At the end of October the FIA released a new appendix to the sporting regulations covering the detail of the engine freeze regulations.
This was the team's first sight of what they will be allowed to do before the engines are fully homologated.
The new rules allow the teams some freedom to change the detail of the engine once, before the final homologation stage, in the process.
These changes are to allow the other new rule imposing a strict 19,000rpm limit. The concept of an engine freeze is not favoured by the engine manufacturers, but another oddity in the rules may also frustrate fans that will potentially see less overtaking.
The first step in the process was when sample engines were taken back in Monaco, in expectation of the initial freeze rules under the so called Monaco Agreement.
Thereafter, engines had to be submitted by the Japanese GP, although dispensation was given for motors which had yet to complete two race distances. These engines could be submitted after the Brazilian GP.
The teams now have until December 15th to make any planned changes to certain areas of the engine. These changes are restricted to the top end - pistons, con rods, cams and valves - and are largely to accommodate the retuning of the engine down to the 19,000rpm limit.
The other changes permissible are the detail of the engine mounting and ancillary installation. These cannot provide a performance benefit, but will allow the team to tailor the plumbing around the engine to suit the new chassis.
After this date, the engines are frozen and no changes can be made without dispensation from the FIA. The only changes that can be made are mainly to resolve specific reliability problems.
The new rev limit will be enforced by the teams' own ECUs, thus there now remains no potential to over rev the engine.
As teams have been running well over this limit throughout 2006, they will have no reliability problems in running the engines right up to the lower limit throughout a race weekend.
This presents a problem, as currently the driver could alter the engine's settings to allow a boost of power for overtaking. This artificial 'push-to-pass' solution will now be gone, so any drivers wanting to pass will have to do so with no other advantage.
Added to the fact that there will be a single tyre supplier, there will be even less scope for overtaking than before.
This is clearly at odds with one of the FIA's stated aims of improving the show.