Magazines:  Real Estate Shopping: Adult Costumes  |  Kids Costumes  |  Car Books  |  Guitars |  Electronics
This Issue Archived Articles Blog About Us Contact Us

Speed Racer

Here it is - Australia's best modified Mini! An imported and chopped Sprint, plump with a twincam injected motor, straight cut gears, Quaife LSD, 6 pot calipers and a rippling muscular body!

Words by Michael Knowling, Photos by Julian Edgar

Click on pics to view larger images

Click for larger image

Craig Williams has been throwing bricks around since he was a teenager. And no, it wasn't because he was a hoodlum with a habit of breaking and entering; rather he loved driving what is arguably Austin's finest creation - the sensational Mini. And that love has never lost its sparkle. Over the course of the next twenty or so years, he focussed on building up a concourse winning Cooper S, a hillclimb Mini and even a motorkhana Moke. But he rested only when he owned the ultimate Mini - the Sprint version. This little terrier got everything the famous Cooper S received in its Christmas stocking - plus a thorough axe job on the body. Its overall height is a full four inches lower than a usual Mini, which is more than enough to make the Mini even more mini inside! The original idea of cutting down the body profile was to reduce the car's frontal area - thus enabling it to slide though the air more efficiently. It was a change that was reputedly good for up to 20 mph of extra top speed with no additional power required - so it was a big success!

Click for larger image

Now, the difficult part for Craig was that the Sprint was built only in the UK. So he had to leave his home in Australia and fly to England in order to inspect a few of these raries. Unfortunately, he didn't end up finding the exact car he was chasing, and came away leaving only a description of what he wanted with Mini specialist, Speedwell. A full two Sprint-less years later, Craig received an international beep-beep-beep call from Speedwell to tell him they'd tracked down a genuine one-owner 1963 Sprint. And by all descriptions, it fitted Craig's bill perfectly. Without even travelling to inspect the distant vehicle, he put word to Speedwell to make it his and set about treating it to a full ground-up restoration.

Click for larger image

But during this two year interlude an idea had formed between Craig's ears - an extravagant idea. This Sprint wasn't going to wind up as merely a restored show pony; it was to be a super-serious Targa racecar/occasional street car. So to satisfy Craig's request to push the envelope further, Speedwell seam-welded the body for maximum rigidity and installed an FIA-approved full chrome-moly roll cage. Extending from the front to rear shock towers, the cage contained within this Mini really increases its crash safety and chassis stiffness no end. It's about as flexible as a police officer that's just pulled you over for doing 100 km/h in a 60 zone!

The bulk of the motor and driveline assembly was also a product of English engineering. Craig began on this topic by stating "you can take the swept capacity higher than this one, but you get much less reliabilty in return". So for safety's sake, the generic A-series block was reamed out to "only" 1380cc using a billet steel crankshaft and 73.5mm Cossie forged pistons. For added bottom-end durability, a beautiful set of Richard Longman billet aluminium rods was also included in the build. (BTW, I bet that guy - Richard Longman - copped it at school about his name!)

Click for larger image

But the real jewel in the car's crown is its cylinder head and induction system. Gone is the original simple 2 valve pushrod head and in its place is a $10k-plus KAD DOHC 16 valve alloy head. This highly desirable piece of engineering is an aftermarket kit that's been developed in-house at KAD, and it's since proven very successful in motorsport around the UK. With such dramatically improved head flows, Craig could then afford to opt for a set of fairly mild spec KAD cams to keep a good spread of torque and optimum drivability. An extremely important factor when you need to be able to punch the car out of tight corners.

The bit that didn't stay on the car very long after it arrived in Oz was the traditional induction setup comprising twin 40mm Weber carbs. Sydney's Injection Perfection improved matters with their wonderful quad throttle body induction system (which bolted straight onto the existing Weber manifold), and took care of the fuel and ignition management side of things with a Microtech Digi 2 programmable ECU. This is configured with direct fire ignition and multipoint injector firing to deliver far superior torque and throttle response than the previous twin carbies were able to provide.

Click for larger image

The KAD-assembled 1380cc four now makes available a solid peak power of 135hp at 7300 rpm - but given a few more revs, Craig's confident it'll pull more ponies. Not that that's what he wants to do, though. In a Targa racing environment, it isn't worth sacrificing the engine's reliability or trading off any of its terrific response at all revs. Running across the front axle line is a KAD 5-speed non-synchro dog box that allows supremely fast gear changes along those tight Targa roads, and it's mated to a 3.6:1 Quaife LSD centre to give the FWD chassis maximum traction. A completely standard set of Mini Cooper S driveshafts were slid into the heart of the 'box back in England and have proven totally reliable ever since.

Click for larger image

More European good bits have gone into the suspension - and brakes as well. At the front end resides a pair of Spax adjustable coil-overs, combined with adjustable lower arms to alter the alignment. Outward of this, KAD six-pot calipers biting 9? inch vented discs ensure this 650kg rocket pulls up in time for every corner with bags of stopping power to spare. A couple of paces back towards the rear and there's alloy KAD trailing arms designed to reduce the sprung mass of the suspension assembly, and an adjustable camber bracket to stand the wheels up at the right angle. Finned alloy drums take care of retardation duties for the back end, and despite a major contrast with the front brakes, still perform remarkably well. And when Craig needs to get the back end of the car around an extra-tight corner, he can always yank on the hydraulic handbrake for a rush of adrenaline!

Click for larger image

Out in the elements of full-blown competition, Craig says the Sprint is a bit oversteery in its current configuration, and he need to tune the rear suspension more to keep it tied down. There isn't much weight over the rear wheels either, since most of that 650kg kerb mass is over the front. Oh, and putting 135 horses through the front tyres of a car of the Sprint's vintage also results in some torque steer to fight against! Despite owning/managing Jazz Alloy Wheels Aust, Craig managed to steer away from fitting a current style set of rims and opted for the retro-styling of a set of 13x6 Miniators. A good move for our money - they suit the era of the car perfectly. Worn on the Minators are 175/50 Pirelli P5000 Dragos that stick like you-know-what.

The contemporary theme of the car has been upheld in selecting the red and black factory colour scheme and applying it over what is essentially a standard Sprint body - minus its front and rear body seams. By far this most noticeable panel re-working has been on that big-nose bonnet, which was required to clear the KAD cylinder head. Fabricated by a professional coachbuilder in England, it's even detailed down to the centre ridge that runs along the length of the bonnet! Other additions include a set of four Group 5 wheel arch flares, leather bonnet straps and some minimalist external mirrors. Standard features of the Sprint are the slide-back front windows.

Click for larger image

"Race" is the theme of the interior, with the afore-mentioned cage, custom (narrowed) Velo Race seats, OMP harnesses and a fire extinguisher. Add to this a Terratrip rally computer, intercom (it's damn loud inside!), Smiths 10,000 rpm tacho, SWM wheel and knob and a helmet net hung from the centre cross-bar of the cage. It's a neat but no-frills workplace for Craig.

Click for larger image
Since its completion back in 1996, the car has so far competed in three Targa Tasmania events and has taken class victories in two of those, with a bonus accolade of winning the Best Presented trophy. Not bad considering there were over 200 other entrants! See, the Mini can still perform amongst today's breed of performance cars!


Jazz Alloy Wheels Aust.
1800 225 299

Injection Perfection
+61 2 9791 3122

Velo Racing Seats
+61 8 8369 0488

Did you enjoy this article?

Please consider supporting AutoSpeed with a small contribution. More Info...

Share this Article: 

More of our most popular articles.
A brilliant new temperature controller that's so cheap it's unbelievable.

DIY Tech Features - 15 November, 2011

$25 Temperature Controller and Display!

Why turbo engines give better fuel economy

Technical Features - 13 February, 2008

Turbo'd For Fuel Economy

Under $10 for a remote-controlled immobiliser!

DIY Tech Features - 27 November, 2012

DIY classic car immobiliser

The beautiful 1950s Mercedes 300SL

Special Features - 27 February, 2008

The Gull-Wind Marvel

Aluminium bellmouths in minutes

DIY Tech Features - 10 December, 2013

Making your own Bellmouths

Designing a DIY electric bike

DIY Tech Features - 4 February, 2005

Building an Electric Bike Part 1

Assessing the performance of an amazing human powered vehicle

DIY Tech Features - 15 January, 2008

Air 150 Recumbent Trike, Part 2

Squirt your intercooler spray for 5, 10 or 20 seconds - all at the press of a single button!

DIY Tech Features - 2 September, 2008

Intercooler Spray Squirter

DIY building of very light vehicles from steel tube

DIY Tech Features - 17 March, 2009

Building Ultra Light-Weight Tubular Frame Vehicles, Part 1

The correct ignition timing settings

Technical Features - 21 September, 2007

Getting the Ignition Timing Right

Copyright © 1996-2018 Web Publications Pty Limited. All Rights ReservedRSS|Privacy policy|Advertise
Consulting Services: Magento Experts|Technologies : Magento Extensions|ReadytoShip