Fritz Kayl, KATECH
"Designing Ultimate Performance LS Heads and a Review of the 500 Inch LS Build"
Fritz Kayl has been on the cutting edge of LS1s since the very beginning, as the Technical Director and C.E.O. of Katech. With a background in engine building that dates back to '60s drag racing and a stint at McLaren, Fritz parlayed that experience into establishing Katech in 1977 with Warren Frieze to satisfy the demand created by corporate race programs (IRL, Busch Grand National, ASA, Trans Am, IMSA GTO). Eventually Katech rose to LS fame with the wildly successful C5R program, and continues to build LS motors for competition and even for street-going cars with the relatively new performance division.
Katech is most proud of its latest endeavors, the first being a partnership with RHS to create the ultimate performance LS head. Using the L92/LS3 style intake runner, Katech hopes to equal or surpass the performance of LS7 heads. A few of the features include an 11-degree valve angle and 0.750-inch thick deck as well as optimized port volume and seat to port transition available in as cast and CNC versions. To create the ultimate LS head, Katech had to flow test all major heads on the market including both cathedral and square port designs. A few of the development techniques used by Katech include the creation of a "Flowbox," which is typical of OEMs, to allow a precise design that can be easily manufactured. Modified and welded ports and chambers allow the designer the ability to roll and relocate the valve guides, change shape, etc. Working on the flow bench they hope to achieve stability at high lift, tweak the chamber design for peak stability, adjust the valve job for mid-lift flow, and use the wing to aid peak lift flow numbers. Fritz says they are currently in the process of tooling, validation and finalization of the valve job will follow before you can get your greasy little hands on them.
Another project Katech has devoted much blood, sweat and tears to--the 500 cubic inch, 600hp emissions-compliant C6RS motor--has many LS enthusiasts foaming at the mouth. Utilizing the Dart billet aluminum block to minimize weight, a 4.205-inch bore x 4.500-inch stroke is enabled, and the large displacement allows for the huge performance gains without using a "dirtier" cam. Meanwhile, production LS7 heads and valvetrain as well as most of the covers and dry sump oiling system are utilized. The huge stroke required moving the camshaft up, a taller deck, and crankcase clearance. Welded water jackets, nickel chrome bore surface treatment (sometimes use sleeves), and priority main oiling are among many other features. Using the tall deck, billet block was not without its concerns or problems though; packaging (size), injector angle, crank journal overlap, cheek height on the rod journal, crank torsionals, oil control, ring stability and windage to name a few. Katech had to work with Cometic to develop a durable head gasket to match the unique 4.205-inch bore LS deck surface. Still in development and testing is a ring package and a compatible cylinder liner or coating to reduce oil consumption, though Fritz assures that they are close. Emissions testing and a 750+ horse (off road) Desert engine package are soon to follow.