No off-throttle blowing allowed in 2012 as teams block bid to allow the practice

A move to ban blown diffusers in 2012 through the mandatory use of periscope exhausts had not been enough to quell fears that some outfits could still try and make use of hot gases to help boost the aerodynamic performance of their cars - perhaps by blowing air over suspension components or wings.

Those suspicions resulted in the FIA issuing a technical directive last month informing teams that there will be severe limitations on engine mapping next year to minimise the possibilities of off-throttle blowing.

The timing of that decision left several teams unhappy, because they had already begun designing their 2012 cars assuming that blowing could still be implemented - a practice that uses up fuel so would require a larger fuel tank.

McLaren team principal Martin Whitmarsh said in India: "The clarification is a bit late and a few people wasted a bit of time, money and effort, but that is the same for all of us. We will look forward now."

Outside of that move, teams were pushing for the 2012 regulations to allow off-throttle blowing - with sources suggesting that unanimous approval was reached among them for this prior to their submission to the Formula 1 Commission last week for ratification.

However, the rules were rejected by the F1 Commission - with Ferrari, Sauber and HRT all deciding to vote against the regulations as they stood and forcing them back to think tank the Technical Working Group for amendment.

The TWG met in Abu Dhabi to discuss the exhaust regulations again and, although agreeing on most of the elements, a clause that would have allowed off-throttle blowing was again rejected by Ferrari, Sauber and HRT, so has been ditched for now.

Sources have revealed that the rule would have allowed any blowing of exhausts that interferes with the aerodynamic of the cars to be deemed as 'incidental' so therefore not illegal.

It is understood, however, that the TWG has agreed to re-look at the blowing rules for 2013.

With the practice effectively outlawed, the situation means that any team that uses off-throttle blowing next season will be in breach of Article 3.15 of the Formula 1 Technical Regulations - which states any part of the car that uses 'driver movement as a means of altering the aerodynamic characteristics of the car is prohibited.'

With the FIA having clarified its position on this matter, it means there is the possibility of a team protesting any rival that runs off-throttle blowing next year - as HRT pondered doing this year when the issue first came up.

The exhaust blowing saga has upset several teams, because they have already committed to elements of their 2012 design based around the idea that they would off-throttle blowing - so now their fuel tanks could be too big.

Renault boss Eric Boullier said at the Indian GP: "You have to take a decision now on car concepts and it is already too late.

"Some teams like ours have already started producing concepts of the car, so the concept has been finalised weeks ago. We need to stop changing the regulations all the time."