Hennie Groenewald dominated Round 4 of the 2012 Bridgestone Production Car championship at the Zwartkops Raceway at the weekend to further extend his championship points lead to 16.He also set a circuit lap record.The championship leader's Subaru WRX STI started two races from pole, won three times and set three fastest laps but team principal Carel Pienaar cautioned that they were lucky. “We know other teams were quicker than us in practice," he said, "but they didn’t convert their pace into race performance whereas we had a strategy that worked perfectly. Hennie was on top form but the cars he passed in Race 2 were more as a result of other driver’s errors than out-and-out pace."Richard Pinard claimed his best qualifying performance of the season so far, planting his Subaru WRX STI sixth on the grid, but his bout of poor luck continued in Pretoria.PRACTICE AND QUALIFYING:Groenewald set the second-quickest time in P1, fastest in P2 and was third in P3. During the qualifying round he set a time of 1min04:741, nearly half a second faster than Michael Stephen’s works Audi.Groenewald said: "I was surprised by my time, which is the first under 1min05 for the car. I knew we had a competitive car after practice but Michael set a better time than me on fresh rubber so I was quite surprised by my time as it is the same car we had in Port Elizabeth and Cape Town."The cooler air and higher altitude suits the Subaru."RACE 1Groenewald put in a blistering lap to open a sizeable lead ahead of his rivals. "I did a flat-out lap to build a lead as our pace drops off towards the end of the race while the Audis get stronger.”Pinard was locked in a fierce battle with Audi's Johan Fourie for seventh place.RACE 2The top six finishers were inverted, leaving Groenewald sixth on the grid. Half way around the first lap he was up to fifth, then third on lap two, second on lap three and challenged BMW's Anthony Taylor’ for the lead on lap 4. Groenewald said: “Anthony put a wheel on to the dirt and as he lifted I put the car’s nose in the gap and went for it. I was in the right place at the right time during the race and maximized them to my advantage.”Team boss Carel added: “Hennie is a master of clean overtaking; there isn’t a single mark on the car. We gambled on using new tyres for Race 2 to set the fastest lap which would give us pole for Race 3 and our plan worked perfectly”.Pinard's car suffered brake issues and hoped the team could find a cure on the last lap to set a time for race 3. RACE 3Groenewald led the field in the final race, which started at dusk. As the warring German marques tripped over each other, Groenewald opened a massive lead to finish the double points race three seconds ahead of the pack.Pinard was forced to retire as his brake issues reappeared. “I’m naturally very disappointed but at the same time, I’m ecstatic for the team."The next round of the Production Car Championship is in Durban as part of the Top Gear festival on June 16 - 17.