I have a 2007 Ultra that I bought used in October 2007. It has a stage 2 kit in it. It was recommended that I install S&S 285G cams. I usually ride on long trips with 2 up so high end is not needed. Are these needed or are they the proper cams for low to mid range? I was just reading the 07's cam drives are good and I want reliability.
cams for my ultra
- Thread starter holmesr1
- Start date
Mattman4403
Junior Member
Seems like a lot of cam if what you want is middle and low
BUBBIE
Well-Known Member
I have SS570 gear drives in my dyna TC .....10.25/1 pistons...larger valved...42 mikuni.... FLOWED head work done...(hot rod)
THE 570 is ENOUGH cam in my built bike ... I could go to 585 but the duration of valves(more duration) would take away from the low-end torque I enjoy now....YOUR bike MIGHT get away with 570 SS but not my choice unless other work is done to cover the increased cam duration...
570= lift of valves=.070 of an inch (opens earlier and later close of valves)
585= lift of valves=.085 of an inch (opens MORE early and LATE closed)
SHIFTING the RPM band even HIGHER so MORE compression is needed to MAKE UP THE LOSS OF LOW_END TORQUE..
the LIFT helps the engine BREATH BETTER...... THE LONGER DURATION of the valves open and close moves the power-torque range usually to a higher RPM...HENCE: com'n up on the cam....
(you want YOUR power in the LOW RPM'S not HIGHER)
570/585 seams a little wasted on lower end torque....I noticed the 570 was good for all around performance on MY build......NOT knowing the intake and exhaust valve durations(open and close) on the 585 maybe compare it to the 570... UNLESS you have bumped up compression in your engine I would stay away from any cam but one that SAYS" LOW END TORQUE"(close to stock duration but MORE lift)
(you also NEED gear driven cams to ALLOW more lift***another subject)
Most people CAM OUT the low end torque just for the sake of having a BIG cam...... THE MOST power you can get is in the BUMP UP on compression....... THIS will BY IT'S SELF will give you LOW END TORQUE!
A LONGER duration cam will ROB the low end TORQUE at low RPM"S and ADDING higher compression will PUT IT BACK ...... SO WHERE IS THE GAIN?
BACK @ 2800 RPM!
FOR LOW END TORQUE,,,,I would bump the compression up a BIT ( 10/1 or 10.25/1 pistons or shaved heads) THEN go with a gear drive CAM with more lift AND not much change in duration.......
this will give you the low end torque you want. and a HOT ROD when you first twist the throttle!
JUST MY THINKING
signed....BUBBIE
THE 570 is ENOUGH cam in my built bike ... I could go to 585 but the duration of valves(more duration) would take away from the low-end torque I enjoy now....YOUR bike MIGHT get away with 570 SS but not my choice unless other work is done to cover the increased cam duration...
570= lift of valves=.070 of an inch (opens earlier and later close of valves)
585= lift of valves=.085 of an inch (opens MORE early and LATE closed)
SHIFTING the RPM band even HIGHER so MORE compression is needed to MAKE UP THE LOSS OF LOW_END TORQUE..
the LIFT helps the engine BREATH BETTER...... THE LONGER DURATION of the valves open and close moves the power-torque range usually to a higher RPM...HENCE: com'n up on the cam....
(you want YOUR power in the LOW RPM'S not HIGHER)
570/585 seams a little wasted on lower end torque....I noticed the 570 was good for all around performance on MY build......NOT knowing the intake and exhaust valve durations(open and close) on the 585 maybe compare it to the 570... UNLESS you have bumped up compression in your engine I would stay away from any cam but one that SAYS" LOW END TORQUE"(close to stock duration but MORE lift)
(you also NEED gear driven cams to ALLOW more lift***another subject)
Most people CAM OUT the low end torque just for the sake of having a BIG cam...... THE MOST power you can get is in the BUMP UP on compression....... THIS will BY IT'S SELF will give you LOW END TORQUE!
A LONGER duration cam will ROB the low end TORQUE at low RPM"S and ADDING higher compression will PUT IT BACK ...... SO WHERE IS THE GAIN?
BACK @ 2800 RPM!
FOR LOW END TORQUE,,,,I would bump the compression up a BIT ( 10/1 or 10.25/1 pistons or shaved heads) THEN go with a gear drive CAM with more lift AND not much change in duration.......
this will give you the low end torque you want. and a HOT ROD when you first twist the throttle!
JUST MY THINKING
signed....BUBBIE