Team 18 is one of five teams with KRE engines
With an engine optimization, five Holden teams will soon be back on the level of their Supercars rivals.
Dyno tests after the 2020 season end at Bathurst 1000 showed that teams with KRE engines had only slightly less power compared to Ford teams and the two teams with Walkinshaw engines (Walkinshaw Andretti United and Erebus Motorsport).
KRE engines are included in the ZB Commodores, used by Brad Jones Racing, Matt Stone Racing, Team 18, Team Sydney, and Triple Eight Race Engineering, which represent half of the 24-car grid.
Tests showed a deficit of four to five horsepower.
This is remedied by changing the KRE luffing ratio from 1.60 to 1.65.
Updated parts were ordered from the US and will be made available to all five teams at the same time, either in time for the Winton SuperSprint May 29-30 or the Merlin Darwin Triple Crown June 19-20.
“I think it was last year when we switched back to a 1.60 seesaw for cost reasons and when we changed rockers [piston] Rings, we obviously had a lot of drama with the rings, ”explained Ken McNamara from KRE.
“So they changed it, and then I think when they tested all the engines after Bathurst last year – Shane’s [van Gisbergen], Walkinshaw is with [Chaz] Mostert and [Cameron] Waters’ – we were four or five horsepower less or so.
“With COVID and other stuff, we hadn’t tested much when we changed the rocker arm ratio, and it looks like you’re making a change across the board with our special cylinder head, and it obviously affects every engine differently, and obviously we were a little less so.
“The Ford and Walkinshaw have a different type of rocker arm, so the relationship with the rocker arm geometry is a little different.
“It’s more about making sure they’re as close on paper as possible.
“Was it shown on the racetrack at Bathurst? Not really.
“I mean, you might see a thousandth in the microsector or a hundredth in the straight, but it didn’t seem to affect Shane and Waters and all of these guys who race.
“Our stock wasn’t in that rocker anymore anyway, so we figured we’d test it and everyone was happy and we ordered the 1.65 which will be for Winton or Darwin whenever they come up.”
Darwin will be a more performance-dependent circuit than Winton due to the length of its main straights.
The five teams have the opportunity to change the seesaws.
KRE teams will use the existing 1.60 rockers at the Beaurepaires Tasmania SuperSprint this weekend.
