When it comes to the LS engine family, one thing there is no denying is that GM developed what might be the best OEM slider-tip rocker system, ever. We’ve seen (and used) OEM and OEM-style rocker arms in a lot of LS applications over the years. However, that’s not to say they are perfect. Far from it, in fact. Especially when we’re maximizing every component of the engine. Enter Howards Cams and its billet-aluminum roller-rocker arm kit for the LS family of engines.
For over 70 years, Howards Cams has been building cams and valvetrain components for high-performance engines. So it only stands to reason that the team’s experience eschewed the “good enough” mantra that surrounds the OEM-style LS slider-tip rocker arms and decided to go the more traditional route, developing a full-roller rocker arm for LS applications. If you’re a small-block Chevrolet fan, these rocker arms appear to have a host of differences over stock. You might notice some similarities if you’re a fan of other brands (*cough* the Blue Oval *cough*).
Body Of Strength
When discussing valvetrain components, the age-old conundrum is balancing the weight of the rocker arms with stiffness. Since the rocker arms have to move back and forth several thousand times per minute, coming to a complete stop at each end of its travel, weight is important (inertia and all). However, resisting the urge to bend when there are forces being applied at either end of the rocker arm, simultaneously, is also a critical design feature.
In order to balance both weight and stiffness, Howards has designed a rocker body out of billet aluminum, which is anodized in the company’s signature purple color after heat treatment. ““Howards Rocker arm bodies are made from 7000-series aerospace grade aluminum for maximum strength and minimum weight,” says Howards’ Eric Bolander. The aluminum rocker body offers ample stiffness, and reduced weight is one of aluminum’s inherent physical properties.
Because the Howards engineers are in complete control of the rocker arm design, they are able to produce the rocker arm bodies in both the factory 1.7:1 ratio, and an upgraded 1.8:1 ratio, for a little extra lift and duration from a given cam design. Additionally, the rocker bodies are designed to install with no special modifications to the cylinder heads and work with most standard valve covers. “Howards Rocker arm bodies are 100-percent CNC ground to factor out human error,” shares Bolander
However, aluminum is inherently less wear-resistant than steel, so a pushrod, hardened or not, rubbing in the pushrod tip pocket would quickly wear into the aluminum body. So Howards fit the tip pocket with a hardened steel wear cup for the pushrod tip to ride on. On the other end of the rocker, a hardened steel roller wheel and axle shaft are fitted into the aluminum rocker body. The roller tip’s axle is fitted with needle bearings, which allows for much less friction across the face of the valve stem, especially compared to a slider tip design.
Enhancing The Fulcrum Of The Roller Rocker Arms
One potential source of consternation for all rocker arms is the fulcrum point. It has a big job in the overall scheme of things, not only having to support valvetrain loads, but also to rock back and forth, smoothly and reliably under those loads. That is no small ask. In order to both carry the loads of a higher spring rate and higher RPM, Howards has opted for a needle roller bearing setup surrounding a hardened-steel trunnion shaft.
Like the OEM rocker arm design, the Howards rocker arms use a fixed pedestal mount as opposed to a stud mount with a polylock nut, like a lot of aftermarket rocker arms before it. However, unlike the OEM pedestal mounts, the Howards rocker arms use a pedestal mount that you might be very familiar with if you have ever messed with late-model 5.0-liter small-block Fords.
Instead of the factory LS pedestal mount that spans the entire cylinder head, each rocker arm uses an individual cylindrical pedestal mount that sits in a siamesed tray at the base of the pedestal to prevent rotation. The rockers bolt down with the factory rocker bolts, at the factory 22 lb-ft of torque. Like the factory arms, there is no adjustability, but there is also no need for adjustability, as the Howards rocker arms are designed to work with all of the stock LS valvetrain components while being able to handle upgraded spring pressure and aggressive cam profiles as well.
Howards Cams’ rocker arms are made in the USA and have a lifetime warranty to the original purchaser. All of these features add up to a stout rocker arm upgrade for LS-based engines. Just because the stock rocker arms on LS engines are good, doesn’t mean there isn’t room for improvement, as these billet aluminum rocker arms show.