Ignition maps - show us yours

[Jonny Rochester]

The only dyno tuned part of my map is the 100% line, and I only did 3 power runs to decide best advance at full throttle. 38 degrees is a fair bit I guess. My base timing at the CAS could be off by 2 degrees so go back to 36 if you copy this.

The advance at idle does not matter very much. More advance gives torque to drive A/C and headlights.

All the number right in the middle or the map, around 3000rpm, is where the real performance and response is. I have a fair bit of advance here. A dyno power run does not touch this part, but it is what makes a car fast on the road.

The 0% line, where it goes up to 45 degrees, does not matter so much.

Putting the car in 5th gear and driving off from a stop may see that 500rpm vs 80% area. Too much advance here will stop the motor real quick. You don't get there often, but it's nice to fill the map out.

[gixer]

The advance at idle does not matter very much. More advance gives torque to drive A/C and headlights.

All the number right in the middle or the map, around 3000rpm, is where the real performance and response is. I have a fair bit of advance here. A dyno power run does not touch this part, but it is what makes a car fast on the road.

I often use timing around the idle speed to control the idle speed, for example if you want it to idle at say 800rpm, and ignition timing is say 10deg, below 800rpm you start ramping the timing UP, and above 800 rpm bring it down, it keeps the idle REALLY stable, use idle speed control valve to control any additional loads. If done right, you can have your electrical loads come in while the rpm still stays low and the engine just purrs away.

A dyno power run doesn't touch that part, correct, but steady state load test does, this is where you tune MTBT and optimise it, hold it at say 3000rpm and alter your throttle angle whislt optimising torque, I did this a few weeks ago with a group of people on a 2.6ltr turbo gemi and they were astounded at the monumental leaps in torque as timing was optimised at load points.

[thechuckster]

If you don't have a lot of tuning experience, I can see where your coming from. If a map is filled out with lots of different numbers down to a few decimal places, it looks "tuned". However this is often guess work. Even if a car is tuned on the dyno, there are a lot of things to look at, and fine tuning ignition is only 1 thing to do after more important things. And a basic ignition map works very well.

That's all it is - a basic map that replicates a old dizzi with mechanical-only advance that tops out at 3k rpm. Would be ideal for an bog stock 18RC used in drag racing.

It fails to take advantage of the power output and high-end flexibility of what is a high-revving engines. There's no timing alteration to assist acceleration. It would make it prone to pinging with sudden shifts to WoT with high MAP values. Trailing throttle to assist engine braking. etc.

The map might get a car running so you can then go an tune it - but actually paying for that tune? May as well put money in a box and set fire to it.

btw: my tuning experience is several years of installing and using/using and MSEFI ECU. I got the 18RTE running by simulating an 18RG dizzi and then went on from there using seat-of-pants and datalog analysis (from highway, constant load, drag racing, daily driving, cold start, etc. events) to tune fuel & spark (as well as accel and AFR tuning/targeting).

[oldeskewltoy]

the next map I'll be using....... I've got cast pistons in my engine, so I can't get too advanced(lean) with it while under power

[Jonny Rochester]

Can you please explain the logic of that map? I can't follow.

[oldeskewltoy]

Can you please explain the logic of that map? I can't follow.

I assume you mean my last map posting, can you be more specific with your question? I'll toss up a few answers to cover assumptions.....

1) The darker #s are often the place where WOT is initiated.

2) The italic #s is the area of highway cruise

3) less detail is required on the ignition as RPMs climb, more detail is required as the ignition is transitioning (lower RPMs)

[Jonny Rochester]

It would seam to me you are missing out on some power at WOT up around 6000rpm. I think it should be advance to about 36 degrees here. Just a surgestion.

[oldeskewltoy]

It would seam to me you are missing out on some power at WOT up around 6000rpm. I think it should be advance to about 36 degrees here. Just a surgestion.

You may be right........

the one thing that worries me some about that much advance is I'm still running cast Toyota pistons... the ring lands are noted to be fragile... I'm trying to produce power without being excessive on the pistons...

I can also add more ignition... that is the beuaty of mangement - its ever adjustable

[1JZ-Rolla]

I often use timing around the idle speed to control the idle speed, for example if you want it to idle at say 800rpm, and ignition timing is say 10deg, below 800rpm you start ramping the timing UP, and above 800 rpm bring it down, it keeps the idle REALLY stable, use idle speed control valve to control any additional loads. If done right, you can have your electrical loads come in while the rpm still stays low and the engine just purrs away.

Agreed, this is a key point that many tuners/DIY'ers miss. Building inherant stability into the idle speed through ignition tuning is very useful, particularly on cars without idle control, or shitty limited idle control logic like the E6* range of Haltechs etc.

You guys are pretty keen making judgement calls & providing advice (add timing etc) on other's ignition maps without knowledge of the particular engine & its supporting components. Sure, there are standard approaches based on theory/experience that may apply that you can argue, but there's no substitute for actual dyno time in the real world to analyse what is actually happening, particularly when there's the chance of causing real damage

[oldeskewltoy]

You guys are pretty keen making judgement calls & providing advice (add timing etc) on other's ignition maps without knowledge of the particular engine & its supporting components. Sure, there are standard approaches based on theory/experience that may apply that you can argue, but there's no substitute for actual dyno time in the real world to analyse what is actually happening, particularly when there's the chance of causing real damage

Well.... dyno time all depends on the shops capability to use the tool(dyno). I've had 2 shops "tune" my car so far and the results were barely adequate. Even with a dyno... certain things you just can't simulate... From what I'm beginning to learn, WOT timing isn't the challenge, its low speed transition timing, under varing load points*, that is the REAL challenge to the tune

* - temps, AFR targets, traffic conditions - varying low speed inputs (just a few of the variables)

[1JZ-Rolla]

For sure, any dyno tuning (particularly if only done in a steady state & WOT power runs) should be followed by a road testing session to check the results. A good tuner is unlikely to give your car back hot off the rollers without this.

[allencr]

Can anyone show those graphs in that 3D style with all the colors?
They look very pretty, like a smooth or fucked up version of a mechanical advance that has a fucked up(operating as designed) vacuum advance with it.
*****
*****
*****learn, WOT timing isn't the challenge, its low speed transition timing, under varing load points*, that is the REAL challenge to the tune

It'd be excellent for a stationary pump & generator engine and a boat engine, but a car needs more.

[twentyEight]

I'm no good at reading these things, so does this look any good as a Fuel Map? (I haven't started it yet, but just want to check a few things before I do.)

Gen III 3S-GTE with GT3076R

[MWP]

Its impossible to tell from that...
It looks like a fuel map should, but who knows how well itll run your particular engine & setup.
Could be far too rich or lean.

Only one real way to find out, dyno time or wideband on the street.

[oldeskewltoy]

Its impossible to tell from that...
It looks like a fuel map should, but who knows how well itll run your particular engine & setup.
Could be far too rich or lean.

Only one real way to find out, dyno time or wideband on the street.

well put

here is the fuel map for my 4AGE using 320cc low ohm injectors