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New Truck Race Engine project in the making for next year competition

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Last Shake Down Dakarspeed 17/10/2021. ready for the Dakar Rally I would say.

TCM or transmission controller dos a better job now to handle the massive power of the Scania engine. It’s a 6 speed AT but first gear is not used and even 2e and 3e gear it’s very hard for the AT to make these fast gear shifts to keep up with engine RPM.


Noting comes easy with top sport. Hard work and never give up is the story behind success.

We build the fastest engines and it all looks so easy but real thing is we need to set a very hi standard and keep it there together with the teams we support.


Great job on your engines, congrats for the winnings. Looking forward to seeing the Dakar results.

Thanks for sharing

Lets talk about engine management. Not only the engine management system but as a total project.

Lets start with the ECU or ECM or just how you want to call the engine controller.

We use aftermarket ECU and there are loads manufacturers out there saying we provide the best platform. There is no best platform as we keep improving things all year in a ongoing process. It’s just a mind set that dos it all like Kaizen for example and this is what I use for processing things.

Well let’s look what is needed to gets things working for me on ECU systems. 50% is dialling in fuel for different fuel types from normal pump diesel to HVO or GTL that have a different viscosity and cetane number and this is a job that needs to be done normally begin of the year after changes by the race organisation on what fuel can be used only. The rest of the 50% are changes that involve control strategy writing new code to change the behaviour on rail pressure reading or response or torque build-up. So in all you end up with a simple 35x 2D tables and 57x 3D tables to get the job done and I customise the logic between them on how strong the power comes on. May sound strange but a less good drivers is more demanding on that parts than a multiple champion that is able to control traction and able to multi task.

Now for the fuel system. Performance by efficiency. I know I keep saying this. For an example there is this man in France that dos some lower ranking race teams and he is able to get 14% less fuel injected on the same fuelpump configuration. In fact in total he is 26% down on torque but that’s due to the different fuelpump drive we use running more pump RPM. So where dos this 14% more fuel come from?? Difference is injector set-up. We chance the valves of the injectors giving less internal leak and more accurate opening and closing of the injectors. If you bay a 100% over stock injector you know most are crappy injectors as only the nozzle hole size and maybe the needle lift is changed and you run out of fuel volume from the pump very easy and chance is if they spend some more effort on these bigger injectors you will make more clean power with a smaller injector still using the stock pump having better fuel economy.

I also know getting the correct valves made is close to impossible so on these parts we are lucky that the diesel industry is able to help us out on R&D volume rate things. Not really low cost but we are out there to be the best.

For next year ongoing build of D26A6 race engines and yes we have the order in to build one more massive power house D26E6A+ engine able to run over 6000Nm of toque. Big fuelpump and loads of modifications needed to support this fuel system. On engines like this we have to work as a combined team between companies to get these special parts.

Also to some this may sound strange is what you do and don’t do on modifications. Changes that we make on engines parts like cylinder head are very small but have a large impact on performance.

I think still the most epic looking Scania powered International Rally Truck.

Upgrades to the engine this year. Not a lot. Inconel exhaust system and a bigger downpipe and silencer to reduce backpressure. Last year exhaust system was a compromise with the team as for having no space to fit these parts and result is lower boost pressure as the ECU reads exhaust manifold pressure and reduces boost pressure as a result.

This is the part inside the injector that makes it all work. On top there is the solenoid operated valve and on the bottom end the injector needle that closes the nozzle holes. Open the injector valve and the pressure balance changes inside the injector and the needle start lifting on the nozzle end. If you fit a nozzle with more fuel flow this changes the pressure balance inside the injector and this needs to be balanced with a this part you see on the picture and this makes the injector react more accurate on opening an closing and reduces return fuel from the injector as well.

The Dakar 2022 Pre prologue is done for Team Dakar Speed. I see it as the last general test for what is yet to come. Hard driving through a pile of dust to make up for some places and we succeeded from 23rd to 12th place to start the rally tomorrow.

Day 3 of the Dakar Rally 2022. The team is getting up to speed hitting a 9e place on the rally stage today and 12e place overall in Truck class. This is top sport and if your not on top of the game your losing time.

Team Dakar Speed is a amateur team as they build the truck them selves were all other top teams have factory support or a large teams of professionals work all year on the rally trucks.

So what is the difference? For the most parts time spend on running the rally trucks and maintaining them. The professional teams knowing all systems having the routine and this is not possible with a amateur team so how can you make this work the best?

The key is keep it simple. I’m a professional engine builder and with a bit more time spend I can up engine performance and this can complicate things as more monitoring is needed for example. The team dos not have a expert on reading engine data and there focus should be get the truck ready for the next day best possible so key is to find the balance between performance and engine parts used where less is more. The good things is the Scania XPI is a very good and efficient engine and as for this year there are upgrades to the fuel system planed for truck racing and if we have this data we can implement these on the rally engines as well but as always we need to test them and for this rally truck build the coolers could be the limiting factor. We still could go up in coolant temp even up to 110 degrees C but than coolant pressure should be monitored a lot more as this shows coolant flow or coolant flow drop due to pump cavitation.

Some impression on what this rally is.

Trucks in Dakar had always been my unfulfilled dream, to compete that is. My admiration does to anyone involved.

Re. privateers not having an experienced engineer to monitor engine data, have you/they considered doing remote monitoring? In my regular life, I maintain a lot of satellite communication equipment. As a backup for access in a worst case scenario, it being full communication blackout, we utilize an L-band turn key solution, provided by Inmarsat (made by Thrane), under the name of Fleet Broadband 250. It offers voice and data, to basically any remote location in between 70deg North and 70deg South. I'm not privy to costs involved, but for a racing team it may be well affordable. Transceiver of the FBB250 is a small-ish cylindrical object, perhaps 20cm in diameter and same amount in height. Unit is made for marine environment, so it's tolerant to rocking and rolling. I think it would survive the harshness of driving through the desert.

Sounds like a plug, but it ain't, I promise. :) I don't sell the gear nor subscription, nor am I paid by Inmarsat. I just see an opportunity to share my experience, and if that helps any team competing in Dakar, I'm happy.

The point is, you could have live access to engine data, perhaps with a second or two delay, and you could support the team from your home. There are also more compact solutions, aka handheld, like Iridium (I think used to be built by a Nokia), but I'm not sure of their data capabilities. Iridium was used in the original Dakar Rally by some teams, so proven it's worth. Albeit, for voice.

Great write btw, thanks for sharing

Jump nearly go wrong Dakar Speed Rally 2022 day 4 of rally

We done it on day 4 of the Dakar Rally. From 9e place to 5e for most of the special stage but a leaking tyre throw them back to 7e place on the last part stage time for the Semi Trucks.

Overall they now in 8 piston and goal is to end this rally on a top 5 spot but this rally is very long and loads of things still can go wrong. Also take in mind this is professional motor sport with loads of teams having factory support and we are part of mixing in this game. Smile.

Still holding 9e place after half the Dakar Rally so I’m happy. Tomorrow the team has a rest day, well one day to do all maintenance needed on the truck.

Surfing the sand dunes.

The part that failed yesterday costing them over 15min as they had to slow down.


Impression on maintenance during the rest day of the rally.

To bad game over for Dakar Speed Rally 2020 after this crash. Crew is OK and they dit finch the yesterday stage on a 28e place even but the FIA safety officials concluded the role bar behind the cab needs to be replaced and the team did not have the given time to do this.

Next up is the evaluation. Engine seems to perform well but as always there is always room for improvements.

I get some question about lambda in relation to EGT. The best project we have for this to come to a conclusion is the modern Euro6 Volvo D16 common rail motor based on the 750Hp truck engine. On this fuel set-up we have plenty of fuel and we are able to smoke and run the engine from lambda 1 to over or lower than 0.88 lambda. The outcome is that these modern engines make the best power around lambda 1 and this will get the EGT up as well. The lower we go on lambda power and EGT drops as well and so dos EMP and boost pressure.

Now here is the thing if you build an engine that dos not work close to perfect all of they above can be different so take that in mind. A other very important thing is fuel injection pressure. Last year we had big problems on a race engine with fuel contamination throwing the whole fuel system off balance. No smoke no power loads of boost pressure but bit down on fuel pressure. Trick is for making big clean power is that fuel in on time getting that massive thermal spike going in the combustion chamber. If the fuel injection is extended to far due to bad constructed injector with slow injector closing time due to bad nozzle to valve balance or to low fuel pressure your combustion is more dedicated to the exhaust system shooting up EGT making good boost but less power. We use all steel pistons in all race semi truck race engines. Correct me if I’m wrong but I do not think a alloy piston will last long running full power @ around lambda 1 as things in the combustion chamber will get very hot and also last year we had a prototype steel pistons fail due to cracks and eventually on of the piston blowing a hole in the piston dome due to this. Modern diesel engines well build lean toward petrol engines if it comes to lambda numbers.

Below some pictures for the FIA 63mm air inlet restrictor plate. If you get this 63mm inlet restrictor hole working well your looking @ about 1100Hp power output so a bit of engineering needed on these parts.

thanks for your posts , always interesting

seems such a small hole to make that amount of power

what are these engines revved to ( rpm ) ?

The Dakar has been a must follow for a long time , and the trucks are a spectacle that never fails to entertain

Data tells the story. This is from a B engine so no waste gate and limited on torque as the fuelpump is on the max. We also build A+ engines with a bigger pump and smaller turbine side or better say low inertia turbo with an external wastegate and this spools a lot faster and with a good driver that makes max torque @ about 150 Rpm faster so from about 1400Rpm for a B engine and A+ engine makes max torque @ about 1250Rpm and able to make 6000Nm as the B engine can do only 5300Nm max. @ low end you can gain some power this way with an A+ engine but as you can see in the power curve it’s almost flat so this 63mm inlet restrictor dos it job well. Also note that getting 6000Nm of pulling power on the tarmac is close to impossible as only the multiple champions of truck racing can handle this as for intense traction control by accelerator peddle and from 60kmh only last gear is used and that’s almost the whole race track as you can power slide even a B engine @ 120kmh no problem but this just makes things slower so when we have to assist an new comer to truck racing most effort goes in to power management from the driver. We sometimes take 30% of the torque deliver from the engine just to make a point that the driver is slower having max engine power as track time indicates this.

As for RPM there is no point going over 2500RPM as we can only run 160kmh and that a hard speed limit but the engine has the speed governor set @ 3000Rpm.

As for next year the FIA organisation also looks for low lambda reading to prevent smoke. I do not think it will work the way they plan to take the lambda reading as it unfair for us using last generation engines that are able to make more low end power @ lower lambda numbers with no smoke @ all but as you can understand running on low RPM gives less exhaust gas volume @ that point and the rule is lambda 0.96 for 0,5 second is a penalty. So all development we have done goes to waste as the downside from a last generation engine is it runs more efficient not making a load of exhaust gas volume so these engines run a smaller turbine side with a wastegate and more low end EMP to get the job done. More EMP also makes more EGR working in the engine mainly due to the effect of turbo surge when off power and breaking going from off power to on power @ low RPM you get a low lambda reading for some time as exhaust gas speed is relative low @ low RPM. Looks when no combustion takes place exhaust gas gets trapped in the system somehow as well. we will run our test and come up with a solution for this.

Lambda reading

Torque reading

Power reading