The Flex-Hone® for MGB Cylinder Blocks

MGB sports cars are diminutive roadsters that were built in Britain and especially popular in the U.S.  Named after Morris Garages, a car dealer and automotive designer, the MG Car Company manufactured more than 500,000 MGBs from 1962 to 1980. Except for the V8 version, all MGB automobiles featured the BMC B-series engine, a straight-4 built by the Austin Motor Company.

Engine Restoration and Rebuilds

Today, some MG owners buy conversion kits and replace their roadster’s original powerplant with a more powerful crate engine. MGB purists, however, adopt a different do-it-yourself (DIY) approach – the engine rebuild. For Sports Car Services, a repair shop that rebuilds British sports cars in a six-bay barn, restoring an MGB engine means using the Flex-Hone® tool from Brush Research Manufacturing (BRM).

Why Ball Hones are Better

Last fall, Sports Car Services started work on a ring and valve job at its auto shop in rural Westminster, Vermont. After boxing the head, a mechanic named Warner used a ridge reamer, dropped the oil pan, and removed the piston and connecting rods. The engine restoration specialist then ball honed each cylinder with BRM’s Flex-Hone® tool, imparting a uniform surface finish that, in Sports Car Services’ own words, “is simply unobtainable with conventional rigid-stone tools”.   

The Flex-Hone® for Engine Cylinders

Built with a stiff metal stem and flexible nylon filaments, the Flex-Hone® produces the optimum surface finish in any type or size cylinder. Used by car mechanics and the automotive industry alike, BRM’s versatile honing tool  is ideal for engine block restoration, cylinder deglazing, and auto parts deburring. As Sports Car Services explains, “because the globules of abrasive are suspended on nylon filaments, the tool conforms to the shape of worn cylinder bores”.

Plateau Finishing

Self-centering and self-aligning to the bore, BRM’s cylinder honing tool is also self-compensating for wear. By reducing the peaks produced by prior machining operations, the Flex-Hone® tool produces a substantially flat or plateau finish, allowing piston rings to seat properly. The unique cross-hatch pattern that flexible honing creates also aids in lubrication control and retention. Additional benefits include less blow-by and less friction.

What’s Your Automotive Application?

“Flex-Hones are both the world’s most sophisticated cylinder wall prep tools and arguably the easiest to use,” Sports Car Services explains. Are you an engine builder or an automotive restoration specialist? Do you use the Flex-Hone® tool for cylinder wall deglazing? Let us know by commenting on this blog entry.