wrong...
The idea of having two timing tables is to compensate for different octane fuels.
My understanding is the ecu will clip the max timing to the corrected MBT table.
If I was to fill the borderline spark table with 50s, could I then use the MBT like a standalone/traditional timing map and only run on high octane fuel?
If so, what are the drawbacks?

Thanks

[JETURBO]

Its not "soley" for octane levels, its for a multitude of events much like the holden twin tables, its become common practice to make the BLK and MBT the same ( well for some tuners )

Ive NEVER done this ever

The amount of "smarts" attached to the MBT table is for reasons....

Remember you should have a vehicle in the BLK "territory" when calibrating that table

Its easy to be in "limbo" between the two "sometimes"

[Yortt]

Timwds, it appears you are coming from a GM tuning background as did I. I suspect the Ford MBT table serves a similar function to Holden maximum torque table with the Holden table it is recommended that not be changed. I think that is advisable with the Ford MBT table even though it was usual practice in the early days to make this the same as the Border line knock table.

It appears that the timing control in the Australian fords has a lot more going on than the Holden LS1 timing control in relation to automatically adjusting timing due to knock sensor activity primarily to accomodate a change in fuel octane. How this is done is unclear and I have seen nothing posted on it maybe others can shed some light!

Without VCM suite having knock detection in the scanner your biggest problem is determining accurately where the knock threshold is.

[timwds]

Thanks guys,

My background is more aftermarkets and dirty skylines which I find are more comparable to the Holden gear than Ford.
I'm possibly the kind of backyard tuner that Jet hates That said, I'm on a never ending quest to gather information and do things the "right" way.

I understand why Ford do things how they do. No car is the same, gets used the same or wears the same and the ECU has a ton of data to help make the right decision based on the information it has. It definitely complicates thing though.

[DarrylC]

Its not "soley" for octane levels, its for a multitude of events much like the holden twin tables, its become common practice to make the BLK and MBT the same ( well for some tuners )

Ive NEVER done this ever

The amount of "smarts" attached to the MBT table is for reasons....

Remember you should have a vehicle in the BLK "territory" when calibrating that table

Its easy to be in "limbo" between the two "sometimes"

Jet, anyone, I am trying to learn how these tables work so to clarify.

If you extend the Load by increasing boost or changing the SD tables then you will need to alter both tables. I have seen comments that the MBT table should be left at Fords values (Eric and Donald La Sota have both made this comment) but I believe Ford did there figures for 95 octane so we would have to use the octane adders to calculate the actual spark for 98 just for the Ford figures.

Many tuners copy the table over and I have seen Eric, VCM and other recommend this. I have also seen tunes where the tuner has left the MBT table alone and changed axis on the Borderline table making an absolute mess of the MBT table.

My understanding is that the car should make maximum power (torque) at the MBT (Maximum Brake Torque) and it should fall off as we head towards Borderline Knock (spark hook curve) but this would move if we change octane. So I would guess the car is transitioning between MBT and BLK under normal conditions. Even more confusing is the tables seem swapped over with the MBT table being much higher that the BLK table but I guess that changes with the Lambda, ... adders.

If this was correct we would run the car on the dyno adjusting timing until we got maximum power and that would be MBT. Then we would increase timing until we found the highest pointy before knock and that would be BLK. I guess it would be quicker to find the BLK with a knock sensor and then set the MBT accordingly.

I doubt I will be able to do this without an external knock sensor as I have not found the SCT logging to be brilliant but that is probaby my understanding.

[45T-XR]

I found "back yard" to be pretty much bang on for me... I don't mind though- It just cuts people deeper when your car is faster.
I do agree that a bit more info on the two spark tables would be good and what is considering "best practice"
I've heard multiple people do very different things ranging from copy pasting the BLK to MBT and adding 2 degrees to ensure it is the higher of the two at every load point (the theory was to ensure the PCM would only ever be referencing the BLK table) I believe there is a PID in SCT that allows you to log the spark source but I've never used it.
Personally I leave the MBT table pretty well alone, and I turn my knock sensors off, and they have been for over a 2 years. I found that I don't have the gear to correctly calibrate them to accommodate my built engine, the forgies are marginally louder through the knock box. This wouldn't be an ideal situation for a customer car and I wouldn't recommend it. But hopefully the smart guys chime in soon!

[JETURBO]

First up i really couldnt give two chits about the term "backyarder" I probably know more "backyarders" that have done better work that so called professionals.....

Daz your all over it and your thought process is on the level

Tim the thing that gets "old quickly" is people trying to get measured results with no measuring tools

Would you build an engine and expect ultimate hp without a torque wrench ? No ? So why are people trying to calibrate a timing map with either nothing or a false reading SCT device ?

Iam far from "professional" and I'll happily be in the "backyarder" group , fuck i dont know it all and id be a pretentious prick if i said i did ffs, ive asked more than my fair share of questions along the way and can sympathise with the dud answers when i asked stupid questions or zero data to at least back up my question

First thing, there are many many ways to tune a turbo falcon, its how u want to go about it, how much time you want to spend and if your ok with just a top end figure or after a complete calibration...

The MBT table is there for a reason, log spark advance at part throttle dyno runs and see it work and where it doesn't and where it hangs between the two maps

Make that your first part

Then go spend some money on tools and log till u cant log no more, it will make sense VERY quickly ( as long as u know what should be happening)

Then come the tips n tricks to making it come together,

Most of you should know that knock should be evident before it happens when logging the torque figure on the dyno, it throws up all kinds of warnings when dialing in timing, but yes you do need to see knock at least once imho ( this can get a bit long winded so ill stop here )

As a side note i fully understand why some people leave knock sensors off but i find it the worst practice for a car driven by anyone else who would not know what to expect or to look/hear/feel out for ( no dig at you 45 )

If someone wants help setting up a KMON knock sensor I'll happily help as the fine calibration and locations play a key part to getting readings

[turbotrana]

You are just going to rack your brain trying to understand how it all works. There comes a point in time with modifications where I would just zero out all spark adders and probably just keep a couple of spark subtractors going and make both MBT and BLK equal.
With aftermarket tuning I never had problems just running one timing map cause I alway knew what fuel I was using and what was going on.
For the guys that pay everyone else to work on their car and don't know what is going on, there is not much choice but to keep the protections there as much as possible.

[timwds]

If someone wants help setting up a KMON knock sensor I'll happily help as the fine calibration and locations play a key part to getting readings

A Kmon 2 is on my wish list. Is there much involved with setting it up? The online manual is more of a brochure :/
Is the extra sensor worth it?

[JETURBO]

Yes getting it to read for our application can be a bit tedious but ill help out of u get one

One sensor is fine for our cars

[45T-XR]

No stress at all Jet!!, I'm not offended at all nor did I see it that way. Like I said I wouldn't leave a customer car like that at all. This is purely my own car. I sort of follow Tranas idea there on my car, I zero everything out that adds timing, then tweak the stuff that pulls timing based on CHT, MCT lamda. Jet, how does the Kmon compare to say logging the stock knock sensors with SCT. Similar results?
The only reason I ask is my Knock Box is great for dyno tuning etc I can't log it into the log file in the scanner.

[JETURBO]

The K-mon is as good as a VIPEC i have at my grasp, i like the VIPEC a touch better as it comes with quality headphones where as the kmon unit is good but comes with cheap arse headphones so they need the bin straight up

They are both quite far away from the junk SCT throws up would not even say compareable

To be fair for low end players you can make something out of the SCT and for cars that did not require everything thrown at it we can get away with using the SCT as a quick ref because we know how it acts against expensive knock devices

Things like the 5.0 s/c GT/GS does not have any SCT KR support so your "forced" to use aftermarket devices, its a brilliant tool that imho you cant go without !

[FPV_GTp]

LOL I'm to scared to as a stupid question - 2 weeks

cheers

[timwds]

ill help out of u get one

I hope so 'cause I just ordered one

[Yortt]

Yep two weeks and all this aftermarket stuff will become obsolete.

[pmkolarik]

I was always under the impression that the BLK table was only referenced whenever the engine was running at lambda 1 (only interpreting the way that VCM describes it), but now I fear I could be wrong?

[timwds]

That means it was calibrated at lambda 1 , not referenced at lambda 1.

[pmkolarik]

BLK.jpg

I guess I interpreted it wrong then. I assumed, by what it says, the map was referenced at lambda 1 but calibrated at operating ECT/IAT.

[lukearmstrong1990]

final 344rwhp.hptstock.hpt

apologies for dragging up an ancient thread but I wonder if someone could explain this...

this FG XR8 made 320rwhp..... the only change between that and the 344rwhp done immediately after the flash was to copy the BLK table from load of .80 to 1.00 and 700-6000rpm into the MBT table and add 5 degrees to the new values.

I have no idea how this works but I saw someone do it once so I tried it. over 20rwhp gain from the one change. and it logged identical timing in the scanner (I don't have the logs saved)

any explanations?

[IH8TOADS]

What exact DMR were you logging in the scanner? Could be a scanner issue. If you add 5 degrees via bkt/mbt, you should see a timing increase and subsequent power increase (subject to fuel quality and knock of course).