One major concern that we do hear a lot around the traps is that people have had their vehicle “custom dyno
tuned”, but the person who did the “custom tuning” just came out to their house, or to their work, and loaded a
tune file into their ECU in the driveway or carpark.
So, in our industry, this is commonly known as a “Load and Go” tune file or a “Carpark Tune” – and one of these is
absolutely NOT custom dyno tuning your vehicle…
Although the people who supply these “one tune suits all” mass-produced files will state otherwise – this is because,
initially, it would have been developed via the use of a dyno, but on another vehicle and most likely in a different
country. But no, this is not the case, it most definitely is NOT custom dyno tuning – as every engine is different and
every vehicle is different. Factors such as fuel, ambient air temperatures and barometric pressure differences;
different engine tolerances; different vehicle usage; different vehicle weights and setups, amongst other things.
Therefore, every tune should be different and this method of “one tune suits all” (which is not the case!) will give
you far inferior results over a proper custom dyno tune in every way, from power and torque gains and fuel
economy improvements to engine reliability plus more.
The only way that vehicles can be PROPERLY tuned, is via specialised equipment and software and the use of a dyno,
which will provide accurate and consistent data that is needed for precise tuning. The Engineer makes custom
changes to the parameters of the standard tune file within the ECU. This is a complex procedure, which is performed
to suit each vehicle individually and specifically.
Here is a classic example of a “Load and Go” tune file versus a custom dyno tune by our in-house Engineers. It’s a 79
Series LandCruiser, 2023 model. The owner of this vehicle came to us because he recently had a “load and go” file
loaded into his ECU at his house by a mobile “tuner”, however he didn’t feel like his Cruiser had the “go” that he
thought it would have. Which is not surprising to us at all!
The other thing he noticed was that his factory clutch started slipping, after he had it “tuned”. When questioned on
this topic, the person who installed the “Load and Go” tune file told him that the vehicle didn’t need to have a clutch
upgrade carried out. This is also incorrect information – the factory clutches in all the 70 Series LandCrusiers (and
most other manual diesel vehicles as well) are very weak and will not handle any extra load due to more torque from
a tune. It’s a non-negotiable for a clutch upgrade to be carried out for every 70 Series LandCruiser that we custom
dyno tune here at Ultimate Diesel Tuning, and we tune several of these per week.
When this Cruiser was presented to us, the first thing we performed was a full inspection of the engine to ensure
that no engine damage had been caused from this substandard tune. Luckily, for the customer, it was ok at this early
stage. “Load and Go” tunes can have negative and disastrous impacts on the engine, in the short or long term, we
have seen it happen many times before.
We then performed a clutch upgrade to the 79 and then carried out a proper custom dyno tune to suit the vehicle,
its modifications (it has a stainless steel snorkel fitted, an upgraded exhaust system and huge 35-inch tyres) and
what it is used for (daily driving, relatively heavy towing, plus offroad and beach driving).
Let’s look at the results. The power and torque figures from the “load and go” file, which was how we presented the
vehicle on the dyno when we first ran it up, were:
121 Kilowatts of power and 415 Newton meters of torque.
We then put the ECU back to standard and ran it on our dyno again – in standard form this Cruiser made:
96 Kilowatts of power and 320 Newton meters of torque, at the rear tyres.
This means that the “Load and Go” tune file only made a 26% gain in peak power and a 30% gain in peak torque (just
under a 100 Newton meter gain), which is a very disappointing result. The owner was 100% right, he really was being
gypped with the file he paid for in this vehicle to get it tuned.
After our Engineers completed the full custom dyno tune, the Cruiser then produced:
142 Kilowatts of power and 637 Newton meters of torque!
This equates to a 48% gain in peak power and a 99% gain in peak torque! We achieved 17% more peak power and
53% more peak torque than the “Load and Go” tune file.
So, the outcomes were that the “Load and Go” tune file was very conservative, it wasn’t correct for this vehicle, and
it didn’t maximise the potential of this vehicle. In summary, the vehicle wasn’t tuned correctly. Now, the 79 Series
has much nicer and smoother driveability and a lot more power and torque across the entire rev-range. The
customer will enjoy fantastic reliability as well, and the upgraded NPC clutch’s pedal feel is very similar to factory, so
nice and light.
AND, on top of all of this, the customer paid almost the same price for the “Load and Go” tune file, compared to
what he paid for our custom dyno tune, which was completely customised to his vehicle by our in-house Engineers
via our dyno.
So when it comes to the choice of a “Load and Go” tune file or a proper custom dyno tune, which will you choose?
For further information, give us a call and speak to our diesel experts.
