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Spotlight on Roadsters - RocketSports


A beautiful looking car, near 200 horsepower and sticky tires – what can be better?  Plus the thrill of a single seat racing car – no roof – it’s you against the world.  You can be racing in the iRace RocketSports category.

The Chilli Rowdster is not a Historic Car, it is a new car utilising a donor ’H’ series Holden to supply the motor, running gear and front & rear ends. The body is a widened 1962 ‘replica’ Indianapolis Watson Roadster.

The jig built ‘Formula Q’ chassis is a simple combination of a series of hoops connected by two main rails extending from the original front sub frame.  The standard HQ-HZ suspension components bolt straight on and is capable of taking any type of body shape and motor.  The basic Rowdster can be built for the sole purpose of track use or built up for road use as well by using mainly standard donor car parts.

The ‘Formula Q’ Chassis:  The basic chassis is jig built, has reassuringly large box section side members, roll-bar spec tubular cross member hoops and cleverly incorporates the HQ front sub frame and double wishbones for good geometry and the rear retains the live rear axle with four link trailing arms.  Despite the modest mechanical specification, at around 800kg it weighs a lot less than a HQ so the performance is rapid with good brakes, safe handling and of course reliability.

The ‘Chilli Rowdster’ Body:  The fibreglass body shell is based on the traditional late 50’s – early 60’s Watson Indy Roadster.  It is just over 200mm wider than the original Watson Roadsters to allow a cosy second seat.

The Race Car:  The car is the standard ‘Formula Q’ chassis, ‘Chilli Rowdster’ body but with a few ‘go fast’  and safety bits added.

The motor is either a 202 or 3.3 block with race spec internals running at around 12:1 compression and triple carbs which requies avgas or 98 Octane or higher for reliability reasons.  The gearbox is either the M21 4 speed or the Celica/Supra 5 speed running back to a LSD Banjo or Salisbury rear end. The rear brakes are upgraded to late model Commodore,  with adjustable bias valve placed in the cockpit.  The wheels are either 17 or 18 inch running 8 inch on the front and 11 inch on the rear wrapped in a full slick tyres.

The motor is a standard 202 bottom, with a HQ race cam and the head has had a little work. The gas system runs the Gas Research Carby on the bigger two barrel manifold.  The gearbox is a 3 speed M20 and runs back to a standard Banjo rear end.  The wheels are commonly available 14 or 15 inch and in keeping with the sporting intention, the vehicle is fitted out with a CAMS spec Roll Bar, harness and extinguisher.  There is currently an upgrade in progress to a late model Ecotec V6 motor from a VZ Commodore which includes the 6 speed manual transmission.

If you would like to try there are cars available for lease at http://rmmotorsport.com.au/

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