After 5 years, 2 Dutch Grand National titles, 3 Euro Cup and 2 European Championship titles in the 2.5t/5500lbs light modified class, the Screamin' Bobcat Pulling Team from Ijsselmuiden in the Netherlands did some major changes on their light mod tractor called ''Wicked Screamer'' during the last 16 months. After the great success in that class from 2015-2019 and some not very big changes, it was time for some bigger changes and improvements to keep the tractor competitive for the future. Already in 2018, the Dutch team started on the Wicked Screamer with a clockwise and counter-clockwise turning engine. That setup worked pretty well and brought them the Dutch Championship and Euro Cup title in that year.
After the Indoor pull in Zwolle last year, the team started to work on the light mod and changed the whole front end of the tractor for the new setup. The main focus on those changes was the weight distribution and less twist in the Domex chassis. After all the CAD work and calculations were done on the computer, the team started to work on the chassis and the new components for the drivetrain on the Wicked Screamer.
The position of the 2 Sassy Racing V8 Hemi engines on the chassis was completely changed.
In the past, the positions of the engines were lower and further apart. To have more weight on the front end for a better balance, the Screamin' Bobcat Team moved both engines more forward and further in the middle of each other.
The engines sitting now almost on the front end of the chassis. Due to this change the engines also sitting higher on the chassis now. Due to the new position of the engines, the whole front end of the tractor was completely new rebuilt. Due to the less space on the front end now, there was no place anymore for the old fuel tank on the front end. But that problem was solved, with 2 new aluminum fuel tanks on each engine.
The fuel tanks sitting now on the back of the engines, like on their heavy modified tractor called ''Bobcat Sr''. Nothing has changed on the position of the oil tanks for the dry sump lubrication, they are in the same position on the engines as before. Due to the new position of the engines, they also had to build new engine and weight brackets, plus a new front axle with new front wheels.
All the parts for the new engine and weight brackets were laser cut and bent by their sponsor Tosec BV in Zwolle, the Netherlands. The new front wheels on the tractor are a set of Vredestein V64+ tires on aluminum rims. Those wheels were usually used on agricultural machineries, like on rotary rakes. The wheels are much smaller and lighter compared to the old ones.
First, they wanted to drive with a set of Trelleborg front wheel tires but they were too small and too hard to turn with the weight of the tractor on them.
To the drivetrain: Because of that position changes the tractor also needed some new components in the drivetrain. The largest part in that was the crossbox. Due to the narrower side by side position and higher center of gravity of the power plants, the old crossbox of the tractor didn't fit to the new setup anymore. So the only possibility was to build a completely new crossbox for the tractor. The new crossbox, bases on the crossbox of the 4 Hemi engine-powered Bobcat Sr, which was developed in collaboration with Bennie Vreeman of Vampire Gears from Neede in the Netherlands. Berrie Boer developed the new housing for the crossbox on CAD and Bennie Vreemann did all the calculations for the new crossbox.
The new aluminum housing for the crossbox was CNC-milled by Breman Machinery in Genemuiden. The Dutch company also has machined all the previous crossbox housings for the Screamin' Bobcat Pulling Team in the past. After the housing was ready, the new crossbox was fitted with brand new custom-built gears. The new gears were developed and built by Bennie Vreeman of Vampire Gears. Also on the crossbox were again mounted those little Vampire Gears reverse boxes. Those reverse boxes worked pretty successfully on the tractor before. The team uses those reverse boxes since 2018. With this setting, they can take the torque out of the chassis, which makes the tractor is more stable on the track and they also can bring the power of the 2 Hemi engines better to the ground. Also, the new driveshaft from the crossbox to the rearend was built by Vampire Gears.
Last but not least both Hemi engines were completely dismantled and overhauled during the last winter.
Already after the 2018 season, they have switched the setup of the engines for the 2019 season. The Screamin' Bobcat Team replaced the old Veney Hemi cylinder heads for new bigger BAE Hemi cylinder heads. The new heads worked great, made more power and the engines were more reliable.
For 2021 the team completely re-worked the fuel systems so the new engine setup even got better performance, this was also a test setup to see things worked out like they hope to. That means now they can easily adapt these changes setup to Bobcat Sr and the mini modifieds.
After all those changes the team hopes to have a better balance and less twist in the chassis for the future. The first run of the rebuilt Wicked Screamer was on the 24th of July 2022 at the Superpull in Brande, Denmark. The new setup worked pretty well, but in the end, it wasn't enough for the win in the light mod division. The Screamin' Bobcat Team went home with a nice 2nd place, behind Gators with Patrick Hansen behind the wheel from Denmark. But at the next pull in Made, the Netherlands they turned the table again and won the competition there. For the last 3 rounds of the season, the Wicked Screamer received a set of new cut puller tires. The old Firestone Puller 2000 HP tires were replaced by a set of new Mitas Powerpull 30.5x32 tires. The new tires worked pretty good on the tractor and another win at the Dutch championship finals in Langedijk brought them the Dutch Championship as well. Those new Mitas Powerpull tires worked well but will receive some modifications for next year to get more performance out of them. With 3 wins at 4 Dutch Championship rounds, the team has probably raised the bar once again after all those changes on the tractor.
That gives hope for an interesting Euro Cup season 2022 in the light mod class.
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