The opinion on the additional box-unit of the month : the APTBB4 ( BMW 330d )

Famous faces or ordinary folk, they have one thing in common: all their vehicles have turbo-diesel engines. We gave them a P-Tronic additional box-unit to try out and appreciate. They gave us their frank opinions. Because a good test is worth more than a long speech.

L'essayeur : André Delhez, commercial director, tries the P-Tronic APTBB4 on his BMW 330d

For his work, André swallows up 55,000 km per year. He is commercial director of a company which sells specialised equipment for rest homes. This father of two young girls is a regular driver of turbo-diesel powered cars. But he didn't know the additional box-unit. So no preconceptions, either positive or negative. 
Within the framework of this test, André received his box-unit by post, as do many P-Tronic clients. He is asked to install it himself..
« When you approached me to test your product and you explained how it would all take place, I have to admit to having some misgivings when I found out I would have to delve under the bonnet myself. But when I opened the box stamped with the P-Tronic logo, I very quickly realised that this would cause me no problems. The explanations were clear, and illustrated with photos. Fitting the box finally took me about two minutes »

The verdict on the road

Now the additional box-unit is connected, let's see what the verdict is on the road. André lives in the centre of a medium-sized town. So leaving his home first means joining the urban traffic. 
« With 204 bhp under the bonnet, my BMW is already pretty powerful. But despite this, I immediately felt an unmistakable difference with the box-unit. Torque was released earlier, and gave the engine even more suppleness, which is very pleasant in town »
Confirmation on the motorway
« I can't deny that the first thing I wanted to do was find out what the box-unit could do in terms of power. And I was very surprised. The extra power was such that I had to change my habits. When you regularly drive the same route, you know when you have to change gear, when you have to slow down... With this box-unit, I realised that not only could I change up more quickly, but that the extra torque meant I could stay in a higher gear, where before I would have to change down. The additional power and torque are therefore a reality, but the most astonishing thing is without doubt the way the box-unit does its work. So discreetly. You can't tell when it cuts in, or when it cuts out, it is impossible to sense the transition. It becomes a veritable part of the engine. »

What about fuel consumption?

« The first time I filled up with diesel, I realised that I had used more fuel than before", admitted André. "But I quickly realised why. Taken in by the novelty and the rediscovery of my vehicle, and wanting to test the box-unit, I drove in a different way at first. But after a few hundred kilometres I had learned how to use the additional box-unit intuitively and manage the extra power better. And the second time I filled up, I was very surprised to discover that my consumption had dropped by 0.8 litres per 100 km compared to my normal results! The entire process is really convincing! »
The test was completed by a trip to the power unit at the P-Tronic development centre, in order to put some figures to the experience André had just been through. The verdict: an extra 58 bhp and 114 Nm.  

Other opinions on our box-units:
- what the automotive journalists think
- the users' point of view

Vehicle : BMW 330d

Power:
Original calculated level: 207 bhp (152 kW)
Level with P-Tronic box-unit: 265 bhp (194 kW)
Gain de Observed increase in power: 58 bhp, or 27,63 %

Couple :
Original calculated level: 411 Nm
Level with P-Tronic box-unit: 524 Nm
Observed increase in torque: 114 Nm, or  27,49  %

Consommation :
Original calculated level: 7,5 l/100 km
Level with P-Tronic box-unit: 6,71 l/100 km
Decrease : 0,79 l/100 km, or 10,53 %

Fitted to a BMW 330d de 204 bhp, lthe additional P-Tronic box-unit provides 27,6 % of extra power, 27,5 % of extra torque, and leads to a decrease in fuel consumption of 10,5 %.

The box-unit: P-Tronic APTBB4
Type : Common rail

Functioning: Available for turbo-diesel engines equipped with a Common Rail injection system, the P-Tronic APT box-unit offers efficient and reliable increases in power. This is obtained by adapting the injection volume and time as well as the pressure of the injection rail within the parameters set down by the vehicle manufacturers.

Compatibility : Alfa Romeo JTD, Fiat JTD, Mercedes CDI, Peugeot HDI, Renault DCI.

Price : 522,75 Euros incl. VAT (if bought on-line)

The specification of the APTBB4 box-unit in the P-Tronic catalogue

Other test : François Duval, a world rally championship driver, tests the P-Tronic APT-TDCI-REX box-unit on his Ssangyong Rexton RX 270 XDI.