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For many years the business model for the performance aftermarket was “build it, and they will come”. That was fine when racing was more homogenized and there was just a handful of engines and cylinder heads being used for competition. Deciding what needed to be built was fairly simple, and a manufacturer could be confident that he would sell enough parts to cover its tooling and development costs.

Racing today has become so segmented and specific that virtually everyone needs something different. Sure the masses are still well served with off-the-shelf components, but at the top, the game has changed to custom engine combinations. Just look at the huge number of new cylinder heads introduced each year. It became apparent to Jesel that its business model had to change to keep up with its customer’s needs and the changing market.

For several years Jesel has been putting in place the infrastructure to support its new business model, the Jesel Custom Shop. Digital surface mapping (Faro Arm), computer modeling software such as Solid Works and the latest Finite Element Analysis (FEA) software, rapid prototyping equipment and more than 35 CNC machines give Jesel the ability to design, prototype, test and build new valvetrain components in a very compressed time frame. Oh, and the secret weapon -- Dan Jesel’s 35-years-plus of valvetrain design and manufacturing experience. Dan’s experience spans all forms of racing – NASCAR, NHRA, Le Mans, Bonneville and more. The Jesel technical team is capable of going right to the final solution in a very cost-effective way.

The new Jesel Custom Shop business model is “ask, and we will build it.” And it seems to be working very well. In 2011 customers sent Jesel 126 different cylinder heads for which it designed and built shaft rocker systems. The Custom Shop designed more than 134 custom billet rocker stands, and more than 247 custom cam cores. Several new belt drives rolled out of the Custom Shop as well as thousands of steel rockers, many for Top Fuel and Funny Cars.

The latest generation of engines from Detroit hold great potential, however the GM LS and Chrysler Hemi are significantly handicapped by a lack of space for a proper high performance valvetrain. Most stock LS heads can only handle a 1.300”-diameter valvespring and short rockers that severely limit valve lift. The Jesel Custom Shop can modify your existing LS head to accept a 1.550” or larger spring that will accept valve lifts reaching 1”. By machining the head in house, Jesel can custom fit a longer pivot rocker to clear the spring while adding multiple mounting points to firmly secure the valvetrain. This modification also requires angle milling the valve cover surface and a set of Jesel’s billet aluminum LS valve covers to cover up the new Pro Series rocker system.

Another popular Custom Shop operation is milling big-block Chevy and Spread Port aftermarket heads for one-piece rocker hands. The standard kit has a single bolt holding the exhaust stands, and they have a tendency to rip out of the head resulting in costly repairs The one-piece stand fixes this problem and greatly stabilizes the valvetrain allowing more rpm and spring pressure.

So how do you get Jesel to take on your custom project? You can call Jesel at 732-901-1800 and ask for the Custom Shop or email the Custom Shop directly at: customshop@jesel.com. Either way, a Jesel consultant will interview you to gather the necessary information such as intended application, net valve lift, spring pressures, rpm range, and if power adders will be used. This information will be used to design a truly custom, one-off kit.

Custom projects are subject to engineering and programming fees. If it is a new product such as a rocker system for a new cylinder head, the customer will receive a plastic model and samples to approve before Jesel makes the finished parts.

In racing time is money. Even if you have the CNC machinery and personnel to build valvetrain components, can you really afford for them to experiment with such a critical part of the engine? Jesel instinctively knows how to deal with things like rocker thrust loads and pushrod-to-adjuster interface, and what metallurgy is required to build reliable, extreme performance components. It only makes sense that Jesel will get it done faster and more efficiently.


Steve Schmidt Racing Engines
Rick Watters Enterprises
Gray Motorsports
Patterson Racing
Moran Motorsports
John Force Racing
Stanfield Racing
Fulton Competition
Duttweller Performance
Garrett Racing Engines
Book Racing
Roush Racing
Schumacher Racing
Reher-Morrison Racing
Pat Musi Performance
JNR Racing
Buck Racing Engines
Bischoff Engine Service
KB Racing
Slawko Racing Heads
Joe Hornick Enterprises
Mast Motorsports
Alan Johnson Racing
Bullet Racing Cams
Morgan Lucas Top Fuel Racing
Forrester Racing Engines
Bob Kaiser Racing
Nickens Brothers Racing
Shaver Specialty Engineering
Hans Feustel Racing Engines
Cunningham Motorsports
Larry Morgan Racing
Jerico Performance Products
C & S Performance Engines
MBE Cylinder Heads
Sonny’s Automotive
DNE Motorsports
Jenkins Competition
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Cylinder Head 
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Maximum RPM 
Open Spring Pressure 
Net Valve Lift 
NA / Blower / Nitrous