Todd Kelly has changed race engineers for one last time this season as Nissan Motorsport searches for a full-time solution for 2017.

The veteran’s year was dealt a significant blow in May when long-time staff member Jesse Walker left the squad for a new role in the United States.

Nissan Motorsport’s engineering manager Perry Kapper was temporarily placed into the role before the arrival of ex-Roush Fenway NASCAR man Matt Rumfield.

That experiment lasted just a handful of events before Blake Smith, who had engineered Garth Tander before splitting with the Holden Racing Team mid-season, was recruited on a fill-in basis.

Smith missed Pukekohe due to a prior commitment but returns to the car for this weekend’s Coates Hire Sydney 500.

Kelly sits 14th in the championship heading to Sydney, which is three places higher than he has finished in any season since Kelly Racing started in 2009.

The 37-year-old is convinced that his year could have been significantly better if he’d had a stable engineering partner through the season.

“The fact that I haven’t had a full time engineer has been my biggest issue this year,” Kelly told Speedcafe.com.

“To have had this many changes during a season in a category this competitive is an absolute nightmare.

“Different theories, different ideas on set-up and no time to build any momentum or relationship (has hurt).

“If you do that to any driver it’d unsettle them, it doesn’t matter who you are.

“It’s great that Pez (Kapper) has been able to jump in and fill the hole at times, but it’s been a big challenge.

“We’d love to do something with Blake full-time next year, but it’s difficult with him being based in Sydney.

“What I need is someone who is full-time, on the ground and focussed on getting us further up the grid.

“We’re working through our options and will see what we can do for 2017.”

Rick Kelly’s engineer, Queensland-based George Commins, already works remotely between race meetings.

The 2006 Supercars championship winning driver sits 13th in the standings, just 42 points clear of Todd.

Rick has finished ahead of his brother in the championship every year since 2005.

Todd finished today’s practice as the leading Nissan runner in ninth ahead of Rick Kelly (14th), Dale Wood (17th) and Michael Caruso, who was just 22nd after an early crash.