Engine Building

Swiftune has specialised in developing and building competition A Series engines and transmissions for 50 years with great success

We can do all this …

Rebuild your existing Swiftune competition engine, meeting the needs of  the ‘next race’ deadline.
Swiftune can evaluate your non-Swiftune engine if you are dogged by poor reliability or performance.
Build new competition engines and transmissions with components selected to meet your requirements.

Rebuild Service

Engine and Transmission

Keeping race engines at the peak of their performance means regular rebuilds and Swiftune will always ensure you get ‘out’ for your next race whatever it takes. Every rebuilt engine goes on the dyno for running-in and final tuning so you will take to the grid knowing your engine is truly as good as new

New Build

Competition engines and transmissions

When only winning is good enough, racers beat a path to Swiftune’s door for a brand new engine and transmission. Utilising our extensive experience, every component, from crankshaft to pistons to camshaft profile, is selected to meet your requirements. You can trust us; we know what gives results.


Get the feeling you no longer have the fastest engine around or you are dogged by poor reliability then we can look at your engine, whatever its origin, evaluate it, make suggestions for improvements that meet your budget and then re-build it for you – the next best thing to a brand new Swiftune engine or transmission.

Competition Engines

Formula Junior

World champions, including the great Jim Clark, started their single-seater racing careers in Formula Junior cars and in the mid ’90s enthusiasts showed renewed interest in these nimble 1100cc cars.

Historic Minis

Historic Touring car racing across Europe would not have achieved its fantastic appeal without a gaggle of Mini Cooper S performing crowd-pleasing ‘David and Goliath’ acts at every round.

Bespoke Engines

With our 50 years of experience in A Series engine building, we can bespoke build both race and road engines using our specialist components and all tested on the dyno before leaving our workshop.

Rally Minis

The rising popularity of historic rallying in the UK and the revival of famous pan-European classic rallies has given many enthusiasts the chance to get behind the wheel of a Mini Cooper S.

Technical Notes

CSI distributor fitting instructions
Please read this instruction carefully. An incorrect installation can destroy the CSI and/or damage the engine! In case of any doubt, please consult an expert. Watch out for high voltage!


  1. Check the resistor value of the ignition coil. For 12 volt ignition coil more than 2.5 ohm. If the resistor value is too low it can cause overheating and/or damage the CSI. It is recommended that you use a Lucas DLB 105.
  2. It is recommended to use HT silicon leads (with resistance of at least 2 K ohm). If you want to use copper leads, always use resistor spark plugs (with resistance of at least 2 K ohm).
  3.  With the existing distributor still in place set the static adjustment at 10 degrees BTDC using the original timing marks from flywheel or crankshaft pulley, making sure that the rotor arm points to the number one spark plug. For a further check that the engine is at TDC on number one cylinder you will be able to insert feeler gauges for both valves (see photo).0542, 0505
  4. Remove the old distributor. The drive key is offset. Ensure that the larger section is to the top (see photo). 0521
  5. Disconnect all wires of the ignition coil. Determine the 12 volt power supply wire and connect it to the + contact of the ignition coil together with the RED wire of the CSI. Do not connect the wires yet. If the 12 volt supply is connected directly to the black wire the distributor will not work and may be irreparably damaged!
  6. Turn the ignition on. 0523
  7. Turn the CSI to the left until the led flashes; the number of times that the led flashed is the curve number that it is currently set to.0529, 0531
  8. Adjust with the help of a small Philips screwdriver to the right curve (see table). 0546
  9.  Slowly turn the CSI distributor to the right (clockwise) until the blue led lights continuously. The CSI is now adjusted to the static adjustment point. Tighten the CSI.0537
  10. Turn off the ignition and connect the black wire to the negative contact of the ignition coil.
  11. Assemble the distributor cap and connect the ignition cable, watch the order and keep the high voltage cables as far away as possible from the other cables (to prevent interference).0538
  12. Put the car into neutral and start the engine.
  13. If you are using a tachometer, this can now also be connected to the black wire.
  14. Check the adjustment with the help of a stroboscope and check that it is set on 10 degrees.
  15. If you want to change the curve number, turn the ignition on, (don’t start the engine) and remove the cap – you will see the led light flashing. If the led light doesn’t flash, crank the engine a little bit until the led light flashes. Select with the help of a small Philips screw driver, the right curve.

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Gear Ratios

Swiftune ATB Differential

What is an ATB Helical LSD differential?

The Automatic Torque Biasing Helical LSD differential, developed and patented by Quaife, provides smooth, constant traction for racing or slippery road conditions. It is ideal for Minis because it has no adverse effect on the steering of a front wheel drive vehicle so combating FWD torque steer and understeer.

The ULTIMATE Differential

The Automatic Torque Biasing Helical LSD Differential enables your Mini to accelerate quicker and corner faster. How? Simply by getting the power to the ground!

The Swiftune differential powers both drive wheels under nearly all conditions, instead of just one wheel. With a normal open differential much precious power is wasted through wheel spin under acceleration. This happens because the open differential shifts power to the wheel with less grip – along the path of least resistance.

The Quaife differential, however, does just the opposite. It senses which wheel has the better grip, and automatically biases the power to that wheel. It does this smoothly and constantly, and without ever completely removing power from the other wheel.

In cornering, while accelerating out of a turn, the ATB diff biases greater power to the outside wheel, reducing inside-wheel spin. This allows the driver to begin accelerating earlier, exiting the corner at a higher speed.Save & Exit

The Swiftune differential also controls loss of traction when the drive wheels are on slippery surfaces such as ice and snow or mud, providing the appropriate biased traction needed to overcome these adverse conditions. The drive is both constant and infinitely variable drive. Power is transferred automatically without the use of normal friction pads or plates seen in other limited-slip designs.

The ATB Helical LSD differential’s unique design offers maximum traction, improves handling by reducing understeer, curbing steering ‘fight’and puts the power where it is needed most. A definite advantage, whether you are on the track or on the street.

The ATB differential is extremely strong and durable, and since it is gear-operated, it has no plates or clutches that can wear out and need costly and regular replacement. There is no maintenance required to the unit, so once installed the unit can be forgotten, apart from the better road responses.

The Swiftune ATB differential is great for performance or track day Minis, racing or rallying. Racers don’t have to put up with locking mechanisms or spools that tear the steering wheel out of their hands when cornering. Because it behaves like an open differential during ordinary driving, street drivers will have trouble telling it’s there until pushing the cars towards its limits.

The Quaife ATB differential is proven in everything from SCCA Rallying to drag racing and Formula 1. It provides autocrossers with such an advantage, it has become “required” equipment for a winning effort.

Swiftune has exclusive rights to the Quaife patented ATB diff for Minis.

Get in touch

If you would like to get in touch, call us on +44 (0)1233 850843, email sales@swiftune.com or simply complete the form below.