Steady Eddy
My first visit to Mini Spares must have been over 12 years ago and while buying the usual go faster bits, I enquired about a Saturday job. A very lean and handsome Keith Calver could only offer me full time employment. I declined and subsequently have spent a small fortune over the years and drunk far too many pints of beer with K.C.
I've owned a series of Minis over the years. Each time the horse power figures and the sums of money involved have become bigger and bigger. Ultimately I ended up with my "Cosworth" Mini. A fully road legal car, powered by a home built, 1600cc, dry sumped, all steel Ford Cosworth BDA engine. The Cosworth Mini was sold to finance my big step into Modified Production Saloon car racing. The Falken Tyres Championship basically caters for road legal cars. All steel panels, non adjustable suspension and the same engine/gearbox combination as the car left the factory with. The class structure means the Mini competes in the up to 1600cc category.
After a couple of reasonable season's racing, regularly running in the top 6, a major off at Donington Park resulted in a car which I felt was beyond economic repair. This gave me the opportunity to either retire or build a no expense spared Mini Racer. I opted for the latter of the two options.
The car was built up in Mr Calver's double garage with full access to his rather large Snap On Tool Chest. Keith had talked Martin Short of the "Roll Centre", into building the ultimate Mini roll cage, and my car was used for this project. I believe that this was the first of its type and subsequently developed into the more recent "Bill Sollis" cage. To say it's a work of art is an understatement and far superior to anything else on the market. - See Keith Dodd's statement in the last Mini Tech News.
As previously mentioned, suspensiqn must be non-adjustable and no rose joints are allowed, although "Hi-Lo's" are permitted. The front suspension consists of stretched bottom arms and heavy duty Mini Spares tie rods with uprated bushes. Shock absorbers are adjustable "Koni" and I can
only confirm what the guys at Mini Spares have discovered with their project car and that is that the Koni shocks appear to have superior performance to that of others on the market. The steering rack has a Jack Knight pinion in it which reduces the lock to lock from a standard ZY2 turns to something just over Z turns. Rear suspension once again uses Koni shocks and a rear anti roll bar is fitted - another K.C. development.
Wheels and tyres are an important combination on any racing car. Tyres are obviously "Falken" and are 165/HR70/10. A common practice when racing with road legal treaded tyres, is to have them buffed. This basically involves fitting each tyre on a wheel and inflating it to its normal operating pressure. By mounting the wheel and tyre into a large lathe, the tread can be cut back to any depth the driver requires. Believe me, it might sound crazy buying a new tyre and cutting most of the tread off, but it makes a huge difference to the life expectancy of the tyre and more importantly the way the car goes round corners.
In the wheel department, I opted for the best money can buy. In my opinion that equated to "Spectrum", three piece wheels. They must be the lightest wheel available and with the added advantage that a damaged rim can easily be replaced. I also think that they look the"b******s". (we don't say "b******s" in MTN, it just pisses people off. G.A.)
Brakes have proved a bit of a problem over the last season. Using the "Spectrum" wheels, it has proved very easy to fit the standard Mini 8.4" diameter disc and caliper under a 10" wheel. With some modification to the master cylinder, the brakes proved adequate when used with 171 pads. As the 171 supply dried up and the asbestos free equivalent proved next to useless, a replacement was required. Competitors in the championship have reported excellent results with the Mini Spares supplied carbon metallic brake pads. Unfortunately these are only available in the Metro caliper size. To this end, a pair of Mini Spares aluminium 4 pot callipers will be tried this season with carbon metallic pads.
Now to the interesting bit you have all been waiting for, the engine and gear box. Starting at the bottom with the gearbox. I kept the Jack Knight 4 speed Dog Box from the Cosworth Mini and with the help of Geoff Gibbons at JKD this unit was rebuilt into a new case and was upgraded to the 5 speed unit.
The limited slip differential is a cam and pawl type and was another item carried over from the Cosworth Mini. This type of differential, people generally give a hard time. The main criticism being, that it wears out very quickly. I've owned this unit for at least 8 years and have had no problems
whatsoever. In that time, I've only replaced the pawls once. I feel there are two main reasons for this criticism. Firstly, the differential is designed as a tar mac unit and is not really suitable for off road. Secondly, a good quality synthetic oil must be used and more importantly used at the correct temperature. More about that later. Right from the beginning, the engine had all the expensive bits thrown into it. Reliability was the name of the game and to that end - touch wood - I've experienced no problems what so ever over the last 4 years racing. The engine is based around
a Mini Spares supplied EN40B forged 86mm strokecrankshaft. This when combined with Omega 73.5mm pistons, gives an overall engine capacity of 1460cc. This season I've purchased, once again through Mini Spares, a 1 off set of forged 74mm Omega pistons, which will take the engine out to 1480cc. The block is a Pre A+ with a solid centre main and to help hold the whole lot together a 4 bolt steel centre main cap is used.
Another absolute must is to regularly replace the crankshaft pulley/damper, with the big engines they seem to deteriorate very quickly. The engine is built, tested and maintained by Phil Hepworth of Race spec, Warrington, Cheshire. This company was formally Howley Racing and was responsible for the group A Metro turbos. To help keep the pistons as cool as possible on these units, an oil spray system was developed. This piston cooling technique has been built into my engine. Although not strictly necessary on a normally aspirated engine, I felt that the benefits were
worth the extra expense.
Since starting racing I've always used the Mini Spares ultra light steel flywheel and back plate and this has proved 100% reliable. For the 94 season I will be trying a "Manx Racing" , aluminium flywheel and steel back plate. The complete assembly weighs in at a little over 101 b's and I hope it will contribute to an improvement in performance this season. Another item from Manx Racing which although it will not be on the engine this season, I intend to try as soon as possible and that is a gear drive for the camshaft. The complete set up is lighter than a chain or belt assembly and does not suffer from stretch. This means accurate cam and ignition timing. This leads me nicely into camshafts. When the engine was first built, Keith Calver approached "B.H.P. Development", in the USA. Various items were imported such as a special exhaust manifold, the first 4 bolt steel main centre cap and a camshaft and followers. The cam proved very successful and provided the engine with a good spread of power and torque. Subsequently I've tried the Kent MD310 scatter and for the 94 season I will be trying a scatter cam from Steve Witton at M.LD.
The cam pushes against Mini Spares Roller Rockers, which in turn sit on top of a "Race spec" prepared big valve head, using offset exhaust valves. To help hold this lot to the block with a 12: 1 compression ratio, is an uprated stud and nut kit, from you guessed it, your favourite North London
Mini part supplier. (Are you being paid for this? G.A.).
Carburetion is split 48 DCOE SP Webers, which have undergone some important modification. Everybody always improves the air flow of the cylinder head, but never the carbs. Thinned down butterflies and spindles, modified Auxiliary vents and home made 38mm chokes, complete the picture.
Not to forget full radius ram pipes and K IS... N filters. The exhaust system as previously mentioned, is made up from a 3 into 1 "B.H.P. Development" manifold and a Peco exhaust box, which just keeps the whole thing within the noise regulations. A very important development has been the "Thermo Tec" exhaust wrap. K.C detailed the benefits of this product in the last issue of Mini Tech News. Needless to say, with the carburettors sitting on top of the exhaust manifold, the reduction in exhaust heat is very welcome.
Lastly engine oil. It never ceases to amaze me how many people bolt on huge oil coolers, whether on road or race motors and simply overcool the oil. Oil has an optimum operating temperature and really wants to have a minimum temperature of 85° c to stand any chance of doing its job properly. This in my opinion is even more critical with a Mini, where a unique situation exists, in that the oil is shared between the engine, gear box and final drive. Oil technology has moved in leaps and bounds in recent years and things are very different today compared to when the Mini Cooper left the factory with an oil cooler fitted as standard. I see no reason for a road legal, normally aspirated Mini, to run an oil cooler. In fact on my race car I threw the cooler away and very rarely see oil temperatures over 120°c. This is quite an acceptable figure with todays synthetic oils. I personally use 'Torco Oil" and having used it now for over a season's racing I would not change.
50 what does all this add up to. In financial terms probably in excess of 6k for the engine and gear box. In racing terms a lightweight, powerful, front wheel drive car designed over 35 years ago which can compete with more modern machinery. In my cars case, it's only lacking a good confident driver before its first race win is chalked up. Keith has nicknamed me "Steady Eddy", but I'll have to prove him wrong. I must just thank a few people who have made it possible for me to go racing: - Keith Calver - Mini Spares; Simon Bird - CA.M.; Oave Bass - O.J. Bass IS... Co.; James Humphrey - Unicom; Geoff Gibbons - J.K.O.; Phil Hepworth - Race spec; Mike Sharp - Stay Sharp Gym; Mad Bob - Cv.G. Signwriters; Steve Clark - Torco(Thermo Tec; Martin Short - Roll Centre.
lan Goldie