Nissan Aero Working Better

Todd Kelly has given the revised aerodynamic set-up of the Nissan Altima V8 Supercar a cautious thumbs up after he posted second fastest time in the sydney.com test day at Sydney Motorsport Park last Saturday.

And not only was Todd second fastest, but brother and Jack Daniel’s teammate Rick Kelly finished third fastest, while the two Norton Altimas of Michael Caruso and James Moffat also finished in the top 10.

In 2013 Nissan Motorsport team became convinced the aerodynamic set-up of the Altima was inefficient at speeds above 220km/h and was given the okay by V8 Supercars to submit revisions for homologation over the summer.

“As far as the aero goes, the only guy who has been around other cars today (on the SMP main straight) is Caruso and I think we are still dropping back a little bit from the cars in front. But it doesn’t seem to be as bad as what it was,” Kelly told v8supercars.com.au. “So I think we have made a good gain.

“Importantly, the cars still feel balanced in the corners despite re-doing the cars. We haven’t messed up or shifted the front-to-rear balance.”

The revised aero was developed by Nissan Motorsport here and Nismo suppliers in the England using computational fluid dynamics (CFD) and then physically approved when the new Volvo S80’s aero kit was signed off. 

“We have slightly moved the undertray, pulled the lower cheeks out and pulled the upper cheeks in at the front, moved the rear wing up and back and slightly modified the side skirts,” Kelly explained. 

“All the things we did on the front and back of the car were to achieve the downforce homologation figures while reducing the amount of drag.”

The other aspect of the Nissan’s technical package that caused concern last year was the Nissan VK56DE engine, but significant improvements are unlikely to flow in for that until mid-year.

An example of the Nissan 5.0-litre race engine along with one of Kelly Racing’s old Chevrolet push-rod units from its Holden days has been at Nismo in Japan since November. 

“Nismo has done a fair bit of dynoing and simulation and they have got a lot of stuff they have designed and have got in production to test. And once they test it and it’s a gain, we have to go flat out to get it into the car.”

Revised production cylinder heads with thicker walls are also being cast in the USA.

“Where we went with our ports at the end of last year we started to have some cracking of our cylinder heads and a few failures so we have come back a little in port size from there to get our reliability back,” Kelly explained. “We have planned and allowed to be on that spec level for at least six months. 

“But I am hoping the big chunk (performance gain) is in the aero.”

The focus on the aerodynamic issue has meant other areas of development have been held in abeyance over summer. However, the Altima did display strong chassis performance all year and if the new aero kit works properly Kelly is expecting consistently better performances from all four cars when the V8 Supercars Championship kicks off at the Clipsal 500 on February 27 to March 2. 

“We know the engine is not the best out there, but with the package we have now we think it is good enough for us to be aiming for the top 10 every where we go,” he said.