AFTER six hours of practice across the previous three days, the field is ready to rumble for the 2023 Repco Bathurst 1000.
There were so many unknowns surrounding the first ever Gen3 Great Race, but plenty has become at least a little clearer.
V8 Sleuth explores the factors that will decide the race and what we’ve learned so far…
The form
The #99 Erebus Motorsport Camaro of Brodie Kostecki/David Russell has been the pacesetter for the bulk of the week, culminating in Kostecki’s stunning lap in the Top 10 Shootout, where he recovered from a mistake at Hell Corner to take pole.
Erebus’ sister entry of Will Brown/Jack Perkins will start just 17th after a crash for Brown in qualifying, but cannot be discounted.
Elsewhere, Triple Eight’s Broc Feeney/Jamie Whincup and Shane van Gisbergen/Richie Stanaway pairings appeared to have a slow start to their campaign before coming to the fore on Saturday.
The fastest Fords don’t have the outright pace of the Camaros, but six Mustangs did qualify inside the top 10. That included both Grove Racing cars of David Reynolds/Garth Tander and Matt Payne/Kevin Estre. Tickford’s Cam Waters/James Moffat start as the lead Ford in third.
MORE: Waters’ two-word plan for Bathurst 1000
One-lap speed and race pace could be two very different things, though.
While Kostecki pumped out a 2:04.2719s in the Shootout, increased levels of tyre degradation with the low-downforce Gen3 cars and Soft compound tyres should mean lap times are nowhere near that for much of the race.
Some insight into race pace could be garnered from Andre Heimgartner’s 15-lap run during Practice 6, with the Brad Jones Racing ace clocking mid-to-high 2:08s without fail throughout (excluding outlap and inlap).
So that’s a ballpark figure for the kind of number drivers might target, allowing them to hold a consistent pace. How fast they push will relate directly to…
Strategy
High tyre degradation overlayed against longer fuel windows – and the removal of a minimum number of Compulsory Pit Stops – leaves the strategy options wide open.
The longest stint completed during practice was Grove Racing co-driver Kevin Estre’s 25-lap run yesterday. It’s believed the maximum fuel range is in the vicinity of 31 laps.
As Triple Eight technical director Jeromy Moore explained to V8 Sleuth ahead of the weekend: “What the tyres will do over a full stint is a big question.
“You could probably do five stops to go to the end on fuel, but it really depends on tyre deg, how they hold up, if that’s going to be the quickest way or not.
“Anything between six, seven, eight, it could be the same number of stops like last year because of the tyres limiting the strategy, not the fuel.
“You could have so diverse strategies going through the race, I think it’s one of the strengths now of having this high fuel capacity car and running a degrading tyre.
“There’s so much of a window of strategy, now that you don’t have to do seven.
“Sandown it didn’t play out much, but who knows with this race, there could be some oddball strategies out there.”
Double-stacking
Another factor to keep an eye on is how teams try to manage avoiding double-stacking, which Moore explains will be an even bigger factor than previously.
“It’s going to be a double-stack risk the whole race,” he says.
“If you go the full tank trying to do five stops, not coming in under the Safety Cars, then you’ve got less risk. If you want to do more stops and not fill it up each time, you’ll be at the risk of double-stacking.
“I think you’ll see a lot of that happening if there’s a Safety Car in that scenario.
“The fuel flow rate being so low, fuel capacity being so high, it means you get a big gain if you’re coming in for a splash under SC, because it could be a 20 second dump you put in there and you’ll want to do an extra stop because of that.
“It’s going to be interesting up and down pitlane, are people coming in, are they not? It’s going to be quite a different race to what we normally see, everyone has converged to the same strategies over the last few years, but now, who knows.”
Tuning the car
Drivers no longer have in-car adjustable anti-roll bars to tune the balance of their cars across a stint under Gen3. That will make adjustments in pitstops even more important.
“With the slow flow rate, you have a bit of time to change the car,” explains Moore.
“The roll-bars you can adjust in the wheel arch, you can adjust ride heights, droop settings, rear wing angle, you can do quite a bit on the car during the race, moreso than before because of the fuel time.”
Brake changes
Brake changes continue to look problematic, with Tickford, Grove Racing and Dick Johnson Racing coming unstuck while practicing the procedure.
Unlike the Sandown 500, there is a mandatory brake pad change at Bathurst, to be completed between laps 55 and 120.
“We have to change brake pads, but we’re allowed to do discs, so teams might be doing discs, calipers and pads all at once,” says Moore.
“It’s a shame, because we set out the target (when designing Gen3) of not having to change brakes here, but we’ve had some taper issues, so it’s erring on the side of caution to allowing it.
“You can’t force teams not to do it and they have a brake issue, so I completely understand on the Supercars side of things.
“Hopefully we’ll learn from this and some small tweaks to the cooling, we can get away with not having to change brakes, which will be good in terms of the safety side of things.”
Reliability
Reliability was sound at the Sandown 500, besides Garth Tander’s loose wheel and a shredded serpentine belt for the Castrol Mustang of Thomas Randle/Garry Jacobson.
There have been a couple of issues pop up across Bathurst practice, including some clutch woes for Cameron Hill/Jaylyn Robotham and another shredded serpentine belt for another Tickford Mustang (this time James Courtney/Zak Best).
That led Tickford CEO Tim Edwards to voice concern over debris pick-up.
Engines have seemed reliable thus far in Gen3, but as for all parts, this will be their sternest test yet, across 1000km.
Moore downplays the reliability concerns, particularly around the much-maligned Gen3 steering racks.
“Engine-wise they’ve been (largely) bullet-proof through the year,” he says.
“The gearbox is the same as we’ve been running, the suspension, we’ve had pretty much zero failures there. We’ve done a tune-up to the wheel nuts (between Sandown and Bathurst) and are pretty confident that won’t be an issue.
“I’m confident we’ll have good reliability and it’s something that hasn’t been spoken enough about.
“We rolled out 25 cars in Newcastle, everything pretty much brand new, and had a wheel bearing failure because it was a Chinese-spec wheel bearing on the Walkinshaw car, and smashing kerbs, the majority of cars got through, it was a good story. Same with Sandown.
“There’s been a lot of work on the steering racks, but that’s more around feedback to the driver than reliability.
“We’ve never had a mechanical failure of our steering racks (at Triple Eight), where it’s not working anymore. It’s always been ‘I don’t like the feel’ or ‘it’s not giving me good feedback’. That’s what we’ve been working with Supercars on for 2024.”
Other factors to watch
On-track, tyre marble build-up is set to present an increasing challenge as the day goes on, as Tickford Racing’s Thomas Randle explains.
“I think another thing you have got to consider is the amount of marbles that are going to be off-line, especially on a soft tyre,” Randle told V8 Sleuth. “We saw at Sandown how bad it was off-line and that was half the distance of here.
“So trying to stay focused, especially the last couple of stints when it’s just going to be one line everywhere and if you just miss that you’ll be in all of the marbles, so it’s certainly going to be another thing to have in the back of your head.”
And then of course, there are the weather gods.
Per the Bureau of Meteorology, there is a zero percent chance of rain today in Bathurst… but the Mountain is notoriously unpredictable.
