BMW V8 Cylinders
Engine Blueprinting is the art of defining tolerances to an acceptable minimum. The wisest and most important process would be to have the entire bottom end, i.e. crank, conrods, pistons, flywheel /flex plate, front damper pulley etc, to be balanced from “end to end” or harmonic balancing as some like to call it. This process is an important part of the engine blueprinting process which obviously entails extensive machining and polishing works, and when all put together enables an engine to rev more freely without excessive vibrations prevalent in mass production engines, thus extending the life of an engine. Simultaneously, your bores can be checked and a new set of rings and crank bearings installed.
BMW V8 crankcase designs have blocks which have a thin walled aluminium sleeve which is cast into the block at the time of manufacture. NIKASIL or ALUSIL is a electrodeposited lipopholic nickel silicon carbide coating lined cylinder bores that are prone to scratching or gauging which is an extremely costly repair, (there is no quick fix solution as good old fashioned cylinder reboring to the next oversize!) It has always been said, “there is no replacement for displacement”, but with these engines the only way to increase cubic capacity is by “stroking” the motor thus increasing the crankshafts stroke. By increasing the bore diameter would require changing the entire crankcase.
The best advice we can give any reader of this article, is to keep all the cars air filtration component areas well sealed and regularly checked for cracks and any openings. Always use the best possible gasoline with the lowest sulfur content and change the engine oil and oil filter with an ‘A’ grade quality replacement lubricant and filter at regular intervals. These thin sleeves usually develop cracks at the top of the bore due to overheating or stress.
Sulfur content in fuels is responsible for either pitting or thinning the NIKASIL walls on the cylinder sleeves and when dust particles enter this environment they can start tiny scratches in the NIKASIL film, developing into more severe damage, causing NIKASIL and ALUSIL bore coatings to eventually crack and even flake off, resulting in bore to piston ring failure. This is probably the number one reason for smoking V8 engines besides worn valves and guides. BMW will only guarantee the cylinder linings for 150,000 km's on a new engine with a stringent service history.
An essential preventative measure to the problem is to ensure that all the injectors are serviced by a competent fuel injector specialist. Injectors that over fuel or spray in an irregular pattern, will also lead to “washing”, a term applied, meaning that an excessive amount of fuel deposited onto the cylinder walls, thus thinning the lubricating qualities of the essential oil required for piston ring and piston to bore scuffing qualities is present.
Cylinder head gas flowing is also a very important part of blueprinting a V8 BMW engine. Camshaft re-profiling to an acceptable limit also ads gains and immense kW, HP and Torque depicted by what is referred to as an engines torque curve which can be altered by dynamometer chip tuning.
We have many more power gains in the process of engine blueprinting, but for now I’m sure the above will suffice, and most importantly, keep your engine well serviced. The above should be a stern reminder that this is an expensive engine affair, with a total engine rebuild amounting to at least 60 hours of labour, so don’t skimp here.
For more information and a Free quote CLICK HERE “BMW V8 Engine Specialists / Spares” or Call Centre : 0861 7777 22
