By Dean Sprague
This is the second installment of our trilogy, my son’s project. The MGB GT is now running and driving; rather well actually not yet complete but we are at a good stopping point. The next step is to start putting some miles on the car so we can further diagnose additional work that will be required. There is always additional work required we just don’t know what it is yet. In the mean time we are working on the Mini and the Volvo.
My son Jason and I are “restomoding” his 1980 10” wheeled classic Mini Cooper. This is a “real” British Mini that we are re-powering with Japanese internals. This is not a modern German owned British Mini powered by Mexican, French or German Internals.
His original objective was to convert this existing 998cc Austin Mini into a Honda V Tech powered retro “mini” rod while maintaining a completely stock appearance from the exterior and the cockpit. For you hot rod guys this is known as a “sleeper”.
Unfortunately this project, like my Volvo and many other projects, evolved into an unanticipated start from scratch effort. In hindsight it would have been much easier to simply unscrew the radiator cap and slide a new Mini under it. Wait a minute; we are doing that except we also replaced the radiator cap! The major problem was the original body. It was so rusty we decided it was not cost effective to restore it so we started looking for a better one. I think I mentioned in an earlier article that we found a late model 1992/93 British Mini that was built for and sent to the Japanese market. It was being parted out in Toronto Canada where it had arrived via New Zealand. The body was almost perfect and ironically came in a black body with a white top and red interior Jason’s dream color combo. We also found a mint late 90s B16B Honda V-Tech Japanese spec (for Japan only) drivetrain in California. This engine is built from a short stroke 1.8-liter block with factory upgrades giving it a 8600 rpm redline that renders it just short of a full race engine. We have since changed the transmission from the original close ratio 5 speed to a less desirable but taller geared 5 speed transmission from an Acura Integra LS to better off-set the smaller 10” wheels on the Mini. We did install a mild limited slip differential as part of the transmission rebuild. Anything stronger and the torque steer would rip the steering wheel from your hands. We also installed a lightened flywheel and completion clutch assembly. Then Jason found a tuned ceramic-coated header that just clears the grill. This combo should deliver something in the area of 200 plus HP at the wheels propelling a 1300 pound car a combination that will go much faster than I will drive it. Editor’s note: a friend with a similar conversion had it computer limited to 100MPH because as his wife said: “It gets a little squirrely at 100”
We have since fully serviced the engine including upgraded ignition wires, adjusting the valves, installing new distributor cap and rotor, timing belt along with water pump, cam and crank seals. He had the fuel injectors cleaned and bench tested and changed the ECU from an OBD ll to an earlier special remapped OBD l. This modified ECU is intended to focus on maximum engine performance only with no pollution distractions. We changed and adjusted everything that we could because once we stuff it in the body anything beyond changing the plugs, oil, filter or adjusting the belts will require removing the entire drivetrain.
We have cut, shaped and welded the engine bay until the complete driveline and sub-frame assembly actually fit in the very limited space. This included accommodating an air-conditioning system including the compressor, condenser, drier and refrigerant lines with out extending the front end. This required removal of the inner fender wheels, over half of the right headlight bucket and grill widening plus several indentures in the firewall and stretching the left front cowling a bit. Calling this a tight fit is an understatement but like they say about great spaghetti sauce “if it good it’s in there” and so far it’s all-good!
When these cars were being constructed and marketed every effort was made to sell them at the lowest possible price point. These were first and foremost economy family cars. This meant cutting corners anywhere they could. The bodies while very cute and amazingly efficient were not designed to withstand the ravages of time. The typical life span for the body tub when left to the elements was probably about 5 years. If you actually want to keep one of these cars there are a few deficiencies that must be addressed. In response, we are undercoating the floor pans again and properly sealing all internal sub frame assemblies. We are further insulating by bonding the entire interior with a waterproof sound and heat barrier material. We are also using a POR 15 type product in the doors, trunk and undercarriage where needed. We are doing everything possible to assure that the body will survive because Jason will probably keep this car for 20 years or more.
Our next step is to finish the blocking (contour sanding) on the body. Since Jason wants to retain the original color combination (black) the sheet metal must be really flat so it will reflect light like a mirror. This kind of prep will take a little extra time and probably at least one more primer-sanding coat. Even British Leyland didn’t get them this straight.
When we finally get it painted then we must run the fuel lines, hydraulic lines, wiring (including the battery cable) and anything else that will be attached to the firewall. The entire sub frame, engine, transmission, suspension, axels, brakes and steering must be completed as a unit before we can set the body down on the drivetrain. Once installed there is no room to get to the firewall. However, the rear wheel carriage, brake assembly and suspension can be installed anytime after painting and undercoating.
We will keep you posted but our goal is paint in the early spring and rolling on its own wheels but probably not running or driving by summer. I think we are converting a British export Mini to Japan into what might be considered a full Japanese British Mini if there is such a thing.
