Top 10 Signs That You're New To Tuning

[Fred]

Fred's guide to spotting a standalone tuning n00b! If you feel singled out by this, you might be, but probably not :-)

1. You feel like you need a base map
2. You want to use OEM tune data as that base
3. You think closed loop is required
4. You're excited by knock sensors, a lot
5. You've got to have sequential and/or COP
6. You think auto-tune really exists
7. You don't bother calibrating your hardware
8. You need two tunes: power & economy
9. You think adjusting VE (or MAF) is tuning the engine
10. You didn't enjoy reading this list :-p

This post is meant to be amusing to the experienced and helpful to the n00bs, even those who think they're not.

Fred.

[Fred]

An explanation of each item from the list:

You feel like you need a base map

On a new unknown engine, with good hardware, and correct calibration and setup, you can have a drivable, safe, powerful setup, from a blank sheet of paper, in much less than an hour. An experienced tuner of stand-alones is very unlikely to care about base maps as they know how easy it is to reach that state. The time sink is in getting it good, and a pretty looking map may hinder this process through distraction, rather than help.

You want to use OEM tune data as that base

How long will it take you to gather and translate that data, IF it's available and IF it's translatable (compatible algorithm wise, most is not)? A lot more than to start from scratch! Even then, if your engine is no longer stock, it's mostly meaningless anyway! Clearly this doesn't include sensor calibration data such as thermistor and MAF curves.

You think closed loop is required

Anyone that's ever used a good, or even mediocre open-loop tune can and likely will tell you otherwise. If open loop isn't working for you, your tune is shit, or your setup wrong. Furthermore, Any good closed loop system is founded upon an excellent open loop setup. Without that it causes FAR more problems than it solves. Caveat: If you're running fuel that varies a lot in composition you'll likely need to tweak an open loop tune for that.

You're excited by knock sensors, a lot

Knock sensors are there to monitor for bad fuel and other abnormal and potentially harmful conditions. IE, if you're careful with your fueling and coolant level and so on, it's not much use, really. Additionally, the strategy of advance till knock, then retard will be a costly one if your engine is not NA. IE near useless at high power levels. That's not to say that they don't have their place. They do, they're just of limited use for a typical standalone owner who pays close attention to their car and has a quiet valve-train.

You've got to have sequential and/or COP

Injection:

• Batch/Bank: Can be less smooth than you'd like, makes power, is drivable, gets economy, etc just fine.
• Semi-sequential: Smooth, slight economy/emissions/responsiveness benefits at low RPM
• Sequential: Smoothest, can tune per cyl IF you have data, slight economy/emissions/responsiveness benefits at low RPM

Caveat: outboard injectors with ITBs need sequential, BIG injectors benefit from sequential.

Ignition:

• Dizzy: 4cyl to 8k
• Wasted: to 10k
• COP: to 20k

Basically, you only need it if you need it, otherwise you just want it. Most engines will run just fine (smooth, powerful, economical) with wasted spark and semi sequential.

You think auto-tune really exists

You're totally wrong. Things marketed as such by others are typically auto-calibration, which is very very different. Tuning your engine is the process of finding the optimal lambda and timing combination for each and every load and RPM site. To complicate this, there is a range of combinations (less timing, more fuel, and vice versa) which will work well for each site on a given engine. Assuming stable weather conditions and a warmed up engine in good condition, the process 4 dimensional (load/rpm/afr/timing). If you have a coarse map at 8x8 and test 8 variants of each, you're looking at 8*8*8*8 = 4096 combinations and a LOT of time spent.

You don't bother calibrating your hardware

A foolish and costly mistake indeed. Failure to properly setup your engine's physical parameters before calibration and tuning effort is expended is just wasteful. When you do get around to setting up your config properly, your tune will be wrong. Additionally, in some cases the wrong config will make it difficult, or even impossible to actually reach a good state of tune.

You need two tunes: power & economy

This may seem obvious, but at WOT you want best torque. Torque requires fuel. WOT uses fuel. Best economy = drive more gently. If you drive gently, you'll be in parts of the map where leaner more advanced operation is possible and will get good economy. Whilst it is true that you may want different tunes in some areas, it's mostly not true and just an optimisation over a state of tuning finesse that most of you will never reach.

You think adjusting VE (or MAF) is tuning the engine

This is the process of calibration, not tuning. This lets the EMS know (approximately) how much air is entering the engine, not how much fuel to put with it. This step is a necessary prerequisite of tuning, but is not actually tuning at all. It's equivalent to setting up the base timing such that when the ECU thinks it's at 10* BTDC it really is.

You didn't enjoy reading this list :-p

I'm not a shrink, look elsewhere for this information :-p

Fred.

[tpsretard]

sequential is mandatory in my turbo race engines as Antilag on batch or semi seqwntial can lead to partially fueled cylinders.

wasted or cop is also mandatory as a dissy will not give the broad range of ignition timing needed for the antilag to work. -64deg at about 40 deg..

but again race engines or crazy asses like me with a race engine in his every day car

The knock sensor is good for tuning, you can also use it at high rpm is you know what you ar doing and what you are looking at. but useless for active correction
other than that, you are spot on.

[Fred]

Right, those are good examples of NEED not just want. And if you do legitimately need them, OK :-)

And agreed re knock sensor, active correction is what I meant, it has its place for tuning.

[molak]

sequential is mandatory in my turbo race engines as Antilag on batch or semi seqwntial can lead to partially fueled cylinders.

wasted or cop is also mandatory as a dissy will not give the broad range of ignition timing needed for the antilag to work. -64deg at about 40 deg..

but again race engines or crazy asses like me with a race engine in his every day car

The knock sensor is good for tuning, you can also use it at high rpm is you know what you ar doing and what you are looking at. but useless for active correction
other than that, you are spot on.

Do you use an antilag that cuts fuel???

[DonTZ125]

Having two maps for dry vs wet can come in handy when the engine is powerful enough to overwhelm the tires faster than the driver can modulate his wrist / foot, but that's more of a race thing than street.

Making too much power on the street? Take the lead out of yer frickin' socks ...

[Hentai]

not about making to much power on the street, its about not needing to waste fuel. Tons of times you will go into boost easily and don't need to be rich, stoichmetric will suffice.

[DonTZ125]

What? Not a turbo guy, but I was very much under the impression that boosting at leaner than 12:1 did bad things to your engine. Willing to be corrected ...

[Fred]

He's talking 1 2 or 3 psi or so. Still, running stoich at WOT NA is not something that will work on every engine.

[Hentai]

Actually its setup that TPS controls the fueling, eg above 70% throttle under 3800 revs = stoich above is around 12 and goes down to 11.5 later on
so its more setup like a torque based model, want more go, press the pedal down more.
Only issue is the current system has no way to model for tempature going up over time, so I just have to remember about that.