Continued advancements in the tooling and installation process means that we can produce premium quality valve guide repairs, and upgrades, in the most efficient manner.
 

Superior Quality Since the early 1970's K-Line has run numerous dynamometer tests in conjunction with major production engine builders and O.E.M.'s. Repeatedly the Guide-Liners and has out performed cast iron guides and has become the approved method for rebuilding. In fact, these tests have found the Guide-Liners to be up to three times more durable than cast iron. Further more, the minimisation of both guide lubrication and guide to stem clearances have failed to induce either a seizure or cause metal transfer.  Ford, G.M., Caterpillar, Cummins, White Engines, Detroit Diesel-Allison and others have tested the product and confirmed K-Line's Guide-Liner system as an approved product for use in rebuilding their engines.

Fitting and Fettling Liner Shown in Red

• Increased Efficiency

Our best result was with one customer who, after 50,000 on his BSA A10, still had 2 and a half thou or less clearances valve to guide. Less than they would have been when they left the factory. Standard replacement such as those Norman Hyde sells, guides run at clearances of 2 to 3 thou. Same as the the tolerances on the new 1999 model Harley-Davidson and others. The standards of early original factory parts can sometimes even be as bad as the parts they are replacing, so it is worth checking that your parts supplier knows what they are selling you.
 
 

• More Performance

At low to mid range cam lift there is a huge vacuum in the inlet port as the engine tries to pull the volume of mixture in the inlet port through a tiny gap between valve and seat, a flow that is improved by a 3 or 5 angle cut. On high revving modern engines, 10,000rpm or more, this is also true of the exhaust port where exhaust gases are escaping along the pipe draw by the gases of the last stroke. 

The engine under these circumstances is trying to draw air from any available source, including down the side of guide with its inevitable oil mist included. Narrowing the gap reduces this and requires the engine to take gases from where it should be taking them; through the carburettor or out of the chamber. 

To avoid petrol wash, where too much petrol is drawn through the engine washing away all the lubricant and causing premature wear, it is necessary to lean out the mixture by always reducing the slide size and sometimes the needle jet.
 

Unmatched Durability With K-Line Guide-Liners fitted, matched to quality new or refaced valves and freshly cut seats, we guarantee owners to return 2 to 3 times the mileage one would expect. One racing head we set up, a championship leader, did 3 seasons without need a head job and still was still in better shape that it would have been straight from the factory at the end of it season. Nothing more than a light lapping with Solvol Autosol was necessary to send it out for its fourth year racing. More recent tests have shown that K-Line's Bronze-Bullet Interrupted Spiral phosphor-bronze Guide-Liners exhibited 41% less wear than smooth wall liners, as used by other tuning shops, under harsh durability testing environments even at similar tolerances. K-Line manufacture and stock the only complete selection of Guide-Liners and Guide-Liner installation tooling in the World. Due to our many years of successful adoption of this technology, any problems in wear following the fitment of K-Liners or Nucleus Sports Elite Valves can be traced to the lack of carburettor adjustment. The penultimate combination would be to have Nucleus Power Guides fitted with K-Line Guide-Liners. Bespoke fit, incredible heat transfer and many other individual benefits for differing models.