Eight-second Monaro blows intake manifold making 1200rwhp on the dyno – Video

Chris McDonald's eight-second twin-turbo small-block powered Holden Monaro on the dyno at MotorEx


THE guys at McDonald Brothers Racing have a long history in the Australian drag racing scene and their workshop in Thomastown, Melbourne does some pretty incredible chassis work. From four link kits for just about any car you like through to full custom rails and independent front suspension systems they do it all and the cool thing is they can fit it themselves at their factory or ship it out for other businesses and DIYers.

Over the last twelve months or so Chris McDonald has been getting back into the racing scene with a street-based car rather than the dragsters he previously piloted. Chris’s 2004 Holden Monaro has been a development car for the business and has all the goodies from the McDonald Brothers four link and nine-inch rear end to the custom tubular front end.

 Under the bonnet is a 383ci small-block Chev – not an LS – boosted by twin Garrett GT3584 turbos. The car previously ran a big single 106mm turbo and the switch to twins has seen power gains of around 200hp despite running the same boost. Thus far the car has gone 8.3 @ 171mph down the quarter with a couple of pedals and Chris is confident it’ll go sevens – they haven’t even started to lean on it yet.

Chris had the car at Meguiar’s MotorEx over the weekend where he gave the car a run on the Mainline hub dyno. Adam Rogash from MPW was running the dyno for the weekend and he is also Chris’s tuner so they turned up the boost with the aim of making over 1000rwhp. On Adam’s chassis dyno it previously made 970rwhp.

With 26psi dialled up on the Haltech ECU the Monaro spat out 1217rwhp before it split a weld on the sheet metal intake manifold! Fortunately Chris has a new Plazmaman one on the way but in the meantime he’ll patch it up and keep chasing that seven.