In tuning, what are standard conditions?

Posted on August 16th, 2016 in Driving Emotion,Economy,Engine Management,Honda,testing by Julian Edgar

It’s been cold hereabouts, and I have been doing some more on-road tuning of my MoTeC-equipped, turbo Honda Insight.

(But before I get to the subject of this column, a point on the DIY tuning of programmable engine management. In short, it’s the best fun-for-$ expenditure you can ever make on a car.

Why? Because after you’ve bought and fitted a system, you’ve just gained a pastime you can do for literally ever. There is always – always! – a tuning change you can make that will cause the car drive fractionally better in a given situation, or to develop slightly more power, or to use a little less fuel.

In short, buy programmable management and you’ll never need another hobby or leisure activity!)

So anyway, this time I had the car on 98RON and there was an ambient temp of 5 – 10 degrees C.

Over the last two years I’d have tuned the ignition timing maps on this car for literally hundreds of hours. That might seem to indicate that I’m rather slow at it, but in fact more accurately reflects the statements above about gains always being able to be made – and also the fact that the little Honda is very sensitive to ignition timing variations.

As an example of the latter, it’s one of the very few cars that I know of that requires some negative timing figures if it is to avoid detonation. That’s especially the case at low revs and when only one intake valve per cylinder is working (ie VTEC is off), so giving very high combustion chamber swirl.

I do the on-road tuning of the ignition timing using a microphone temporarily mounted in the engine bay (clipping it to the throttle cable works well). This microphone feeds a small amplifier and I listen on headphones. With this system I can not only clearly hear detonation, but I can also hear the harsher edge the engine develops just before detonation.

In addition to the headphones – and the laptop on the passenger seat – I also have another trick up my sleeve. A dashboard-mounted knob allows instant variation in ignition timing of plus/minus 10 degrees.

So I drive along (lots and lots of empty country roads around here), listening to the engine through the amplified headphones. I might be at 2000 rpm, full throttle in 4th gear, the engine just coming onto boost and lugging hard up a hill. VTEC is switched on. (So that the engine will readily accept boost pressure, I have the engine switch to two-valves-per-cylinder operation from 1750 rpm upwards at full throttle. The engine doesn’t like it so much if only one-valve operation is occurring as it comes onto boost – in this non-VTEC mode, I have heard turbo compressor surge.)

Anyway, in these conditions, where change is occurring relatively slowly, I manually advance the timing with the dash knob and listen carefully. If the car clearly goes harder (almost always) and there’s no sign of detonation (or its precursor sounds), I pull over and add some timing at that spot overall ignition timing map. Then repeat the process….

Now you know why it takes me so long!

Anyway, finally to the point of this column.

As with all programmable management systems, the M400 has a base timing map (it uses RPM and MAP axes) and then a series of correction maps. These corrections include coolant temperature and intake air temp. Because, as I’ve said, the Honda is very sensitive to timing variations, I use all these correction maps.

Let’s take a look at intake air temp – and how I influence it.

I regulate intake air temp by using a water/air intercooler and variable pump speed. If the intake air temp is below 35 degrees C, the pump stays off. Depending also on throttle position, as the intake air temp rises above that figure, pump speed increases. Together with the effect of the thermal mass of water within the heat exchanger, the upshot is that in nearly all conditions of ambient temperature and boost, the intake air temp stays within the range of 20 – 50 degrees C.

Initially, I’d intended to aim at an intake air temp of around 45 degrees C (the higher temp better for fuel atomisation and so fuel economy), but I found that to avoid detonation, timing had to be retarded at this intake air temp. I then reconfigured the water/air intercooler pump map (ie I turned the pump on earlier) to aim at an intake air temp of around 35 degrees C.

So, all well and good. On this basis, the main ignition timing map would be configured optimally for 35 degrees C, and the intake air temp correction map would knock off timing as the temp rose above this.

Hmm, but what about when it is very cold, like it has been over the last few days? I’ve seen intake air temps lower than I’d ever planned – around 25 degrees. The intercooler water pump is off, but the air entering the turbo is so cold that even with spurts of boost, the water within the intercooler heat exchanger is staying at less than 35 degrees.

And in these conditions I’ve been hearing precursor sounds of detonation through my headphones.

Is it because the density of air (and so cylinder filling charge) is greater, resulting in higher combustion pressures? That is, the greater mass of air (more likelihood of detonation) is more than offsetting the colder air (less likelihood of detonation)? And so do I pull back timing at lower intake air temps (ie less than 35 degrees C) as well as at higher intake air temps (above 35 degrees C)?

And do I therefore accept that, in the real world, the engine will probably never be running the timing as specified in the main chart – after all, while intake air temp might occasionally be at 35 degrees C, stopped at traffic lights in might be 40 degrees, and down a long country road hill it might be 30 degrees – and so on…

And how do I correctly tune this intake air temp correction map? After all, to do it accurately I’d need road test ambient temps that range from -10 degrees C to plus 50 degrees C.

And, thinking about that, I have in fact tuned at the high intake air temps. Early in the tuning process, in the middle of summer and with an ambient of about 35 degrees C, I can remember doing repeated 0 – 160 km/h runs, flat out and working the little car as hard as I dared. I was tuning the high temp ignition timing correction chart (and also revising how much boost gets pulled out in these conditions – another variable!).

Looking out the window as I type this early on a Sunday morning, it’s frosty and foggy, about 0 degrees C. I should, I think, get away from this desk and hit the road for some tuning…

It’s a process that will literally never be finished.

 

Two engineering autobiographies

Posted on September 22nd, 2015 in automotive history,Engine Management,Turbocharging by Julian Edgar

I have recently been reading some engineering autobiographies relating to the early years of piston and jet engine development.

The first, The Ricardo Story: the Autobiography of Sir Harry Ricardo, Pioneer of Engine Research, is the story of the early years of life of a man who, working outside of the major automotive and aircraft engine manufacturers, made a huge contribution to the development of piston engines.

The autobiography, which covers the period between about 1900 and 1930, is especially interesting in the technical area of fuel octane and detonation. In fact, Harry Ricardo invented the concept of fuel octane rating – the resistance that a fuel has to detonation. In those days, what made a fuel effective was not much understood – to the degree that Shell was burning off, as waste, high octane fuels! Why? Because the measured specific gravity of these fuels didn’t match what was then regarded as the requirement for internal combustion engines…

Ricardo was able to physically observe detonation occurring, using windows into the combustion chamber and a moving shutter. He was the first to realise the positive implications of high-swirl combustion chambers, the first to use water injection (unfortunately not much covered in the book), and the first to build an experimental variable compression engine.

The book is written in a flowing, readable style and – for those interested in the technical aspects of his career – doesn’t get bogged-down in personal life meanderings. It’s probably best a book for those who already know something about those early days of motoring (and aircraft – the engine technology was not much different) and want to see more into a world when so much was unknown.

Another book that I have been reading is Engine Revolutions: the Autobiography of Max Bentele. As I write this, I am part way through the book – and what a fascinating treatise it is.

Bentele, a German, started his working career in the late 1930s on turbochargers. Turbos? Yes, the world’s first. He then went on to German jet engines – along with the UK’s Frank Whittle designs, again the world’s first – before the world of German engineers came crashing down in 1945 with the end of WWII.

He then migrated to the UK and then the US, working in the latter country on – among other engines – the Wankel rotary engine. It’s now not so much remembered, but US industry was very serious about the rotary engine and did much development on this design.

As I say, I am currently only part way through this book – but it is already enthralling. The non-English native language of Bentele shows a little in his prose; at times it is a bit stilted and the text more uneasily mixes the personal and professional. On the plus side, the technical detail is very high and these aspects are also well explained.

Harry Ricardo was born in 1885 and died in 1974, while Max Bentele was born in 1909 and died in 2006. Ricardo’s name lives on in the engineering consulting company that he began, but Bentele’s name is much less well known.

Two fascinating books.

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Tuning programmable management on the road

Posted on September 23rd, 2014 in Driving Emotion,Electric vehicles,Engine Management,Hybrid Power,testing,Turbocharging by Julian Edgar

Never have I had such fun when playing with a car! So what am I excited about?

Tuning programmable management on the road.

Regular readers will be aware of our Honda Insight series. As you’d expect, the publication of the articles in that series lags well behind where I am actually up to with the car. (I don’t want to run into a problem and have a big gap in the middle of the series, so it’s best from a publishing perspective that I take this approach.)

So I am around three months ahead of the series in what I am actually doing – so explaining my recent tuning of the MoTeC M400.

In the last month I’ve been tuning crank and start, fuel, ignition, idle speed control, turbo boost, exhaust gas recirculation, acceleration enrichment, wide-band closed loop feedback and lots of others.

All has been done in my shed, driveway or on the road.

It has been an immense learning curve – I’ve never before tuned a programmable management system – with some problems to overcome along the way.

But what I have found so rewarding is the degree of control that you can have over how the car drives. Tuning an interceptor (that I have previously done) or making minor tweaks to factory ECU inputs and outputs allows you to do lots of things, but tuning programmable management allows you to do so much more. (The same would also apply to factory ECUs where the software has been cracked – not the case with the Insight.)

Having so much control means that you can stuff things up absolutely mightily. I am not talking about blowing the engine (though that of course isn’t difficult with wrong timing or fuel figures) but how the car can be made to drive so badly, so easily.

Or, more positively, you can tweak and tweak and tweak until you achieve things that appear initially impossible.

The Insight is running without its hybrid electric assist at this stage, so the bottom-end torque normally provided by the electric motor is missing. With just a 1 litre engine, very high gearing (especially in first and second) and 4800 rpm peak torque, getting the car tractable around town has been no mean feat.

That’s especially the case when no ‘start-up’ map exists for this car – the MoTeC has had to be programmed literally from scratch.

The excitement of activating and then mapping exhaust gas recirc that boosted part-throttle low-rpm torque to a major degree was sensational; getting acceleration fuel enrichment sorted so the turbo boosts much more quickly after a throttle movement was fun; mapping the control of the water/air intercooler pump so that the pump works only when needed was intriguing; and designing the boost table in three dimensions to give exactly the boost behaviour I want was exciting.

I can now see better why a friend of mine years ago talked about driving to work each day, laptop on the passenger seat and making tuning tweaks at every set of traffic lights! With literally thousands of data points able to changed, and often interacting with each other in the driving, getting the perfect tune could be a lifetime pursuit.

But in the mean time, it’s a helluva lot of fun.

Wrecking yards are better than ever!

Posted on August 8th, 2014 in Engine Management,Materials,Opinion,Suspension,Turbocharging by Julian Edgar

I’ve always loved going to car wreckers, looking at the bits and pieces available so cheaply and wondering how I can integrate them into my car.

I started visiting wreckers when I had my first car – a 1973 Honda Z. That was way back in the early Eighties. I remember looking through the field of dismembered wrecks, finding dash parts from Honda Civics that I could shoehorn into the Z. I even integrated the high beam flash stalk from a Datsun 260Z into the little Honda.

Time passed, and I was then looking at wreckers importing Japanese engines and transmissions…. That led to a turbo 660cc 3-cylinder engine going into my Daihatsu Handi, and later an RB20DET turbo six going into a C210 Skyline.

I have been musing over this because in the last month I’ve been spending a lot of time back in wrecking yards.

I’m lucky enough to have discovered a wrecker of the old school, one that lets you wander around the yard of cars, spanner and pliers in hand, able to take off whatever parts you want and then take them to the front counter to have them priced.

But the big difference now is this: with modern hi-tech cars having been around for literally decades, the sheer variety of the parts that you can buy is amazing.

Need an idle speed control valve (as I did the other day)? Well, at this yard you can chose between Bosch (three types), Nissan, Toyota, Holden, Ford, Mazda – basically, every car in the yard has an idle speed control valve!

After half an hour of browsing, I walked out with a Bosch idle speed control valve from a BMW, complete with plug and a short section of loom. Cost? AUD$33.

Need a factory bracket on which to mount a GM MAP sensor? Sure – look under the bonnets of not only GM cars but also Daewoos. Cost? In this case, I was charged nothing!

Want some direct fire ignition coils? Would you like those coil-on-plug or remote-mounted? After a long look, I decided instead to go brand new with some Bosch coils – but the browse through the yard showed some very interesting approaches.

Need some 19mm hoses, preformed with bends to plumb a turbo blow-off valve? An hour later I walked out with no less than nine of them – all different lengths and bend radii. Cost? AUD$11. Oh yes, and that also included a rubber mount for the idle speed control valve that I’d forgotten to get earlier!

If you’ve not been to a wrecking yard for a long time, find a good one and have a long look around. You might be as surprised as I was.

 

In cooking chips, things have radically changed

Posted on December 20th, 2010 in Engine Management,Opinion by Julian Edgar

It’s interesting how things change. When I first started writing on the Web about cars, one area of modification concerned me a great deal – hot chips. No, not the sort you eat, but the sort that reorganise the engine management’s programming. In short, many of the chips for which people handed over lots of money simply did not work.

Back then, in the late 1990s, even the best people working in that area were simply making semi-random changes to code and then seeing what happened. The type of software available these days for many cracked factory engine management systems, where full maps are able to be viewed and tweaked in plain English, just didn’t exist. (The notable exception was Kalmaker for GM systems – literally a decade ahead of its time.)

So customers were handing over hundreds and hundreds of dollars for products that were often of no benefit. Some chip cookers retarded the mid-range timing before returning it to standard at the top end: that gave a sudden rush of power that convinced customers their cars were now going harder. Others started with a car that had been tweaked to perform worse than standard – and then fitted the original chip, so resulting in a ‘gain’. 

But when solutions for factory management problems were hard to find, and when the alternative comprised expensive, aftermarket, fully programmable engine management, chip cookers still did good business. Some were better than others: all to my mind were working way too much in the dark.

Here at AutoSpeed we sought to reveal some of what was going on by doing interviews with chip companies – interviews with Powerchip’s Wayne Besanko and also with ChipTorque’s Lachlan Riddel. Lachlan Riddel acquitted himself better in the interviews – and also had (and has) a much higher degree of technical knowledge than Wayne Besanko – but this exchange with Riddel is symptomatic of the level of knowledge that then existed in working out what parts of the code to change in order to gain a certain outcome:

AutoSpeed: A rather cruel analogy of this process [of modifying the software] is that you’re in a dark room with a large animal. You can’t see the animal, but you’re equipped with a pin. It seems to me to be an extraordinarily random way of going about learning how something – with perhaps 5000 variables – by dragging one up at a time and seeing what happens. You’re pricking the elephant in that dark room – but whether you’ve got his nose, or whether his eye you don’t know….. He yells each time – analogous to the fuel getting richer each time – but you don’t really know why the fuel gets richer. You don’t know where you’re poking the pin….

Lachlan Riddel: I appreciate the analogy….. I’ll be honest and say that off the top of my head, I can’t quickly give you a better one that more describes the process that I use. (But) if I felt as blind as the analogy that you have described, I wouldn’t start the job.

In the interview with Wayne Besanko we found that the level of technical knowledge being brought to bear was minimal; some readers may have concluded that buying a Powerchip was not for them.

However, those interviews were carried out in 1999 and 2000 – a very long time ago. In the years since, the range of software tools available to tuners has massively improved. In fact, it’s not exaggerating to say that these days the software available to allow reprogramming of many (but not all) factory management systems allows better control of outcomes than the best programmable aftermarket systems could (and can) achieve.

So when I lived on the Gold Coast and ChipTorque was nearby, I was happy to ask the company to tune the modified EF Falcon six cylinder we developed as a cheap and cheerful AutoSpeed project car. The company knowledge, the software that was available to do the tuning and the achieved results all matched my expectations.

And when, just this month, I wanted my turbo diesel Skoda Roomster remapped (it runs the VW 1.9 PD engine), I was happy to approach Powerchip. The car’s modifications will be covered in detail this coming year in a full AutoSpeed series, but the results achieved by Powerchip’s Bill Ingram, working on the Queanbeyan dyno of ESP Racing with Glen Kelly driving, were outstanding.

Together with the intake and exhaust mods already undertaken, the Roomster remap has improved power and fuel economy while retaining absolutely factory driveability. I am amazed at just how good the outcome is – I rather expected a stutter or two, or black smoke, or at least some downside. But I cannot find a single tuning negative.  In this case the tuning software was extremely effective – and I might add that I was able to watch every tuning step being undertaken, and ask Bill (and have answered) whatever questions I wished.

Two points from all this.

Have things got better in terms of tuning cars? Yes, by a simply massive amount.

And should people assume that interviews that are more than a decade old reflect current company abilities? Well, that would be a pretty dumb thing to do…

User-adjustment better than factory pre-sets

Posted on November 18th, 2008 in Driving Emotion,Engine Management,Handling,Opinion by Julian Edgar

I’ve been thinking about the way in which cars are heading. More and more these days you see driver-selectable modes. A sports mode – or even super sports mode – on a double clutch transmission. A button that sharpens throttle response, changes damping and alters auto trans shift points.

Two points.

Firstly, if the car drives badly when in standard mode, fitting a special button doesn’t fix the car. The ‘fix’ needs to be far more fundamental: at minimum, all modes need to drive well.

But the main point I want to make is this.

Why on earth are manufacturers giving only ‘digital’ control over this type of driver selection? Why an on/off switch when it would be far better to provide an analog knob that allows the driver to adjust the action of the system to their taste?

A knob for power steering weight.

Taming throttles

Posted on November 11th, 2008 in Engine Management,Mitsubishi,Opinion,Turbocharging by Julian Edgar

A while ago in a reply to another blog post, I wrote about the current Lancer Evolution that:

 

“The Evo should use far improved throttle mapping where blade angle is mapped against foot position and the calculated instantaneous tractive effort value. It should also use a smaller turbo. ”

 

At least one reader was so excited by this notion that he wished to “quietly roll up into a foetal position and rock back and forth on the floor”. However, leaving aside bizarre responses, it’s a concept sure to interest some.

 

I won’t discuss the ‘smaller turbo’ bit because most of you will have a good understanding of this idea. But what about the throttle mapping?

 

In electronic throttle cars, the relationship between the accelerator pedal position and the throttle blade opening no longer needs to be linear. In a linear system, the throttle blade would be half open at 50 per cent accelerator pedal travel, three-quarters open at 75 per cent accelerator pedal travel, and so on.

Monitoring Factory-Fitted Oxygen Sensors

Posted on September 16th, 2008 in AutoSpeed,Economy,Engine Management,Hybrid Power,testing,Turbocharging by Julian Edgar

This week we have the first in a two-part series, one that I am very pleased with.

The series is on how to use cheap and simple electronic kits to monitor the output of the oxygen sensor.

The first story I did on this, way back in the mid 1990s, resulted in the development of the ‘Mixture Meter’ kit – thousands have since been sold.

Now we both re-introduce the narrow band sensor display, updating the story to additionally discuss what many people want from such a display (and that’s improving fuel economy) and also, in Part 2, look at how a similarly cheap and easy-to-build display can be used with wideband sensors.

The latter is especially significant: while there are plenty of aftermarket air/fuel ratio meters that use wideband sensors, we’ve never seen a description of how to tap into the standard wideband sensor fitted to many of today’s cars.

eLabtronics Performance Modules

Posted on June 23rd, 2008 in Engine Management,Handling,Opinion,Turbocharging by Julian Edgar

Despite having in the past worked for an electronics hobbyist magazine, and having played with electronics for most of my life, I don’t consider myself to be any sort of electronics whiz.

In fact, I am painfully aware of how little I know and understand.

But that’s one reason I am so pleased that together with eLabtronics, we’ve been developing a whole range of off-the-shelf electronic performance modules. 

Why their need?

Well, I’ve seen it so often. Someone will ask on a discussion group or in a car club for some simple electronic device. Like, they want to automatically turn on something when a certain voltage is reached. Or they want to flash a light. Or they want a simple timer.

Always – absolutely always – there’ll be an electronics whiz that will come out of the woodwork.

Say it’s the flasher that’s desired. The ‘whiz’ will say as fast as he can:

“Oh yeah. Just use a triple-five and a few passives.”

The person making the original requests always says: “Pardon?”

Then expert says it all again, although this time faster and maybe with a URL for a circuit.

The beginner is then likely to say something like:

“OK I think I am getting it now.

“So how do I make the flash rate variable?

“And did I say, I want to pulse the car horn. Is that OK? Will the triple five do that?”

The answer of course is: no, a 555 IC won’t be able to handle the required power. And neither will it like working in a car without any protection circuitry on its power supply leads….

In fact, for every ‘simple’ circuit request, there are always – but always – complexities that are easy to overlook.

So when I say that I started working with eLabtronics over 10 months ago – and the first product is being written about in AutoSpeed only this week – you get some idea of what goes into apparently simple designs.

Of course, the eLabtronics Multi Purpose Module isn’t just a flasher. Or a voltage switch. Or a timer. The same hardware will be able to do all these functions – and plenty more – just by software changes made by the company. 

Which brings me back to the beginning. In the past we’ve covered a range of DIY modules in kit form. They were (and remain) very good designs – but the user had to build them. And many people aren’t confident or happy building electronic kits where just one, apparently trivial, wiring error can stop the whole thing from ever working.

The new eLabtronics modules are fully built and tested. Courtesy of their microcontroller design, they also have far more flexibility and options than those previous kits.

The ‘expert’ quoted above will be dismissive. But the electronics non-expert, who just wants to do all those apparently simple things, will love them….

Which workshop will be the first?

Posted on June 9th, 2008 in diesel,Driving Emotion,Economy,Engine Management,hyundai,Opinion,Power,Turbocharging by Julian Edgar

Here in Australia, major car modification workshops are generally well established. That’s said in the light of full knowledge that workshops come and go; but equally, others build a strong reputation and live on for decades. Some even span two or three generations of the one family.

 

I know that you can always find customers to denigrate any workshop, but places like Turbo Tune in Adelaide, Nizpro and Beninca Motors in Melbourne, MRT in Sydney, ChipTorque on the Gold Coast, and Romano Motors in Brisbane are longstanding workshops with good reputations.

 

And I wonder which Australian business – either these or others – will be first: the first to realise that there’s money to be made in specialising in a new-age of car modification.