521 Chain Drive Cam.
521 CAM - Aggressive pulling power with a nasty sound, the REAPER 521 grind will shine in 114 and larger cubic inch engines with added compression ratio. Ported cylinder heads are not required but will complement the cam and add even more pulling power throughout the range. The stock throttle body produces an excellent powerband and use of a high flow throttle body will increase peak power numbers. A high flow exhaust system and air cleaner is highly recommended for optimal performance. FEULING recommends matching this cam with our RACE SERIES oiling system.

NOTE: High Lift valve springs are required on stock cylinder heads, see FEULING BEEHIVE valve spring kit #1107 (DRAG# 0926-2973) or #1108 (DRAG# 0926-2974). SE cylinder heads have high lift valvesprings and will accept the 508 and 521 grind cam. Heavy Duty one piece pushrods are also highly recommended see #4087.




Valve Lift Open Close Duration @ 50 lift @ TDC Lobe Centerline
Intake .518 17 BTDC 34 ABDC 231 .162 98.5
Exhaust .521 51.5 BBDC 11.5 ATDC 243 .125 110
Overlap: 28.5

*Cam specs measured in the engine on the lifter @ 0.050 using a 1.61 rocker arm ratio

Feuling does not recommend tuning beyond stock emissions standards.


FITS:
Milwaukee Eight 17 - 21, 521 grind chain drive cam, 518 Intake lift, 521 Exhaust lift, high lift valve springs required, performance pushrods and lifters recommended. RPM 2,250-6,250