Having honed his skills in pit lanes and on racing cars everywhere, Pat Cahill was the perfect candidate for this issues ‘Player Profile’. Pat has been tuning cars of all persuasions all around the world for a solid 30 years now and what he doesn’t know about tuning probably doesn’t exist.

Q: How did you get into EFI tuning?

It was mostly out of necessity. I was taught engine building at a pretty young age so I had a good background to start with. And I’ve always been pretty good with IT stuff and electronics. Then later on when EFI started popping up in race cars everywhere, I seemed to understand what was going on with it pretty quickly. At the time, there was no real formal training, even from the ECU manufacturers, so you kind of figured it out for yourself. I went to a couple of ECU manufacturers seminars but they left me with too many unanswered questions.

Q: How long have you been tuning engines for?

EFI? Nearly ten years now. Old school carbs and distributors for nearly 20.

Q: What kind of qualifications do you need to be an expert tuner?

Firstly, you really need an excellent understanding of how an engine works and what really goes on inside one.

This is an area where everyone THINKS they know how an engine works, but few even in the professional ranks truly do.

You also need to be a bit of a physicist, a bit of a thermodynamicist and a bit of an electronics boffin. Most importantly, you must have an inquisitive mind and the ability to work through problems quickly and logically. Oh yeah, and a healthy dose of skepticism is always good too. You can never take things at face value or just follow what others do blindly.

Q: You have a plethora of experience in race car tuning. Can you tell us a bit about this and what kinds of race cars you tuned?

Mostly circuit racing engines. A lot of Formula 3, 2L Supertourers and GT Sports cars.

Q: When you tune race engines do you tune them to their maximum power for every race? Or wind them up or down for different situations?

I always tune for maximum grunt except in two circumstances. One is for economy in endurance racing. It’s amazing how lean you can run when you have a strong engine and an excellent engine management system. And losing 5% in HP to save another fuel stop is the kind of things that wins those races. However, you really want to be sure of yourself before you go and take all that fuel out of a $100K+ engine. The other is wet weather in big HP/traction limited cars. I try to make them more progressive and pay very close attention to part throttle stuff. For example, the car can actually end up being quicker in the wet with less low down torque.

Q: Have you managed to extract some amazingly high power figures from engines that you didn’t think could produce such high numbers?

I did a supercharged VY Holden ute which I expected to see maybe 350kw at the wheels from. It ended up making 497kw!

Some of the European stuff has surprised me of late. As far as atmo engines go, they aren’t too far behind Honda and respond really well to some basic stuff. We’re building a Clio Sport engine at the moment that we’re aiming for 250HP at the flywheel but I’ve a funny feeling that it will surprise us and make even more than that. We’ve used these engines in F3 and they’re pretty tough.

Q: How different is tuning a race engine to tuning a tough performance street car? Do you push them to similar tuning levels?

No. When you tune a race engine, you know straight away that the basic stuff will pretty much be constant like fuel quality and maintenance. A tough street car is normally fed whatever swill the fuel company dishes out that week (which can swing from OK to dreadful) and is more likely to encounter extremes so you never go too close to the edge.

Q: How do you rate the slew of aftermarket tuning computers on the market today? Which ones do you rate as the better end of the spectrum?

That’s really tough as there are so mny on the market. The top end would be EFI Technology (Euro then the US stuff), Pectel, Bosch Motorsport (if your running a massive budget factory backed effort!) and Magneti Marelli (which is mostly EFI Euro anyway). Then you have the mid range,which I’d say Motec, Autronic, Haltech. Then there’s the add-ons like Apexi and the numerous piggy back items out there. It’s hard to put them in any order as it comes down to what’s right for what your doing. A lot of guys are also confusing an engine management system with a fuel injection computer. One looks after your engine and keeps it running at 100%, the other just opens and shuts injectors.

Q: What was your favourite engine (race or street) to tune and why?

The most impressive engine I’ve ever tuned (and my favourite) was the Coopers Maranello. It was a pukka GT1 car with an Elanpower (Panoz) built engine. As a six litre V12 breathing through a pair of tiny 32.8mm restrictors it still made nearly 560HP at the back wheels on a Dyno Dynamics rolling road! Even Chip (Lewis, the original engine builder) was impressed with that. We put it straight in a container, took it to Bahrain and won the GT Festival in 2004 with DB and Alan Simonsen driving. The biggest achievement was running for an entire hour with only one safety car period on 100L of fuel. A lot of the big name opposition were taking it very easy, while we could run flat out on our enduro map.

Q: Any odd ball engine that you had to tune?

Any F3 engine. They have such a crazy configuration and they are really tough to get the most out of without turning them into a Chernobyl disaster. The current crop run super high compression ratios so the difference between hero and zero when you’re mapping the ignition is barely a couple of degrees.

Q: Tell us a little about the EFI University that you conduct.

Well the course was written by Ben Strader, in the USA and it’s pretty much the first and only one of it’s kind in the world. It takes a prospective engine tuner right through from the basics of engine design and operation to electronics and on to engine tuning theory and practice. The EFI101 class is a pretty intensive two days of mostly classroom lecturing with live dyno demonstrations to illustrate the key areas better. From there, you can take the EFI Advanced course which is basically the instructor and four or five other guys spending a whole day on a dyno mapping a car. It also goes into some more advanced mathematics in an effort to better understand how an ECU deals with managing the engine.

As you complete each of these courses you receive a certificate of completion. After completing the Advanced course, you are also given a dyno log which you record dyno time in. Once you have a set amount of time up, you can take the High Performance Tuners Certification exam which then classes you as a Certified Tuner, Level I.

We have also just begun to offer the “ACP” or Accelerated Certification Program, which exposes students to some pretty high tech stuff like in-cylinder pressure transducer analysis and ion-plasma technology, and also offers more than 20 hours of dyno time to each student for hands-on practice in real-world tuning..

Q: So can anyone become a good engine tuner?

I would say that anyone who really wants to apply themselves to learning the craft can become one. I think a great passion for this game is necessary. Having said that, many guys have tried, and are trying, to get to Level I, but very few have properly completed it yet.

Q: How do you rate the tuners in Australia?

A pretty resourceful and well informed bunch. We have had over two hundred tuners successfully complete at least EFI101 so there are already many guys out there who have the runs on the board.

Q: What engines do you prefer: boosted or naturally aspirated and why?

I love the torque of a boosted engine. When you get on boost you can feel every piston just shoving you forward. But then again, nothing makes the hairs on the back of my neck stand up like the sound of a high revving atmo engine.

Q: What kind of car do you get around in at the moment? Do you or did you ever own any fancy bit of machinery?

A Jeep Wrangler! Don’t worry, it’s soon to be replaced. I’ve had lately (in chronological order) an MkII Cortina GT, XT GT Falcon, EB XR8 and a Subaru WRX so my tastes are pretty varied. I find it really hard to buy a car for myself as I get to drive so many good ones that you’re always torn between different makes and models.

Q: Most of us are aware that the factory tune is always a compromise. Are there any cars out there with engines that are tuned with no compromise straight from the factory?

No, they are always a compromise. Even Ferrari, Porsche and Lamborghini compromise their tunes. They are pretty much all varying degrees of awfulness. The big problem any manufacturer faces is the impossible task of writing a map for thousands of engines that will vary considerably in their requirements, even with todays manufacturing standards. Unless the manufacturer can put each engine or car ona dyno and do it properly, then they are just making an educated guess as to what is the optimum tune. Things like knock control and lambda control were mostly developed as a safeguard for when the manufacturer gets it wrong, not as any kind of performance optimising tool.

Q: Are engine tuners on the same page world wide or are the disparities in tuning philosophies and knowledge in different places?

It’s not really a national thing, it’s a have and have nots kind of thing. Some tuners have the knowledge and the right methods, some do not. The qualified tuners in the States, Europe, Australia and NZ are pretty much all on the same page. When I went to the Mugen factory in the UK years ago, I noticed they were tuning the same way I had been, and yet people back home were telling me that was wrong. Then when I met Ben, he described his method to me and it was the same method. In my job I get to talk to some pretty serious engine tuners from some very famous racing engine companies and the top guys all do it the same way.

Contact Details:
Patrick Cahill
EFI101 Australia
T   +613-9580-6960
F   +613-9580-6994
E   pat@efi101.com
W  www.efi101.com