With the inaugural season of Gen3 Supercars having passed its halfway point, teams are now starting to send engines for partial rebuilds, as Brad Jones explains.

The NTI Townsville 500 was the sixth event of 12 this year and, as expected, the first Gen3 engines are now on their way back to their suppliers for maintenance work.

In the case of Brad Jones Racing, that is to KRE Race Engines in the South East Queensland suburb of Redland Bay, for a rebuild of the top end of their Chevrolet units.

See below for video

“Currently we’ve done between 4000 and 5000 kays – we’re midway through the season – so we’ve pulled these engines out,” says the Brad Jones Racing owner in the teams’ latest tech video.

“So, this one will just be cleaned and then we’ll put it in a box, and you can see the one over there that’s going to be replacing this one.

“It’ll go back to KRE, they’ll pull the heads off it, they’ll look at the top end, leave the bottom end in it – it’s meant to do 8000 to 10,000 kays – put new valve springs in it, check out that everything’s alright, and send it back to us.”

Engines have not been entirely trouble-free on the Chevrolet front, although reliability of powerplants has in fact been one of the success stories of Gen3 thus far, with the only significant failure ultimately caused by a gear tower breakage in a PremiAir Racing Camaro.

“There’s been a couple of engines that have had valve problems at this point in the rebuild, so it’s just something we need to stay on top of,” added Jones.

“The rebuild is scheduled, so everything’s pretty much standard here.”

In BJR’s latest tech video, Jones also explains what is different about the flywheels from the old 5.0-litre Chevrolet engines to the present-day 5.7-litre units, as well as how they are stored now.

Meanwhile, motors are again a talking point on the Ford side, with homologation team Dick Johnson Racing understood to have conducted testing earlier this week at Queensland Raceway with a view to changing the throttle body specification.

While described by some as parity testing, and certainly related to that matter, the activity was not strictly parity work given it was not part of the recently completed review process, but rather undertaken with a view to changing the Engine Specification Document.

READ MORE: Darwin fire interrupts Waters’ Bathurst engine plan

VIDEO: Mid-season engine rebuilds explained