The three IZOD IndyCar Series engine suppliers - Honda, Chevrolet and Lotus - report that they are happy with their progress toward the 2012 season and with their work developing the new Dallara DW12 IndyCar Safety Cell chassis that all teams will be using from March.

There had been concerns among the teams and the engine manufacturers during early testing in November that the new car was under-performing on ovals in particular, and was suffering from too much aerodynamic drag and problematic weight distribution resulting in speeds 10-15mph slower than expected on high speed circuits.

Insiders said at the time that Dallara's CFD (computational fluid dynamics) modelling for the new car might have been "a bit too rudimentary" and that Dallara had "out-smarted themselves" by making the car too rear-heavy with the result that it has a tendency to want to spin (oversteer) going into a high speed turn and then suddenly wanting to swing the car out of the turn (understeer) toward the wall on the turn exit - a clearly dangerous characteristic.

"[It's not] going as fast as we wanted or expected and we're trying to identify why the theoretical world doesn't match real world at the race track," IndyCar's Vice-President of Technology Will Phillips admitted to SPEED TV channel last month. "At very high speeds, we have disparity in the data."

But after test programs by Honda and Chevrolet on three ovals and road/street circuits covering a total of over 5500 miles, all parties appear happier with the car following the introduction of lightened gearbox parts at the rear and the addition of more weight at the front to address the balance issues on ovals. Teams were particularly buoyed by news that Dallara has now committed to producing and suppling new suspension components intended to tackle the remaining problems at their own expense.

"As requested by IndyCar, Dallara will design an alternative set of suspensions to move back 2 inches the front wheels and 1 inch the rear wheels," confirmed the company's head of research and development Andrea Toso. "Both front and both rear suspensions will be available for the teams from the catalogue and can be utilised in any combination front to rear at all the events. Teams will take delivery of their cars with the current set of suspensions and, should they decide to start the season with the alternative set, they can get free of charge replacement based on the return of the current set."

Dallara will also conduct wind tunnel tests early in January to investigate the aerodynamic drag issues, which may lead to them producing an all-new oval aero kit for the car on ovals.

Honda and Chevrolet are certainly encouraged by the performance of their respective new specification 2.2-litre, turbocharged V6 engines as well as the standardised McLaren ECU that was the focus of the most recent week's testing at Sebring International Raceway with Takuma Sato (for Honda) and Tony Kanaan (for Chevrolet).

Meanwhile Lotus have confirmed that their engine's first on-track outing will be on January 13-14 at Palm Beach International Raceway with Simona de Silvestro at the wheel of #78 HVM car.

"Palm Beach will be more of an engine shakedown test. We're not really concerned about how many miles we run," said HVM Racing manager Vince Kremer, who added that the real testing will come in February at Sebring International Raceway. "Sebring will be getting more into developing the engine on the track," he confirmed.

"[The schedule] is quite ambitious, and that's just the on-track," he admitted. "We haven't talked about any off-track testing, seven-post shaker rig testing or twisting the chassis. The good thing is we're working as a co-operative group with Dreyer & Reinbold and Bryan Herta [Autosport] and we seem to be working quite well together."

Although one of the stable of Lotus-powered teams in 2012, HVM's livery will remain substantially unaltered from 2011 and stick to the colours of main sponsors Nuclear Clean Energy and Entergy while other Lotus-aligned teams will predominantly switch to the manufacturer's colours, in line with Lotus' strategy in other motor sports series.

"We may go to a little darker green and have a yellow stripe," Kremer said. "Lotus has been very good about working it out with us. The recognition will still be there."

15 teams received their orders of the new Dallara chassis on December 15, with a further 15 expected to be be complete on January 15. Dallara is expected to deliver 60 chassis in total - costing $385,000 apiece - via their Indianapolis facility before the start of the season on March 25.