Teemu Peltola’s smokin’ diesel powered drifting Mercedes Benz

Images of Teemu through the ages – a 10-year throwback to where it all began…

Looking something like a road going steam engine throwing out pillars of BLACK SMOKE is Teemu Peltola’s Mercedes Benz w203.5 drift monster. In action here at Gatebil Mantorp Park in Sweden as featured in the Grumblo Car Builds Series.

Video: Teemu Peltola’s OM648 powered Mercedes Benz w203.5 at the June 2017 Gatebil Mantorp Park

Teemu is the driver of Black Smoke Racing. Based in Kokkola, Finland, this group of diesel engine nuts are known for their own way of doing things. Either in developing their diesel power plants, driving a Mercedes estate car (or station wagon) drift car into top ranking positions in international drift races or especially having fun while doing all of this. It’s not common or easy in any way to take a diesel engine and turn it into a race prepped power plant. So Black Smoke Racing haven’t exactly made life easy for themselves during their 10 year journey. As they state on their website.
blacksmoreracing.com

The Black Smoke circus started out with a Finnish guy who wanted to try drifting with a diesel car, this struggle has remained the same for years. Black Smoke stands for doing your own thing, no more, no less.

Going into any drift event in Northern Europe you will always see plenty of BSR (Black Smoke Racing) branded apparel worn by a wide range of audiences. This could be BSR in a nutshell, however we didn’t want to stop there so we sat down with Teemu himself to discuss the current and previous iterations of the car and their various technical evolutions. We’ll begin with the Mercedes W123 wagon powered by a Mercedes OM606 3.0L turbo diesel. And we’ll list the engine evolutions roughly in chronological order.

A single Garret turbo with diesel pump modifications on the stock OM606 engine gave around 500 hp with 3.8 bar of boost. The engine was revved up to 6500 RPM which is about 1.5 times the original revs! Teemu tells us that the wide RPM range was to his liking, but the old style prechamber diesel unit is not really designed to perform under heavy loads while drifting and so proved to be a bit problematic at times.

Not to make life too easy for the drifter, in the next evolution they added an Eaton M90 Supercharger and a Holset HX52 turbo to boost the OM606 together. This produced around 550 hp and they then began to experiment with Nitrous Oxide (NOS) in this same crazy combo!

The supercharger produced a lot of low end grunt but at the same time it was limiting some power from the higher RPM range. To make the combination work the guys needed to create some boost controlling valve techniques. However the valves suffered failures due to the extreme heat produced by all the components and direct contact with exhaust gases.

Around this time in 2013 they also upgraded the Mercedes chassis to a newer W203 C-class model.

The supercharger was removed in the third major engine evolution and replaced with massive amounts of NOS accompanied by a Holset HX52 turbo on the OM606 diesel motor. This was clearly the best setup for Teemu and his driving style. They began by controlling the NOS feed to the engine between a boost range of 0.2-1.5 bar. Pretty soon the hunger for power hit Teemu so hard that he removed the lower and upper limits for boost and the Mercedes became a full on rocket 🙂 No turbo lag whatsoever, just pure fun! This combo produced around 700 hp with NOS and full boost of around 4 bar.

They still remember how easy it was to drive because of the instantly responsive engine and in fact they won races using this combo. The downside was of course the NOS consumption which was off the charts (being force fed all the time in the engine) and the constant need to change the NOS bottles in order to have the car working as needed. And the use of NOS was not so well received in all countries where they wanted to race so they needed to come up with another plan…

All hail the “SUPER STROKER” engine as referred to by the guys from BSR. I remember following this build myself with great interest at the time. This was the most customised engine so far from the guys and included all the crazy ideas they had gathered from the previous evolutions of the OM606 diesel engine. Just think about some of the specs. A stroked engine up to 3.4L with custom billet pistons which were mainly designed in house. And Cummings direct injection style injectors fitted into the old prechamber Mercedes cylinder head. A compound turbo system with a Holset HX40 Super turbo feeding into and waking up the monstrous Holset HX60 turbo.

This kind of compound turbo arrangement is also referred to as “staged” since there is a waste gate between the turbos. Sadly all of this custom work meant that pretty much everything needed to be built from scratch by these pioneers in diesel drifting. And this is where some of the challenges arose such as the diesel fuel timing under high boost and RPM conditions with the centrifugal style timing controller inside the diesel fuel pump. To put it simply the boost pressures in the diesel pump were greater than the centrifugal forces needed in the pump to keep up with RPMs. They tried stock and modified parts inside the pump but soon came to the conclusion that the whole diesel timing system should have been redesigned from scratch and the “SUPER STROKER” OM606 engine was then put on hold.

Teemu remembers that about 4 or 5 Holset HX60 turbos were destroyed during their attempts to control the diesel timing. Sadly this combo did not see a lot of real action but it really had good potential. The low end power was really good in this setup as there was already more than 400 hp at around 3500-4000 RPM which was unheard of at the time with these kind of diesel builds. Teemu tells us that this monster of an engine could be put back together if they managed to get a hold of a crankshaft from a Mercedes W140 350 Turbodiesel. *So IF you happen to have one, let them know! info@blacksmokeracing.com

The compound turbo system from the “SUPER STROKER” engine was used in a stock OM606 engine with some good results until the guys saw the future with CDI engines. In 2015 BSR started to experiment with an OM648 engine that came out of a damaged Mercedes Benz W211 320 CDI. Switching to this diesel motor also meant changing the fuel injection system from a mechanical to an electronically controlled Common Rail Diesel Injection (CDI) system. This would offer better control of the fuel injection volume and timing via ECU software providing higher power and efficiency. And the fuel injection pressure would be up to ten times higher at 1600 bar, up from 170 bar.

Given that the new OM648 diesel engine was also 6-cylinder and similar to the previous OM606, the engine mounting would not be an issue. And to make things work they decided to retain the stock Bosch EDC16 ECU that came with the engine. They began by stripping out the wiring harness and using custom controller software. With little knowledge of this particular system they had to get things running utilising temporary wiring and the ECU, ignition, steering and gearbox controllers were all still in place. Which was necessary to get the immobilisation system to allow the engine to start.

They then decided to strengthen the engine block with a 10 mm thick custom griddle plate, which required adding some length to the oil pump chain and hard bolts from ARP Bolts to secure the connection rods to the crankshaft. And they were hoping they would be able to retain the original connecting rods. The original high pressure fuel pump (HPP) wouldn’t be able to maintain the chosen pressure levels if they were to increase the volume of fuel going into the engine so they added a bigger customized HPP from a Mercedes Benz 400 CDI. This would allow bigger fuel volume at the same pressure allowing for 30% more fuel through the injectors without affecting pressure. And via the custom ECU software they were able to get the maximum pressure from 1600 up to 1800 bar.

Getting the fuel injectors to function above 350-400 hp required some modifications (by Rengaspalvelu Karjalainen in Finland) allowing for 110% more fuel flow than the originals and enabling a power increase of up to 400 hp and beyond. During testing they discovered that the ECU software was limiting the fuel flow when boost kicked in so some specialist software modifications were required along with a bigger boost pressure sensor. Compound turbo systems were experimented with in the CDI engine too before moving into one gigantic Holset HE551V variable geometry turbo from an Iveco 14L truck.

Variable geometry turbos essentially function like a smaller turbo at lower RPMs and as a bigger turbo at higher RPMs. A set of adjustable flaps are controlled by a vacuum allowing the turbo to operate in the best possible way in variable load conditions. This turbo has nowadays a billet compressor wheel to handle the stress of 4.5-5 bar of boost. To allow more air to enter the combustion chamber Camshaft Works in Finland upgraded the cams with a little more valve lift. This combination on the 3.2L diesel engines pushes out about 700 hp and 1000nm from the engine. That’s 3.5 times the original horsepower and double the torque!

A totally separate article could be written concerning the software issues and their adventures in developing the CDI system for over 4 years. The latest news is that with some outside help the guys were able to identify and remove bugs in the custom software. Now they are extremely happy with how the engine responds to the driver’s requests of turning the rear wheels into a cloud of smoke. This development took a good turn just now at the end of the 2019 season, but since no racecar is ever ready the next planned step is to focus on a fully custom diesel race ECU by NIRA Dynamics in Sweden and to slowly get rid of the highly modified stock Bosch ECU.

Finally we come back to the present and some details on how the car currently is. A Mercedes Benz W203 wagon facelifted using W204 front end parts along with whole rear corners to get a more modern look, so hence the name W203.5.

The engine is currently the OM648 3.2L straight six turbo diesel paired with a Quarter Master triple plate clutch and a G-Force Transmissions 4 speed dog box commonly used in drift and track racing applications in the USA. The rear end is from a MK4 Toyota Supra merged into the stock Mercedes subframe.

I’ve got to hand it to these guys after about 20 engines and 15 turbos later they still are doing their own thing. Like they say on their website

The clothing line is made by us, like the motorsport part, probably not in the easiest way. Don’t do what you do best, do what you like.

A big thank you to Teemu, Patrik and all the guys at Black Smoke racing from Anssi, Davy & everyone on Grumblo.com for taking the time to share the story of their journey with us!

To stay updated with Teemu Peltola and Black Smoke Racing’s journey, make sure to follow them on:

Facebook – Black Smoke Racing & Teemu Peltola

Instagram – blacksmokeracing

Photo Credits:
Black Smoke Racing, Janne Tuikka, Juha Klemola, Kari Koskinen, Jerker Jokiniemi & Photography by Mogge