Welcome to the latest instalment of our DIY Mini Restoration series! In this guide, we revisit the Bogus 2 Mini build, focusing on setting up the transfer gears. This guide provides instructions and practical tips to help you achieve optimal performance for your Mini. If you need technical advice or assistance, don’t hesitate to contact the Mini Sport team. Let’s dive in!
More Straight-Cut Transfer Gears: Noisy, Rattly, and Strong
Fitting the Straight-Cut Drop Gears
We start by fitting Mini Sport 1:1 straight-cut drop gears. These gears are designed to handle the extra power from the engine and reduce drag, ensuring less power loss during the transfer from the engine to the gearbox. In a Mini, these gears produce the characteristic chatter at idle and whine during acceleration. For any high-output engine, straight-cut drop gears are an essential part of the gear train specification.
Using a New End Casing
For this build, we are using a new end casing, identifiable by the sensor hole near the starter housing. Older casings can be refurbished with replaced bearings if necessary. This new casing also includes a crank breather hole. Always inspect the casing and bearings before fitment, just as you would with any build.
Checking Tolerances
Before bolting the gearbox to the short block, offer the end casing to the gearbox casing with the gasket in place to check the tolerance in the idler gear thrust washers. Roller bearing versions, often referred to as Timken bearings, are available from Mini Sport for enhanced performance.
Assembling the Transfer Gear Set
Here, you can see the inverted engine and gearbox with the full transfer gear set assembled, prior to attaching the end casing. Note that the bearing on the gearbox output shaft is a nylon casing type, which requires careful handling to avoid breakage. Some builders prefer to use the old-style roller bearings for the output shaft if they can find them.
Fitting the Primary Gear
After applying a dab of moly grease on the inner-bearing face, place the primary gear oil seal tool over the teeth. This inexpensive tool reduces the risk of damaging the critical oil seal. Ensure both the seal and the cleaned tool are oiled. Avoid touching the inside of the oil seal, as this can cause damage and lead to leaks from the clutch housing.
Installing the Primary Gear Guard
Don’t overlook the primary gear guard, as a leaking oil seal can cause significant damage. Make sure to place the C-washer correctly, pointing downwards with the engine at TDC. When checking the tolerance on the straight-cut primary gear, set it the same as a standard one. For race engines, allow a few more thousandths of an inch, particularly when using a cerametallic clutch, to prevent clutch loss due to tight tolerances when the clutch gets hot.
Explore Our Range of Products
Check out our gearbox components and accessories to find everything you need for your build. Stay tuned for more detailed guides in our DIY Mini Restoration series!
By using high-quality components, you'll ensure your Gearbox is perfectly set, leading to improved performance and reliability. Happy building!
Need Technical Help?
We're just a call or email away! Contact us for expert assistance with your Mini restoration project.
Our team is here to help with technical advice and top-quality products.
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
This guide is meant to provide general guidance and a step-by-step approach to build your Mini's Gearbox. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience.
Welcome to the latest instalment of our DIY Mini Restoration series! This guide focuses on the essential task of fitting the crank sensor for the Bogus 2 Mini build. Follow our detailed instructions and practical tips to ensure precise timing for your Mini's ECU ignition system. For expert advice or assistance, don’t hesitate to contact the Mini Sport team.
No Distributor Here... Crank Sensor Installation
Most modern ECU ignitions require precise timing information, and here’s how you can achieve that with the Bogus 2 Mini.
Fitting the KAD 36-1 Trigger Wheel and Sensor
Here is the KAD 36-1 Ford-style trigger wheel and sensor setup being fitted to Bogus 2. This enables us to use a Canems ECU and Jenvey throttle bodies. The 36-1 setup is the most common aftermarket ECU setup used, although other designs are available. This eliminates the need for the old distributor.
Prepping the Pulley
Adjusting the Kit Components
The KAD 36-1 Ford-style kit comes with a longer-than-standard bolt. This is done intentionally so customers can trim the bolt to the depth they require, depending on their engine’s setup and the pulley system they are running.
Marking for Timing
Timing marks on the chain cover and crank pulley are, at best, a vague guide to get an engine started. Mark the larger TDC tooth and the pulley indent in white paint to make them more discernible to a strobe light. With our Canems system, timing and mapping are completed on a dyno. For detailed guidance and support on fitting your crank sensor, get in touch with our team. We’re here to help you achieve the best results.
Securing the Timing Wheel
We ensured the crank-bolt washer was fitted to retain the timing wheel and crank pulley. We also used Loctite as there is no room for the usual lock-tab washer to retain the assembly. If the crank bolt works loose, you could lose your timing mark, resulting in incorrect initial timing. Avoid turning the engine anti-clockwise using this bolt, as it can move the timing mark. An oily crank thread can prevent Loctite from working correctly, so clean thoroughly. A large C-spanner was made to lock off the ring holding the timing wheel in place
Custom Bracket for the Sensor
Due to time constraints, we custom made a bracket normally supplied with the KAD kit to support the outer sensor bars. When setting up, ensure this sensor is both accessible and protected. Consider the types of belt used; here, we’re using a conventional V-belt. Timing was set by placing the timing wheel in place on the retaining cup, with the missing tooth on TDC, then turning nine teeth back from the gap and placing that tooth at the TDC mark. Different ECUs require different setups. The gap between the sensor and teeth should be between 0.75mm and 1mm, depending on the ECU.
If you have any questions or need help with your crank sensor installation, contact us today. Our experts are ready to assist with all your technical needs.
Discover Our Product Range
Explore our selection of engine components and accessories to find everything essential for your build. Stay tuned for more detailed guides in our DIY Mini Restoration series!
Utilising top-quality parts ensures your classic Mini engine is optimally performing, resulting in enhanced performance and reliability. Happy building!
Need Technical Help?
We're just a call or email away! Contact us for expert assistance with your Mini restoration project.
Our team is here to help with technical advice and top-quality products.
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
This guide is meant to provide general guidance and a step-by-step approach to build your Mini's Gearbox. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience.
Welcome to the latest instalment of our DIY Mini Restoration series! This guide revisits the Bogus 2 Mini build, focusing on the crucial task of setting up cam timing. Whether you're a seasoned enthusiast or a novice builder, precise cam timing is essential for optimal engine performance. Follow our detailed steps and practical tips to get your Mini running perfectly
Setting Up Cam Timing
Installing the Adjustable Duplex Vernier Timing Chain Kit
We started by fitting an adjustable duplex vernier timing chain kit. This kit offers the same strong chain as a fixed duplex kit but allows for more accurate cam timing. Precise cam timing is crucial, especially when using a non-standard cam. If cam timing is off, engine performance is significantly compromised.
Tip: Ensure the cam timing chain sits flat. If not, gears may need to be shimmed, indicating a worn crank. In cases of excessive wear, consider a new crank. Duplex chains reduce stretch, a common issue with standard simplex chains. Alternatively, dry timing belts offer performance advantages but require frequent changes.
Setting Up the Cam Timing Disc
Attach the cam timing disc to the crank. Using a piece of wire attached to one of the bolts through the backplate, set up an indicator after verifying that the crankshaft is at TDC (Top Dead Centre) on the requisite cylinder.
Confirming Full Lift on Inlet Valve Number One
Use a dial gauge to confirm full lift on inlet valve number one. This cam timing is set to 106 degrees, as specified by Kent Cams for the 286 cam profile. Release the six bolts in the front of the top cam pulley to allow for adjustment.
Tip: It's beneficial to have assistance during this step. One person should check the cam timing and lock off the vernier’s bolts, while the other monitors valve lift while cranking the engine. This process requires precision and patience.
Including the Oil Thrower and Cam Chain Tensioner
- Oil Thrower: Positioned on the end of the crank, the oil thrower helps protect the oil seal and reduces the chance of leaks. Some builders mistakenly leave this off.
- Cam Chain Tensioner: Even when upgrading to a duplex chain, a new tensioner should be fitted. Without a tensioner, cam timing will be imprecise due to chain flapping. Press the tensioner against the chain while cranking the engine in its normal rotation.
Explore Our Range of Products
Check out our gearbox components and accessories to find everything you need for your build. Stay tuned for more detailed guides in our DIY Mini Restoration series!
By using high-quality components, you'll ensure your Mini engine's cam timing is perfectly set, leading to improved performance and reliability. Happy building!
Need Technical Help?
We're just a call or email away! Contact us for expert assistance with your Mini restoration project.
Our team is here to help with technical advice and top-quality products. Get in Touch >
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
This guide is meant to provide general guidance and a step-by-step approach to build your Mini's Gearbox. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience.
Welcome to the next instalment of our DIY Mini Restoration series, where we revisit the Bogus 2 Mini build. This guide covers the gearbox and differential build, providing detailed instructions and practical tips to help you achieve optimal performance for your Mini. If you need technical advice or assistance, don't hesitate to contact us. Let's dive in!
Straight-Cut, Close-Ratio, and Four-Pin for Bogus 2
Choosing the Gear Set
We selected a straight-cut close-ratio gear set kit and used the original casing from the donor vehicle. This gear set is inspired by the original BMC Abingdon Special Tuning ratios but features modern heat treatment and materials for enhanced durability. For detailed information on the ratios, visit our website (Part No: MS4014).
Building the Gearbox
Here's the gearbox built up. We chose a 4.1:1 differential ratio to excel in hill climbs and sprints. A central oil pick-up has also been installed, along with an in-line magnetic oil trap, to reduce the risk of oil starvation during hard cornering. Useful websites can help you select the best ratios for your car. Discover our range of built gearboxes >
Selecting the Differential
We opted for a 'four-pin' differential to handle the power and torque. Various differential options are available, including limited slip (LSD) and automatic torque biasing LSDs, ideal for high-torque applications like turbocharged engines. This four-pin diff provides the same response as a standard diff but can handle more power. Mini Sport offers this kit pre-assembled (Part No: MSLMS0516).
Additional Gearbox Features
Magnetic Oil Trap
The gearbox includes a magnetic oil trap, positioned just above the diff casing on the back of the gearbox. This trap is directly in the oil flow from the central oil pick-up pipe and should be checked and cleaned each time you clean the drain plug magnet during oil changes (Part No: C-AHT54TRAP). Shop Now >
Gear Selector Rod Support
An aluminium collar, shown here without its O-ring, supports the gear selector rod. This non-OE part should be fitted in addition to the black oil seal. While not a replacement for the standard oil seal, it provides extra support to prevent significant oil leaks, especially when hammering home roll pins.
Need Technical Help?
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Important Checks and Tips
Inspecting a Secondhand Gearbox
When buying a secondhand gearbox, thorough inspection is crucial. This image shows the damage caused when standard transfer (drop) gears are used in a powerful engine, resulting in a badly worn outer casing.
Detecting Cracks
Some cracks may not be as obvious as this one in the third motion shaft bearing support, part of the central web in the gearbox. Kent Auto Developments offers a pinion bearing support housing kit that reinforces this central rib by supporting the end of the shaft, which is essential under hard acceleration.
Need Help with Gear Box Parts?
Contact us to find the perfect components for your Mini engine rebuild. Or use our Easy Parts Finder to identify the Mini Parts you need!
Damage Indicators
If you find a smashed second gear stripped in the gearbox, it indicates significant damage. Since the engine shares the same oil supply as the gearbox, ignoring gearbox issues can lead to engine failure. Discover our range of Mini Gearboxes and parts >
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
This guide is meant to provide general guidance and a step-by-step approach to build your Mini's Gearbox. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience.
From the Top: 7-Port Head Preparation
In our latest installment of the DIY Mini Restoration series, we dive into the intricate process of preparing and assembling the cylinder head for the Bogus 2 Mini build. Our goal is to provide you with a detailed guide to ensure your engine performs at its best. If you need technical advice or assistance, don't hesitate to contact our team at Mini Sport Ltd. Let's get started!
Step-by-Step Guide to Cylinder Head Preparation
Preparation of Mini Sport’s Secret Weapon
We began by preparing the 7-port head to Bogus 2 specifications. All 7-port heads are modified to customer requirements or can be purchased as raw castings for custom work. Safety gear is essential in the grinding area, which is sealed from the rest of the workshop. Our staff always wear a full-face mask and hood. Contact Mini Sport for your own custom requirements
The Finished Item: Flowed and Ported
We then flowed and ported the head with 37.7mm inlet valves and 31mm exhaust valves. All of our 7-port heads come with 31mm exhaust valves or larger. For reference, standard Rover 1275 valve head sizes are: inlet 35.58-35.71mm, exhaust 29.25-29.38mm.
Ensuring Tight Stud Fitment
When we screwed in the extra head stud by number-four cylinder, it felt tight. To prevent swarf from entering the bore, we masked the area off before running a tap to clear the stud thread. ARP studs, known for durability, feature an Allen key hole for easy installation and removal.
Choosing the Right Head Gasket
A BK450 (turbo-type or black top) head gasket is used for its durability in engines from 1275cc to 1400cc, especially under high temperatures and compression. This asbestos-free gasket fits both 9- and 11-stud heads.
Lowering the 7-Port Head
The head is carefully lowered onto the block, locating on the 11 ARP head studs. The four thinner rocker post studs were all of the longer length, which didn't pose any issues.
Using New Pushrods
We then used new 1275 pushrods. Always check previously-used pushrods for wear, as worn ends can affect engine tappets. New pushrods and followers can quieten an engine and enhance performance.
Double Valve Springs for Durability
It was decided we should use Double valve springs, as specified by Kent Cams (VS2), matched to the valves and cam. The Spring rating is crucial and should be defined by your cam selection.
Adjusting Rocker Shaft Post Spacers
The spacers were placed under each rocker shaft post to reduce the load angle between rockers and valves, compensating for head and block machining. We checked the Valve lift after installing the rockers.
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Fitting Roller Rockers
Mini Sport 1.5:1 alloy roller rockers (Part No: MSLMS0480) are fitted to allow wider and longer valve openings. These are set up similarly to conventional rocker assemblies, with a valve clearance of 0.016 inches defined by the Kent 286 cam. The head is torqued down in a spiral pattern, bolts checked three times to 45lbf/ft.
Installing a High-Lift Rocker Cover
A high-lift rocker cover is needed to clear the roller rockers. Mini Sport fits a cork gasket using spray glue to retain it on the rocker box. Avoid silicone gasket sealant as it can damage engines. Replace rocker cover grommets regularly to prevent oil leaks.
Using a Blanking Sleeve
To prevent overheating in cylinders three and four, a blanking sleeve (Mini Sport part: 11G176) is fitted in place of the thermostat. If you have a bypass hose on your water pump, block it off as well.
Fitting a Big-Bore Exhaust Gasket
A big-bore exhaust gasket (Mini Sport part: C-AHT381) is used, retaining the standard gasket setup. The gasket is finely trimmed to ensure maximum flow.
Need Help with Engine or Cylinder Head?
Contact us to find the perfect components for your Mini engine rebuild. Or use our Easy Parts Finder to identify the Mini Parts you need!
Modifying the Water Temperature Sender
The water temperature sender supplied with the ETB Digi-Dash2-Lite was not tapered, causing it to foul against the head. Some iron was removed from the head casting to allow proper clearance and tightening. This requires precision to avoid damaging the water jacket.
Ready to Build Your Mini Engine?
For additional technical advice or help with your Mini restoration project, contact the Mini Sport team. We're here to assist you with expert guidance and top-quality products.
Explore our range of engine components and accessories to find everything you need for your build. Stay tuned for more detailed guides in our DIY Mini Restoration series!
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
This guide is meant to provide general guidance and a step-by-step approach to restoring your Mini's Engine. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience. Safety should be your top priority.
Building an engine for your Mini is a rewarding challenge that every DIY enthusiast dreams of. Whether you’re opting for a standard road motor or something more specialised, a successful engine build is an incredible achievement.
Why Consider a Rebuilt Engine?
Finding a reliable rebuilt Mini engine can be tricky. Many enthusiasts share stories of mixed results when purchasing engines from various sources. If you’re not confident in your engine-building skills, consider investing in a professionally rebuilt engine. Trustworthy suppliers like Mini Sport offer top-notch engine-building facilities, ensuring quality and reliability.
Always consult with the experts! If you're unsure, reach out to the Mini Sport team for technical advice on your engine build.
Building the Short Block: Step-by-Step
1. Preparing the Block
Shotblasting and Honing: The pre-injection A+ block has been shotblasted, honed, and faced in-house. We used an offset-bored to 73.5mm (1380cc) and will run an 11.5:1 compression ratio. We have also fitted new cam bearings and oil bungs, along with new core plugs using Loctite 641.
Thread: During the block check, two stripped threads were helicoiled. This led us to drill out the original thread, tap a larger thread, and insert a helicoil to return it to the original size
Piston Fitting: Omega forged offset 1380 pistons are used. The 7cc dish is offset to aid combustion. The gudgeon pins are press-fitted into balanced and polished conrods, with the small end heated prior to fitting to reduce stress on the piston. Shop our full range of Pistons for your classic Mini here >
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3. Assembly Tips
Cleaning and Oiling: Clean the block thoroughly with brake cleaning fluid, oil the bores, and ensure the piston rings are oiled before installation.
Camshaft: Fit the cam followers and cam before the crank for easier access. A good sign that cam followers fit well is that they will fall into position under their own weight. Discover our full range of Engine Components >
Installing the Crank: Lower the crank into position with the conrods for cylinders one and four resting to the front and two and three to the rear. The main and big end bearings being used have been matched to the crank during the dry build. Use moly grease on ARP conrod bolts and cap bolts to prevent binding and ensure correct torque values.
Need Help with Engine Parts?
Contact us to find the perfect components for your Mini engine rebuild. Or use our Easy Parts Finder to identify the Mini Parts you need!
4. Final Steps
Main Cap: Make sure you fit the main cap thrust washer round the correct way, if not it can bind to the crank causing damage. Fit the Mini Sport steel centre main bearing strap to reinforce the bearing cap and reduce crank flex at high RPM.
Torque: We torqued the main end caps to 65lbf/ft and big ends to 35lbf/ft. Once complete recheck and verify the crank can be turned. If not, slacken off the bolts and re-torque. If it will not turn smoothly then something is binding and all the bearings should be rechecked.
End Float Check: Ensure the crankshaft end float is within standard road car tolerances (0.003-0.005 inch for this engine).
Oil Pump Preparation: Check and clean a new standard oil pump for burrs. Prepare the block to accept a four-bolt oil pump for stronger fixing. The gasket at the end of the block needs to be checked, we modified the gasket to ensure free flow to the oil drain holes.
TDC Verification: Use a dial gauge to check Top Dead Centre (TDC) for accurate timing.
This is done with a dial gauge, magnetically mounted onto the block. Sometimes the TDC timing mark on the standard crank pulley can be wrong and, when it comes to timing, every degree counts towards getting the best power out of the engine.
Get Expert Help!
If you’re looking to tackle your Mini engine build but need guidance, don’t hesitate to contact the Mini Sport team for expert advice. We offer a wide range of products, from engine components to tuning solutions, to help you achieve the perfect setup.
Whether you’re a seasoned builder or just starting, remember: every engine build is a journey. Enjoy the process, and happy building!
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
This guide is meant to provide general guidance and a step-by-step approach to restoring your Mini's Engine. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience. Safety should be your top priority.
When it comes to enhancing your Mini's performance, your Mini's Brakes are a crucial aspect that demands attention. Most upgrades focus on the front end, ensuring your Mini can handle the demands of modern driving while maintaining its classic charm. Let's dive into the details of our recent brake enhancements, ensuring every component is optimised for safety and performance.
Rear Brakes and Handbrake Quadrants
We started by replacing the rear brake backplates with Mini Sport pre-built replacement rear brakes. These units come with Mini Sport alloy Minifin replica brake drums, which significantly improve brake shoe cooling and match the Cooper S/Rover rear drum offset.
To ensure the longevity and smooth operation of the handbrake quadrants, we used 3-in-One White Lithium aerosol grease. This product not only protects the quadrants but also keeps the handbrake cable well-lubricated.
Caliper and Hose Installation
Using Aluminium Calipers
When using aluminium calipers, it's important to include both a flat washer and a spring washer when bolting it to the hub. This spreads the load effectively. In contrast, the standard cast iron calipers (like the heavy AP items) do not require an extra flat washer. We utilised Mini Sport's alloy four-pot calipers for superior braking power.
Connecting Steel Braided Hoses
Goodridge steel braided hoses were chosen to connect the calipers to the front subframe. These hoses require a copper washer, which should be replaced if the hose needs to be undone. This ensures a reliable and leak-free connection.
Securing Hoses to the Subframe
The inboard end of the Goodridge caliper hoses is secured with a plain nut and a special anti-shake washer, locking it to the front subframe. This type of aggressive lock washer is essential here. To avoid twisting stresses, always fit the hoses to the calipers first, then to the subframe.
Vented and Grooved Rotors
The Mini Sport vented and grooved rotors can be mounted in either direction. When the grooves point with rotation, more air is pulled into the pad, enhancing cooling but increasing noise. If the grooves point the other way, brake noise is reduced, but cooling is less effective in motorsport conditions.
By following these detailed steps, you can ensure your Mini's braking system is both reliable and effective, ready to meet the demands of any driving scenario. Remember this is just a guide, if you are unsure about any steps involved in this process contact a trusted professional. The Mini Sport team can be contacted for advice, recommend nations or to book an appointment. Get in touch today!
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
Throughout the restoration process, using high-quality products ensures durability and performance. Visit our website to find all the parts mentioned in this guide.
If you need any help or expert advice, don't hesitate to contact us. Happy restoring!
This guide is meant to provide general information and a step-by-step approach to restoring your Mini's front subframe and suspension. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience. Safety should be your top priority.
Heavier Duty but Not Difficult: Upgrading Your Mini's Front End
Upgrading the front suspension of your classic Mini can seem daunting, but with the right parts and a meticulous approach, it's a straightforward process. At Mini Sport Ltd., we specialise in providing top-quality components and expert guidance to help you enhance your Mini's performance.
Standard Rubber Doughnuts (Cones) and Top Arms
We started by fitting standard rubber doughnuts (cones) with the original top arms, refurbished with new pivot shaft kits. For adjustable ride height, we used Mini Sport’s Adjusta-Ride suspension trumpets, renowned for their quality.
To reduce twist and increase the stiffness of the front subframe, we added fillets and seam welds along the suspension towers. This, along with solid mounts for Mk4-on front subframes, helps with finer steering and handling but may also increase noise, vibration, and harshness.
Installing the Adjusta-Ride Kit
Mini Sport’s Adjusta-Ride kit, equipped with a grease nipple to prevent thread seizing, was installed. It also comes with a cover over the thread to prevent water damage. During a trial fit, we found the thread on the urethane bump stop was too long and shortened it by 10mm for easier future removal.
Pre-Assembling on the Bench
As with the rear subframe, pre-assembling components on the bench simplifies the process. We used copper grease on various parts, such as the bump stop and its locknut, to prevent seizing and ensure easy removal in the future. This step is crucial, especially in water-prone areas.
For help or advice on building your Mini's subframe, contact us today, or visit our Easy Parts Finder to identify the parts you need.
Securing the Pivot Shaft
Use new bolts to retain the pivot shaft. Clean the threads for the captive nuts on both sides of the subframe with a UNF tap before fitting the plate.
Fitting the Dust Cover
Pull the dust cover on the forward part of the top arm back over the outer edge of the casting before fitting the top arm. This aids the fitting process. Once the pivot is in place, push the dust cover back into its correct position.
Fit the polyurethane rebound buffer, or droop-stop, while the spring is still compressed. Use a washer to spread the mounting screw load on this all-plastic type, as self-tappers usually ruin the captive nuts.
Compressing the Rubber Doughnut (Cone)
Using a Mini Sport suspension compressor, we compressed a standard rubber doughnut to easily install the top arm. Later rubber doughnuts tend to have a metric internal thread, so ensure compatibility with your compressor tool.
Adjusting the Tie Bars
For this build, we selected Mini Sport’s fully adjustable Group A race-proven tie bars. The original standard tie-bar was used to gauge the required length of the adjustable one. Copper grease was applied to all relevant parts to improve longevity and ease future adjustments. Note that tie-bar adjustment primarily affects the caster angle but also impacts the toe angle.
Setting Up the Bottom Arms
Mini Sport’s adjustable bottom arms, tested on rally cars for durability, were installed. Using the standard bottom arms as a reference, we ensured the correct setup length to allow for front wheel camber changes. These arms, with their large Rose joints and built-in dust guards, offer both reliability and adjustability.
A towing eye was fitted, essential for any track or motorsport car. We also used a genuine subframe bolt strap with water seals, eliminating the need for an additional person inside the car.
Mini Sport’s front top damper mount, designed for rally-style abuse, was installed. This robust component features a removable bolt and a boxed bracket for added strength, ensuring long-lasting performance under demanding conditions
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
Throughout the restoration process, using high-quality products ensures durability and performance. Visit our website to find all the parts mentioned in this guide.
If you need any help or expert advice, don't hesitate to contact us. Happy restoring!
This guide is meant to provide general information and a step-by-step approach to restoring your Mini's front subframe and suspension. It is always recommended to contact a trusted professional if you are unsure about any part of the process or lack the necessary tools and experience. Safety should be your top priority.
Steering Rack: Get It Right the First Time
Changing a steering rack can be a real hassle later on, so it's crucial to get it right the first time. Follow our detailed steps to ensure a smooth and efficient installation process for your Mini.
Check and Replace Trackrod Gaiter
During our careful inspection of the steering rack, we discovered a tiny split in the trackrod gaiter. Though the split was small, the boot was full of water. To prevent future issues, we replaced the boots and re-lubricated the rack.
Inspect Trackrod Ends
We examined the trackrods for pitting and wear in the ball joints. Surprisingly, despite the water intrusion, there were no problems. While manuals typically specify that the rack should be oil-filled, we found that packing it well with LM grease is a more practical alternative. It’s less messy and less prone to draining away.
Standard-length trackrod ends were fitted next. By counting the number of turns while removing the original rod ends, we ensured that the tracking would be approximately correct. Precision tracking should be verified later using specialised equipment.
Upgrade your Mini's performance with our high-quality track rod ends. Shop Track Rod Ends Now!
Fit Foam Washer for Noise and Leak Reduction
Before bolting the steering column in place, remember to fit the foam washer over the steering column's splined shaft. This helps seal a large hole in the bulkhead, reducing noise and preventing water leaks.
New Nyloc nuts and washers were fitted to the rack’s U-clamps. At this stage, the nuts are not fully tightened since the column still needs to be adjusted. Once the steering column is fitted, adjust it to the correct angle before tightening the U-bolts. Ensure the rack’s splined shaft aligns perfectly with the steering column inner shaft to avoid dangerous stresses.
Final Positioning and Vibration Reduction
Here’s the rack fitted and held in place with its special U-clamps. Note the anti-vibration plastic strip, a feature of later Minis. This simple strip reduces resonance in the rack and helps prevent the bolts from working loose. This end of the rack defines its position relative to the bodyshell and must be fitted before the front subframe, although final angle adjustments can be made later.
Proper installation of your Mini's steering rack is essential for a smooth and safe driving experience. By following these detailed steps, you can ensure your Mini performs at its best. For any assistance or to have a professionally fitted Steering Rack, don't hesitate to contact the Mini Sport Team.
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
Your classic Mini is more than just a car, it's a symbol of classic style and a joy to drive. But wouldn't you love a touch more confidence and control behind the wheel? At Mini Sport Ltd., our specialise in helping you enhance your Mini's driving experience.
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Rear End: Assembling the Lighter Mini Subframe
The iconic Bogus 2 rebuild project continues at Mini Sport Ltd.! In our previous guide, we delved into the steering rack. Now, let's shift gears and focus on bringing the rear suspension of this classic Mini back to life.
Assembling the rear subframe on a bench not only simplifies the process but also reduces the risk of damaging the shell. Here’s a step-by-step guide to ensure a smooth assembly.
Initial Assembly and Preparation
Assembling the rear subframe on a bench makes life easier and reduces the chance of damaging the shell. Initially, only the trunnions are fitted, as the heavy rear radius arms make subframe installation more difficult.
The mounting points for the rear trunnions were covered during powder coating, so they needed cleaning before fitting the trunnions. The threads were also checked and cleaned with a wire brush, nut, or dye if necessary.
Fitting the Trunnion Kit
An ultra-light alloy DSN Classics trunnion kit was fitted, shown here with replacement steel trunnion pins and Mini Sport poly bushes. The trunnion pins are standard Mini items. Apply some copper grease on the shaft and thread to prevent the trunnion from seizing. The trunnions are fitted with a Nyloc nut, but not finally tightened until the subframe is in place at all four corners.
Installing the Rear Subframe
Forward Pin Adjustment
The nut on the forward pin is not fully tightened before the subframe is bolted into the shell. Since nobody seems to make the two-pronged tool needed to lock off the trunnion pin, improvisation is required.
With all the trunnions fitted and positioned in the direction of their mounting points, the rear subframe is ready to be fitted. The front trunnion mountings need to be cleared after the shell has been painted. It’s critical to get some copper grease into these captive nuts, as this is a rust-prone area of the shell.
The heelboard in the British Motor Heritage-supplied floor pan needed modifying during trial fitting. Access to the captive nut wasn't possible without elongating the hole before painting. A Dremel is useful for this job, but protect the thread carefully.
Lifting and Aligning the Subframe
Lifting the subframe is at least a two-person job due to the nuts and bolts alignment required. Get at least one bolt in each trunnion first before attempting the second to avoid scratching the paint. Take care when inserting the mounting bolts into the heelboard captive nuts. Support the subframe to relieve the load off the bolt. These points are crucial for suspension geometry, especially for older captive nuts that are difficult to replace if stripped
Fitting Radius Arms and Damper
With the rear subframe in place, tighten the front and rear trunnion Nyloc nuts before fitting the radius arms. Before installing the radius arms, fit the new knuckle joint into each arm on the bench. Ensure the knuckle joints are properly packed with grease, using a new nylon cup.
Adjustable Rear Camber/Tracking Brackets
The Mini Sport adjustable rear camber/tracking brackets had to be modified to fit the DSN leading trunnion. This modification is due to the more bulbous outer radius of the trunnion compared to standard camber brackets. Tighten the adjustable rear camber/tracking bracket. Fine adjustments will be done once the car is back on the floor and fitted with its correct wheels.
Using Copper Grease
Apply copper grease to the inside surface of the connecting rod between the rear cone and knuckle joint. This ensures the cone remains removable in the future. Apply copper grease to the outer shaft at the cone end. When positioning the offside Adjusta Ride cone, ensure the grease nipple is accessible to avoid difficulties posed by the battery box.
Fitting Spax Dampers
When fitting the rear Spax dampers, they were found to foul the edge of the radius arm. Trim the upper edge of the arm to clear the damper. Mini Sport prefers not to use the steel cup washer at the top of the rear damper mount rubber bush, as it causes chatter. Let the bush sit against the wheel arch surface to minimise noise.
Ensuring Clearance
Ensure the damper top thread clears the fuel tank when the Mini is on its wheels. Trial fit a standard tank to verify. Finally, fit the Mini Sport dry-suspension-specific handbrake quadrants. Remember to secure the quadrant shaft with the tiny split pin and washer.
Want to read Keeping Your Mini Alive 6th Edition Magazine? Download the PDF here
Don't miss out on the rest of the Bogus 2 Series!
This blog series is your go to for a guide to taking your Mini from a bare shell to a road-worthy classic. Check out the rest of the series for tips and advice from our Mini Experts for every stage of your Mini restoration!
Need help or advice on upgrading your Mini's rear suspension? Contact us today for expert guidance tailored to enhance your driving experience. Let's restore your Mini together!