Chevrolet Small Block Rollerized Thrust Button

†Item shown in picture may not represent exact product .

Thrust buttons, also called cam buttons or thrust plugs, keep a roller camshaft from walking in the engine. They are a crucial part when retrofitting certain factory non-roller engines with a roller cam. In flat-tappet engines, the cam lobe taper that causes the lifters to spin also counteracts the forward thrust caused by the distributor drive gear. Roller cam lobes have no taper, resulting in excessive 'cam walk.' Some engines are factory equipped with a camshaft retention plate to keep the cam in place, but those that aren't require a thrust button to keep the cam in place. The 'head' end is inserted into the center hole of the cam sprocket and the 'tail' end thrusts against the timing cover, keeping the cam in place.

Rollerized thrust buttons have a series of miniature Torrington bearings that allow the head of the plug to spin independently of the body, greatly reducing friction and timing cover wear.

DETAILS
Make: Chevrolet
Engine: Gen I Small Block V8 w/o OE hyd roller cam & 4.3L 90V6 w/o OE hyd roller cam
Style: Rollerized
Material: Heat-treated Steel
Length: 0.690" (p/n 7187-S) or 0.850" (p/n 7187)
Head O.D.: 0.875"
Body O.D.: 0.700"
Notes: Center hole of the cam sprocket must be at least 0.875". Your sprocket may require the hole to be enlarged.
            0.850" long button is designed to be used with pre-1978 style timing covers. Always check for proper clearances & endplay before final assembly.

**If you have any questions in regards to the compatibility with your set-up please call before you purchase**