MF1 Racing's managing director Colin Kolles says Toro Rosso's plans to use a V10 engine during the 2006 season should be considered illegal.
Toro Rosso, owned by Red Bull after the company took over the Minardi team last year, will use V10 engines this season while their rivals fit the new V8s.
The team were allowed to run V10s when they were Minardi, but Kolles believes now that their financial problems have been solved Toro Rosso should follow the rules and use V8s.
Kolles suggested that if Toro Rosso are in front of his own Midland team when the season starts in Bahrain, he might consider taking some action.
"The car is not legal. That is the point. It is very clear. Obviously I have a very clear opinion. This engine does not belong in Formula One any more," said Kolles during the launch of their new car.
"It is not the regulation. It has been accepted due to a financial reason for Minardi and this is not any more the case.
"For me it is not understandable - (Red Bull) spending hundreds of millions, having two Formula One teams and bullshitting the world, basically.
"If they are in front of us then they will have a problem because I will not be very happy with this and I am very clear about this."
The equivalence formula introduced by the FIA to limit V10s has left several teams unhappy, although the governing body said the formula could change quickly.
"I trust the FIA. It is in the hands of the FIA. We are looking at it, but we are looking very carefully at it," added Kolles.
MF1, racing under the Jordan name, struggled for pace last year and stand to lose the most if Toro Rosso are competitive.
Over the winter, Midland have carried out tests with both V8 and V10 engines in order to provide data to the FIA to show them the equivalence formula is not working.
Kolles, however, said further limiting the V10s will not solve the problem.
"It is not a question of making the engines slower," he said. "It is a question that the regulations state a V8 engine, and not a restricted V10 engine. It was an exception for Minardi due to financial reasons. For us it is not only a V8/V10 the power, it is also a financial matter.
"A V8 engine is much more expensive than a V10 engine and if it is restricted you can run much longer and be more reliable. It has more torque. It is not just restricting the engine, it is a completely different world.
"They are expecting to be competitive. To be honest, for me it is a shame. But okay, it is the FIA who told us that they will take care and it will not happen. So we trust the FIA that they will control it and that they will be at the back of the grid. That is it."
Portuguese driver Tiago Monteiro admitted he was worried Toro Rosso would prove more competitive than his own team.
"I am personally worried," Monteiro said. "I don't know exactly how the team feels about it, but I'm not happy. We did a big V10/V8 comparison and I was 0.7s quicker with the same car with a different engine.
"So for me, it's totally unfair that they use the V10 - at the moment [with the current restrictions] the V10 is seven-tenths quicker. So if the rules stay like that, initially Toro Rosso will definitely be quicker than us."