SKU: COM4601-1
UPC: 036584390336
MPN: 4601-1
The COMP CAMS 4601-1 is a 3/8" Hi-Tech poly lock built for high-rpm race valve trains where rocker arm adjustment has to stay put. It threads onto 3/8" rocker studs and holds the adjuster screw setting through repeated valve events, making it a fit for 3/8" Ultra Pro Magnum and Ultra Pro Magnum XD roller rocker arms. Engine builders running aggressive roller cam profiles reach for this style of lock when standard adjusting nuts back off under load. It's sold as a single piece, so you can match quantity to your cylinder count or replace a damaged unit without buying a full set.
A poly lock works on a two-piece principle: an outer nut threads down the stud to set rocker geometry, and an inner set screw drives down against the stud to lock that position. That design resists loosening far better than a single jam nut once spring pressures climb. COMP CAMS lists this Hi-Tech version as its top poly lock for high-end race builds. The 3/8" thread matches the larger stud size found on big-block applications and stud-mount roller rockers, while the Hi-Tech construction handles the clamp loads those setups generate. Because adjustment holds firm, you keep valve lash where you set it across a long run. If you're also sorting stud and nut hardware, our rocker arm nuts and stud nut kits cover the rest of the valve train.
Reach for the 4601-1 when you're assembling or refreshing a stud-mount roller rocker setup and want adjustment that survives the rpm. It suits circle track, drag, and other competition builds running 3/8" Ultra Pro Magnum rockers, and it works equally well as a one-off replacement during teardown and inspection. Verify your stud diameter before ordering, since this is a universal item sold without specific vehicle fitment. Pair it with the right adjusting hardware and you have a valve train that stays in spec. Browse the rest of our fasteners for studs, locknuts, and related engine hardware to round out the build.
It's designed for 3/8" Ultra Pro Magnum and Ultra Pro Magnum XD roller rocker arms that mount on 3/8" studs. Per COMP CAMS, this Hi-Tech version is their top poly lock for high-end race applications. Always confirm your rocker stud diameter is 3/8" before ordering.
A poly lock uses two pieces: an outer nut that sets rocker geometry and an inner set screw that drives down against the stud to lock that setting. That arrangement resists backing off under high spring pressure far better than a single jam nut, which keeps your valve lash where you set it.
This part number is a single poly lock. That lets you order the exact count your engine needs or replace one damaged unit without buying a full kit. If you want a multi-pack, we also stock poly locks in set quantities under our fasteners listings.
No. COMP CAMS lists the 4601-1 as a universal item without vehicle-specific fitment. Compatibility comes down to stud diameter and rocker type, so verify you're running 3/8" studs with compatible roller rockers before purchasing.
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