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Jim Miller has been involved in the racing industry for over 35 years. Like many company founders in America’s racing heritage, Jim’s roots stem from amateur racing, starting with motorcycles at 15 and cars at 16. At 17, Jim was the youngest Ford trained line mechanic authorized to do warranty work on all of Ford’s factory muscle cars, an impressive lineup that included: the BOSS 302, BOSS 351, BOSS 429, 428CJ and the 429SCJ, among others. After a year racing a 1967 Mustang GT, it was traded for a new 1970 BOSS 429 Mustang. Within a month it was disassembled to prep for B/MP, using the best parts from Holman-Moody, Gapp & Roush, Arias, Crane and other top companies. It marked the modest beginning of a long love affair with cylinder head and valve train development that would span from motorcycles to airplanes, and cover many V6 and V8s in between.

In 1972, after walking away from the 105 MPH end-over-end crash of his first BOSS 429, a second BOSS was bought a month later, which Jim took to the next level. Two summers of racing the first BOSS had proven to him that implementing cams and induction similar to the Chrysler Hemi, with radical port size and high lift, were the secret to this engine's awesome port flow capabilities. This was opposite the reduced port thinking of Jack Roush and other leading BOSS Pro Stock racers. RPMs were pushed to 8,700...and the small steel OEM intake rocker was lifting beyond its arcing range. Roller rocker arms became a primary development for the engine of the second BOSS Mustang. At the time, the only aluminum rockers available were made for Jack Roush by Loc Performance, which Jim deemed were too heavy for the most complex rocker geometry of any American OHV engine. After a complete study of nearly all of America’s most popular engines Jim designed his own, and addressed the questions other companies considered unimportant. By 1973 the formulas Jim developed to optimize radial motion became: MID-LIFT geometry.

In 1980, with a Patent Pending, and 5 years experience on his own engines through two generations of rocker designs for the BOSS 429 (Series II), Jim finally published a full page ad in a February issue of National Dragster, announcing the principles of MID-LIFT geometry to the racing industry and attracting the attention of many noteworthy companies, including TRW’s high performance valve division, who considered Jim’s observations critical to solving their ongoing plague of valve tip losses in NASCAR.

In 1982, Jim received the only US Patent ever issued for a “concept” of precision rocker arm geometry. The MID-LIFT” Patent (4,365,785) spelled out the maximum efficiency of perpendicular geometry.

In 1983, Jim had refined rocker arm “beam” design and side thrust loadings to what became the Series III BOSS 429 rocker arms. Early customers included World Champion Bob Glidden and Funny Car World record holders, the Jordon Brothers. These were the first to use Torrington needle Thrust bearings; "drip down" oiling; and first revealed in June, 1985 Pulling Power Magazine article called Fomoco Frenzy.

By 1987, Jim accepted a position at Lunati Cams, in Memphis, TN, on the pretense of new product development and marketing, when in fact it it was for much more, as explained in The Lunati Factor.

In 1989, three noted valve-train articles were published simultaneously in the June issue of Popular Hot Rodding Magazine: Setting Valve Lash, Cam Company Shopping Guide, and Cam Basics, respectively.

In October, 1992, Car Craft magazine published Chevrolet’s Race Shop illustrations specifically recommending MID-LIFT as the preferred method of rocker arm geometry; the first OEM to publicly endorse.

In July, 1993, Miller Engineering Inc (MEI) was founded, solely to address making professional level rocker arms with MID-LIFT geometry.

In November, 1994, Jim published the advanced geometry principles of rocker arm design in a Super Ford Magazine article, called Rockin' Geometry.

In January, 1996, Precision Valve Systems (PVS) was founded to use a combination of international sourcing and domestic assembly in bringing a more affordable, precision MID-LIFT rocker arm to the market that engine builders could sell, making a reasonable profit in doing so. The PVS product group combined German imported steel and offshore 7075-T6 aluminum for the final work done at the MEI facilities in Florida.

Between 1996 and 2000, Jim was awarded three new U.S. Patents; 5,560,265, 5,596,958 and 6,041,750.

March 8, 2000, a highly confidential mandate from Chrysler’s racing engineers on valve train design parameters was issued to their seven teams, led by Ray Everham, which stipulated that rocker arms for ALL teams debut in NASCAR for the 2000 season would only be MID-LIFT geometry.

October 2003, the MID-LIFT.com web site was launched with 90% of its content being technical information for engine builders, and the PVS PRO-STAND™ systems were debuted.

In July of 2008, Jim retired from manufacturing and consolidated the dissolved MEI and PVS into MPG.

March, 2016, MID-LIFT Advanced Rocker Arm Tech is published; available HERE, as well as Amazon and other major and specialty outlets.


The Standard By Which All Is Measured!™


Contact: Jim Miller

MID-LIFT™, PRO-SHAFT™ & PRO-STUD™ are JM Miller Trademarks; Copyright © MMIII~MMXXIII