1FZ FE Ignition curve

[hazard]

Hi
Wondering if anyone knows the stock ignition curve, or a good designed curve, degrees at different rpms for this engine. I know it is adjusted by ecm but there should be basic curve data. With my scan tool I have seen it anywhere between 4 and 38 degrees while driving.
I need it as I am running engine analyzer software to help design my build
1FZ engine building and blueprinting
and it would be more accurate as without it program sets timing and fuel for best power but its not real world driveable and has high knock values. So far I have put in all the stock info, including cam specs, and it is accurate, against stock spec by about 2hp and 3 TQ

Thanks

 

[hazard]

Spark Advnc, deg 16.2 18.2 19.8 21.1 22.0 22.7 23.4 24.6 26.0

This is what the program has set in 500 rpm steps starting at 1000 rpm

 

[gbeltran]

I wonder if it even has a curve. Since it's computer controlled I would think it just runs the advance up to a maximum set value, and then just backs it off it it detects a knock. It probably takes all the sensor values into account and then adjusts. Not like an old distributorvwhere you can change weights and springs to come up with something you like.

 

[hazard]

I wonder if it even has a curve. Since it's computer controlled I would think it just runs the advance up to a maximum set value, and then just backs it off it it detects a knock. It probably takes all the sensor values into account and then adjusts. Not like an old distributorvwhere you can change weights and springs to come up with something you like.

I think you are probably right.
Any idea on a reasonable curve for a stock setup that I can input to program?

 

[gbeltran]

I do not, however I'd keep it kind of conservative, it's a heavy car with a tractor type engine made to lug all that weight around. Probably doesn't need a whole lot anyway, the head has a pretty efficient chamber design.

 

[Kaninja]

I do not, however I'd keep it kind of conservative, it's a heavy car with a tractor type engine........

Tractor engines are awesome.

 

[landtank]

I've logged the advance but havn't plotted it. It aprears to me to be linear up to 40* adv at red line.

 

[BILT4ME]

@scottryana Do you have any idea? As much turbo stuff and programming you've studied, I would guess you know where to find the appropriate info.

 

[scottryana]

Landtank has the most appropriate data. Since I am running a standalone, I really don't know the stock ECU timing, I set my own timing. But Rick (Landtank) has data logged a stock truck going a pull and if he says it is a linear progression, I imagine he is likely one of the only people who knows.

But this is a lot trickier than one would expect because since it is electronic, I would imagine there is a host of differences depending on; how hot the coolant is, how much throttle position there is, what the IAT is, etc.

@scottryana Do you have any idea? As much turbo stuff and programming you've studied, I would guess you know where to find the appropriate info.

 

[Rivman1243]

Couldn't you put the ecm into service mode and check timing with a dial back timing light? Wouldn't that give you the base curve?

 

[landtank]

I've data logged several pulls but all were done the same way. The truck was a 1995 with a 1997 ECU installed. The truck was set for 2nd start and the transmission was in 2nd gear. So the truck would start off on 2nd and hold 2nd for the entire pull. I recorded from a dead stop to @5200rpms.

Personally I don't see our ECUs as being anything much more than basic fuel management with some protection protocols. These were the first OBDII complaint boxes and I have to believe the engineers had their hands full with just meeting that criteria.

 

[scottryana]

Well I know for sure it changes fueling and timing based on coolant temp. The rest I am just making an educated guess. But I would think timing would be different at 3000rpms at WOT then at 3000rpms at 25% throttle, but that is just a guess.

I've data logged several pulls but all were done the same way. The truck was a 1995 with a 1997 ECU installed. The truck was set for 2nd start and the transmission was in 2nd gear. So the truck would start off on 2nd and hold 2nd for the entire pull. I recorded from a dead stop to @5200rpms.

Personally I don't see our ECUs as being anything much more than basic fuel management with some protection protocols. These were the first OBDII complaint boxes and I have to believe the engineers had their hands full with just meeting that criteria.

 

[landtank]

It looks to me that load plays into timing as you stated.

I was thinking more on the line of adaptive timing, that sort of more advanced stuff.

 

[hazard]

Point of thread is that I need a realistic ignition curve to input into my engine analyzer software.
The program adjusts for best power now but it pushes high on knock index so I would like to manually put one in.
I know driving my 80 and watching my Scan Gage I see reading from 4-38 degrees. Obviously all the comments above are valid and the ecu changes it constantly due to many parameters and inputs.
But I believe even when you have a standalone ecu you will have to design some sort of a curve, althouygh the better ones are "lself learning" so they probably change on the fly also.

 

[White Stripe]

I am not aware of any self learning timing curve software. EFI timing curves are fairly complex. I would probably see if you could find a timing curve to a 258 I6 jeep motor and use that as a starting point. Its a similar style motor and very popular and you are more likely to find that timing curve. To develop a really good timing curve from scratch you need a dyno and a lot of time and a way to monitor knock. I have modified timing tables for my 2f with fuel injection without a dyno and have gotten it decent. I suppose with the right equipment you could data log the timing. But you would need to record timing, rpm, map, maf voltage, coolant temp, and loop status.

 

[Rivman1243]

I am not aware of any self learning timing curve software. EFI timing curves are fairly complex. I would probably see if you could find a timing curve to a 258 I6 jeep motor and use that as a starting point. Its a similar style motor and very popular and you are more likely to find that timing curve. To develop a really good timing curve from scratch you need a dyno and a lot of time and a way to monitor knock. I have modified timing tables for my 2f with fuel injection without a dyno and have gotten it decent. I suppose with the right equipment you could data log the timing. But you would need to record timing, rpm, map, maf voltage, coolant temp, and loop status.

I have a SnapOn verus Pro scanner that I could log some data with. I can log all of those parameters and more.

 

[White Stripe]

I have a SnapOn verus Pro scanner that I could log some data with. I can log all of those parameters and more.

That would probably be what you need then. I would be curious how easy or difficult it would be to use the verus for that. I would be interested to see what toyota's timing maps look like. Especially during cruise.

 

[Rivman1243]

I would be willing to log some data. @landtank has stated he already has some timing recorded