VDJ Piezo Injector Tech.







With the introduction of the "Facelift" model of VDJ200R in late 2015 and on the same era VDJ70 series, some mechanical updates were done for improved emission control. These were the first models to arrive with Diesel Particulate Filters (DPF) on the exhaust. One of the other changes was the introduction of Piezo injectors. Since this introduction there has been much conjecture in the market place as to effect DPF has on reduction of power and its long term viability/reliability. Much myth has been created...


What is a DPF and its function? All diesels produce particulate in their operation. This particulate is a known carcinogen and in the interests of public health, legislators around the World have brought in laws to minimise it's introduction into the environment. How does a DPF function? Basically it captures the particulate and then via pressure monitors and some clever modelling, it does a high temperature "burn" to clear the "soot" turning it to ash. The inert ash is then passed out of the tail pipe under exhaust pressure. Build up of ash in the DPF will also shorten it's service life. But nowhere near as much as soot.


It is well established by the Engineers at Toyota that there can be injector spray pattern issues with the late injector. They have been able to trace it back to water from combustion on cold start being brought back into the cylinder via the Exhaust Gas Recycling (EGR) system. This water sits on the nozzle tip when the engine is shut off on cold running and damages the nozzle resulting in a poor spray pattern. Now what does this have to do with the DPF? Well the enemy of the DPF is soot from incomplete combustion. It won't show as a poor air fuel ratio or the like but as extra particulate that the DPF has to catch and deal with. The out come of this extra soot is extra high temp burns. Those extra high temp "burns" to clear the soot then destroy the catalyst in the DPF and it loses its ability to capture soot. First clue that there is an issue is soot in the tail pipe that has come past the DPF. Basically at this point the DPF is failing and not able to function. IF you have a soot level in the tail pipe of your DPF equipped VDJ, get it back to Toyota regardless of age. There is a service bulletin out on this matter and the injector, DPF and EGR calibration will be repalced if it is deamed to be outside service limits (any soot in the tail pipe is outside service limits!).Is this a failure of the DPF? NO! It is a result of the compromised injectors! That is a fact missed by many in the aftermarket industry...


SQP works on many different DPF equipped vehicles. It is our challenge to work with the technology fitted and calibrate to higher levels of power WITHOUT compromising the function and service life of that tech. One thing that became very clear on VDJ early in the piece was that there was an issue with injectors over earlier non DPF models. With vehicles being presented for recalibration after having the DPF removed by other operators, it was evident that some cars were just straight out DIRTY! EVEN BRAND NEW FROM THE FACTORY! Comparable AFR ratio from earlier pre DPF VDJ saw these cars sooting to a level that wasn't accptable. Taking fuel back out of the calibration simply took power away. Even with factory fueling calibration levels it could be seen that some cars were DIRTY! Was it at a level that was an issue to Toyota? NO they have particulate filters to REMOVE that soot. It is only one the DPF is removed that the injector issue becomes clear outside those that are so bad that the DPF can't cope.


SQP had sought a solution to this issue for some time. After that long introduction we are please to say we have the product now available to solve the sooting AND give great power gains at the same time! As with all things SQP bring to the market, extensive testing has been underway on not only the dyno out put but also full drive circuit. We have been fortunate to of had one of our customers VDJ200R for some time to do this testing on. This vehicle was one that had presented for work on the calibrations some time ago. It was a 'dirty" car on the dyno and disappointing with it's power output as fuelling had to be compromised to keep the street somewhat clear. No better car to test on than one with the issue we are trying to solve! The results? OUTSTANDING!!! Read on!



The hard thing with Piezo injectors is a new "nozzle" simply can't be screwed to it like on earlier models. The design of this nozzle is critical to acheive a "clean" spray pattern and even flow across the engine. All SQP injectors are flow tested before being fitted. No chances! The nozzle is a clean slate design with a improved spray pattern the goal. Not a honed OEM variation. But we didn't just want the same power protential, we wanted to SOLVE the soot AND get some more POWER!


So the day came to change out the dirty injectors. Injectors are all that were changed. 160000km OEM factory turbos left on. Standard factory airbox. Safari snorkel. MANTA Twin 3" into single 4" exhaust system. 33" tyres.




And onto the dyno it went. Now the graph below takes some explaining... we will refer to them as ORANGE, BLUE, PINK, RED and GREEN.



We will start with ORANGE. This is the power this vehicle made when it arrived at SQP. We flashed a calibration into the trans controller that held 4th gear and kept the converter locked on the dyno. This is to enable more accurate readings before and after as slip is eliminated as is torque multiplication through the torque converter. It can be seen from the AFR and the power level that the past tuner had been trying ot stay away from a dirty burn. With AFR that lean there was penty of power left on the table. SQP retuned it and gained the power shown in PINK and BLUE. But the car was sooty. There should never of been the levels of soot we were seeing at 16.5-17.5:1 AFR as measured on the SQP WEGO Lab grade Lambda meter. It indicated the injectors had a spray pattern issues. This is confirmed with the runs after the SQP Plus 28% (SQP will market as PLUS 30 as that is an established update in earlier VDJ) injectors are fitted. Some careful calibration of the injector at UNCHANGED BOOST LEVELS ustilising the OEM turboes, POWER UP by a WHOPPING 65hp! And super clean out the pipe. The gains in torque? OUTSTANDING!



 Now the Dyno Police are doing to be reading this and running around with their self serving drivell on how a VDJ200 can't have power readings taken on a 2WD machine and the likes. SQP has only ever sold GAINS! We have NEVER sold a power number. That is true for the last 20 odd YEARS that gains have been quantified on rolling roads via SQP. Back in the early 90s we just went ot the drag strip but that really isn't a true indication of what the 4X4 market is after. To counter the hysteria we went to an independent dyno for some power runs. We chose a hub dyno. WHY?? Because all the modelling that is used to come up with an inertia factor as used on rolling roads is eliminated. These models are flawed (even more so on 4X4 dynos) when tyre size (and resulting weight) roller interaction etc can vary the power readings- but not the BEFORE AND AFTER.  Running 1:1 through a locked converter, what is read at the hubs is as PURE as can be done. Do you think Toyota engineers use a 4WD to calibrate their engine? Nope...ENGINE DYNO!



 So how does 382hp at the hub sound??? Oh and a whopping 892nm of derived torque!


Now we made mention earlier of how CLEAN this thing was at the indicated AFRs. This ticked the box on the soot issue from poor spray pattern as we were able to burn near 30% MORE fuel with the SAME air from boost we had before injector change. How clean? Well take a look at this!



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But then that got us to thinking (whch is always dangerous and time consuming) with all the claims that SQP hasn't seen substantiated that the DPF is a massive flow restriction and impediment to power production, we set about getting some DPF back on this turbo back car and the data. Straight forward type deal and we were able to retain twin 3" to single 4" but in a DPF back configuration.  Just how restrictive are the DPF? After some careful mapping...Check it out!!




We were able to make to within 8HP of what we saw with a twin 3" dump either side. There are many reasons why this injector is able to give these awesome results and none of them are new to those that understand how diesel injection calibration works in its truest form and fundamentals. It is often misunderstood that richer fuel mixtures are an indication of abundant fuel from longer injection times but it is really only an indication of incomplete combustion. How did it go torque wise??




OVER 850nm at the wheels! Sure it lost near 25nm over turbo back but emission complete power at the level shown here? Yep we can spare the 25nm!! With how clean the exhaust is and lowered fuelling levels we don't expect that DPF will have a lot to contend with in comparison to the OEM dirty burn!


SQP is truly excited to be offering this injector upgrade for  the Facelift DPF equipped vehicles. They have always been a lower performer from the factory after mods than the earlier models. This injector upgrade is a complete game changer. Combined with ever further refines SQP leading transmission calibration, this truly takes the Facelift VDJ to a new level. No turb upgrade. Standard factory air box, DPF back exhaust upgrade and over 100hp over factory on tap? Bring it!!!

VDJ70 series guys feeling left out? We have some testing coming up for your rigs soon! This is going to be exciting!!


So How Much???


This upgrade is exceptional value.


FLOW TESTED Injectors supplied exchange and fitted by qualified tradesmen including SQP leading Engine and Tranmission Calibrations on VDJ200RRRR;




You are already and existing SQP customer and have our Industry Leading calibrations on board? We are offering a GENEROUS 10% discount to you!