Production of S5000 race cars has been given the green light following a successful test day at Winton Raceway.

Series technical partner Garry Rogers Motorsport has made several modifications to the suspension, brakes and cooling systems on the V8 powered Onroak-Ligier single-seater in preparation for the inaugural S5000 season.    

Development driver Tim Macrow successfully tested the car, in its final specification, at the Victorian circuit which has given GRM the confidence to push forward with production of the single seaters.  

The team also took the opportunity to evaluate numerous tyre options from US tyre specialists Hoosier.

GRM currently has four other Onroak-Ligier tubs at its workshop, with a further nine ordered tubs set to arrive in late May or early June.

“This is GRM’s first outing with the S5000 after the hand-over day back in December. Up to that point, Michael Borland had done  tremendous job getting to a particular level,” said GRM director Barry Rogers.

“We spent quite some time talking with Tim (Macrow) and the guys at Borland Engineering, really working with their feedback – a lot of it was suspension and steering related, to enable use of a more logical and suitable braking system.

“We’ve done a considerable amount of work in the first quarter of this year redesigning and making the new parts. Tim has validated them now and has said that he has a lot better feel in the car.

“Our plan from here is to head back to work and start mass producing these parts to start putting 14 cars together.

“At GRM, we have a fair line-up of drivers, but we were really keen to continuing having Tim Macrow as a big part of this program. He has a lot of experience in open wheel cars and the feedback he gives the engineers in vital.

“Some guys can get in these cars and drive fantastic, but can’t give the feedback. Tim is a real professional so it’s great to have him as this program develops along.”

Macrow admitted the changes have made a big difference to the car compared to its original form which was unveiled late last year.

“We have evaluated the suspension changes that the boys at GRM have made. We’ve got new uprights and different suspension arms, so we’ve been testing that, along with some new tyres from Hoosier,” said Macrow.

“The feeling with the car is absolutely brilliant. It has made a big difference to how it handles. Now all we’re doing is some suspension tuning work, changing a few springs and just trying to get the car balanced.

“By the end of the day, we’ll have a good direction on where we are going and we’ll be sorted for the next test days.”

The S5000 car is set to conduct demo laps at Sydney Motorsport Park from May 17-19 ahead of its inaugural round at Sandown from September 20-22.