helixspecs

The Bolt-On gear cam VS the press-on gear cam is pictured to the right. This shows the difference in the two camshaft noses the gears press fit to. The top camshaft is the bolted-on gear style. The shorter nose and press fit area allows the cam to fit in the same space as the stock camshaft, even though there is a thick retainer and bolt used to hold the gear to the camshaft. The bolted system is a much stronger design and is indicated for use on P7100 pump engines, high performance VP44 engines using nitrous, sled pulling and drag racing.

Press fit cams are fine for just about all VP44 and CP3 Common Rail pump engines. Racers and pullers should consider a bolted system from an added stress standpoint. Nitrous? You need bolted-on.

The Bolt-On system is shown on the left. The mounting bolt travels through the camshaft to the second bearing journal. This serves a multi purpose: The first is to hold the gear securely to the cams nose and the other is to provide added rigidity to the cam billet itself. Cummins camshafts break most often in the area between the first and second bearing journal. The M12 fastener used is torqued right at 80 ft lbs for positive engagement. Click the picture for a larger version if desired.

Alloyed from Chromium Steel the Pro/SportsMan springs are designed to be used with the Helix 2 and Helix 3 camshafts. They control the valve train without any compromise. They fit in the stock location, use the stock retainers and locks and will not rip the stock valve seals up like a double spring will. They are triple shot peened, and special process hardened to proved a life long solution for the Cummins 24 Valve engine. RPM range is unlimited. Boost is unlimited. You will not float with these. The steel used is an ovate shaped wire, not round. This allows high lift cams to never coil bind and plenty of room to install even the most radical lift lobe camshafts.

Pictured here is a computer analysis of the ovate wire spring VS the round wire spring under load. The red and blue areas indicate the highest and lowest stressed area respectively. The ovate wire is clearly less stressed and the stress is not located inside the spring coils like the round wire is. This lower stress will increase spring life, durability and generate lower heat. The larger cross section in the ovate wire shows much more blue
( low stress ) areas as well.

            STOCK and Pro/SportsMan Spring Pressure Curves

                                       Stock                    Pro

Seat Pressure                   80 lbs                  93 lbs

.100" lift                          100 lbs                125 lbs
.200" lift                          120 lbs                157 lbs
.300" lift                          145 lbs                193 lbs
.325" lift                          150 lbs                200 lbs   Stock 24V Intake lift at the Valve
.395" lift                          175 lbs                225 lbs   Stock 24V Exhaust lift at the Valve
.400" lift                          179 lbs                230 lbs
.450" lift                        COIL BIND            245 lbs
.500" lift                        COIL BIND            255 lbs
.550" lift                        COIL BIND            265 lbs
.568" lift                        COIL BIND            270 lbs
.

After slipping the retainer onto the cam gear, the long bolt is the next step. The F1 Diesel cam gear retainer was manufactured from billet steel on a CNC machining center. This is an exclusive retainer design from F1 that allows the use of your stock cam gear. You no longer need to machine the gear for clearance or need to buy the expensive Cummins gear.

The TTY ( torque to yield ) bolt is almost completly installed. The required torque specification is 20 ft lbs, plus an additional 180 degree turn. It is best to apply the 180 degree turn after the cam is installed in the engine. This will allow you to use the engine to hold the cam in place to apply the Tq. without the cam turning.