SCREAMIN' PRO RACING PARTS EAGLE® - Harley-Davidson

choosing a cam
GiVE iT A LiFT
There are a few basic questions you should ask yourself when selecting a
camshaft for your Twin Cam engine.
WHAT IS THe PrIMAry uSe OF THe MOTOrCyCLe? Are you looking
for a bump in low-end torque for your loaded touring bike, or are you seeking a
big boost in horsepower to push your lightweight bike to victory at the strip?
WHAT TyPe OF rIDInG DO yOu DO? Is your riding style relaxed or
aggressive? Do you spend a lot of time riding stoplight to stoplight, or do
you prefer a leisurely two-up ride on back roads and freeways?
WHAT OTHer MODIFICATIOnS HAVe Been MADe TO THe enGIne?
Have you installed a mild Stage I air cleaner and street-performance muffler
package, or have you gone all-out with big bore cylinders, high-compression
pistons and ported cylinder heads?
When building an engine to satisfy these performance objectives, the
relationship between horsepower and torque is one of the most significant
concepts to understand. Camshafts, cylinder heads and stroke length
determine where the torque and horsepower peaks occur. While hot cams,
higher-flowing cylinder heads and a free-flowing exhaust system will move
the peaks higher up the rPM band, conservative cams may feel stronger to a
street rider because the maximum torque occurs at lower rPM. The experts
at your Harley-Davidson ® dealer have the knowledge, skill and experience to
recommend the optimum cam specifications for your riding demands.
cam comParISon charT
TWIn cam 103 STocK VS. 103 WITh ScrEamIn’ EaglE ® aIr clEanEr, cam anD STrEET PErFormancE muFFlErS
100
90
80
Hp & TORquE (FT-Lb)
70
60
50
40
30
2 2.5 3 3.5 4 4.5 5 5.5 6 6.5 7
Rpm x 1000
Tq
Hp
Stock 103cI
SE 103cI with SE254E cam
SE 103cI with SE259E cam
SE 103cI with SE255 cam
SE 103cI with SE204 cam
cam KITS 81
TWIn CAM MODeLS