The Stories Old and New.. Diesel's and A.F.R's the only way to tune...
Dynomotive Established 1976
So there we are, sitting at the table in the middle of nowhere in South Africa with eight other guys, the windows are all open to air, it was about 28 degrees at the time and the landscape surrounding the building is what I can only describe looks like a red brick quarry, the bar is fully stocked with everything you can imagine, (Including Rob’s long time favourite beer Castle Draught, this by the way taste’s better then Carton Draught). Having said that I am sitting at the table nursing a tropical juice as is Rob.
It feels like a very odd place to have a business meeting let alone an office space, but this is very important in fact the most important part of our business trip. As we break bread (I don’t mean this in the literal sense we actually had Braai Lamb and roast potatoes with strictly no salad.) introductions where done and some of the history of Rob and I was laid on the table…. This is the first part of an ongoing story….
(This is a story I knew off the top of my head and by the end of my trip to give you back ground.) Robert Rapisarda, (Unichip’s Dyno tuner and technical support manager.)
He would start the story by saying. “I remember when I first visited South Africa in the early 90’s” (South Africa in the early 90’s was a totally different country to the one I know.) Rob’s old work place had a contract selling turbo kits directly to Nissan South Africa for the Navara Diesel. But as part of this deal Nissan were required to put a dyno in there factory for dyno tuning and testing of every Turbo diesel kit they fitted.
At this point they were thinking of selling them a local Australian delivered dyno to get the guys at Nissan out of trouble, but they thought “why not look local first, it will save freight and cost them much less.”
This is when the C.E.O from Nissan (who I’m told is a very relaxed likeable guy) took Rob to a local service station that built dyno’s. (Where a very “switched on” guy work’s.) This service station it was built on a hill and due to the incline of the hill it allowed for a very small workshop underneath the shop front.
“It was one large roller, picture two dyno’s placed side by side, that could have one car jacked up and the other on the rollers so you never lost time from moving cars in and out while you removed the carbys and changed the jetting.” (This double Dyno was designed and built by the service station owner.)
Rob stuck his head into the window of a car and noticed that the tuner was using a rough version of what we now call the “Unichip tuning pots “. Rob asked the tuner what it was and how it worked… he was told “This? I just made this to change fuel mixtures and so I could manipulate timing, for fuel injected cars. It’s not as easy to tune as a carby” (The main reason there is such a high demand for tuning cars in Johannesburg is the fact that its 1450mts above sea level.) It was with his next breath Rob said, “bugger the dyno we need to get this software and that Chip.”
Not too long after this the very first version of what we have come to know as the Unichip was back in Australia on a brand new 80 series Petrol Toyota Landcruiser, this was no ordinary Landcruiser it had a Turbo bolted to the side of it and the Unichip was the exact cost affective answer Rob was after to manipulate the timing to suit the boost and get the fuel mixtures perfect to suit this one of vehicle!.
This is of course how and why Unichip got introduced to Australia, to give customers the perfect tune and result for their pride and joy…
(funny how I tall works, people are the same, the manufactories are the same, internal combustion engines are the same and the customers are the same… the only real difference is the Unichip and how advanced it has become with well over 2 decades of R&D gone into the Unichip version Q4.)
Most of the guys at the table didn’t realise Rob’s involvement with Unichip had spaned so may years, the others who did know, it was like seeing an old friend. This is what helped ease into the next topics of the meeting.
As I clear my plate of lamb and serve up another portion of potato’s I did realise this was something very unique, everyone sitting at this table had one common goal in mind. (Keep in mind, different country, different language and different culture.) We all wanted OUR customers to have the best product.
(You don’t need to hear me rant about this again, by now if you have read my blogs you know the benefits.) It was sincere and hand downs the best business meeting I have ever been too.
Taking all of these positive points back home with us by the time we had landed it was only 7 days out from our Unichip training seminar. So needless to say we had our work cut out for us.(The rundown on the training day can be read here.)
This next story I have heard so many times, but always at the Unichip training, it’s his introduction and never alters from the truth….
Now the Unichip gets its history from Petrol but is very well adapted to diesel, (The fact is it can be used on any Fuel Injected vehicle, no matter if it’s L.P.G, Petrol or Diesel. This is what brings us to our second part of the story…. Dyno tuning Diesel’s with an A.F.R Meter (Air Fuel Ratio).
Rob Rapisarda started tuning Diesels Using air fuel ratio as the reference way back in the 90’s when it was considered the only way to tune a Diesel was off E.G.T and visible black smoke.
Now to some this may seem like a massive claim to fame, for us it’s Fact and something we accept every day.
One of the opening lines to our Unichip Training days is in direct relation to tuning to A.F.R’s when doing diesel tuning. Now I’m sure in the mid 90’s when diesel tuning was becoming more popular that there would have been more than one person playing with AFR’s and working out what the best Ratio is for a Diesel engine. (I would like to think that it happened all at the same time, different people coming up with different Idea’s and pushing the limits, there was no internet, no Facebook or blogs, it was single people working by themselves trying new techniques that gives us the back bone of Dyno tuning we see today, and I am lucky enough to work with two of the best in the country.)
So back to Rob and A.F.R tuning as he address’s our Unichip agents from all over Australia, “ I tried tuning using EGT and visual black smoke as it was done in the early days. But it didn’t make sense, it wasn’t precise, and temperature doesn’t feel like a solid basis to put my stamp of approval on.” The other issue with EGT is what number is considered “safe” for all the different diesel engine designs and manufacturers. Where do you measure EGT, pre- turbo, post- turbo? All these factors have a huge bearing on what EGT you measure. Then you bring into the equation of Injector timing and this can have a huge impact on EGT’s without touching the fuel.
Rob came from a Petrol tuning background where measuring Fuel mixtures with Co analysers and
Air Fuel Ratio meters was a standard practice from road cars to race cars. He tried measuring diesels with the same equipment that was used on petrol vehicles but soon realised that the equipment was not up to the task for Diesel vehicles.
So Rob approached Motec Fuel injection first who made aftermarket fuel injection computers and AFR meters. To see if he could get an AFR meter built that would read leaner than 20:1 Air Fuel Ratio. This by the way is very, very lean for a Petrol vehicle. (Typical AFR for a Petrol engine is 12:0-1 to 15:0-1 )
Rob ended up working with Autronic to build a meter that would read from 9:0-1 to 36:0-1.
The rest is history as Rob soon had data for all Australian delivered diesels and a baseline AFR reading was achieved. These meters were then supplied to Tuners around Australia and the world so they could tune Diesel vehicles a lot more accurately.
Below is A.F.R scaling: (Just so you have an understating of what I’m typing about)
15:0 – 18:0-1 for Max Power (Depending on engine and Injection design)
25:0 – 30 + for Cruising
This was a big jump for Diesel tuning worldwide, a lot of costs were involved but Rob kept faith having the knowledge that diesel did run lean he just didn’t know how lean... At last Tuners had a tool which could measure Diesels for correct and repeatable tuning purposes.
I feel, (and yes, it’s my opinion) that these two stories are two of the most important pieces of history in the Diesel aftermarket industry, and have influenced so many other methods of tuning around the globe.