Okay if I keep my dual valve springs I will have 190 pounds of seat pressure. Thats sounds like a lot of work for the cam. On my stock head I can press the valves in with my hands, but I can barely move these dual springs putting all my weight on them... so I am guessing this will take away some low end torque and the only advantage to running them would be higher rev limits and thats where the added peak HP would come from.

FOR dailily driving, and especially if my bottom end is a low RPM stroker.. dual springs would hurt my setup. am I wrong?

 

If you are running these in a in any Honda motor, it is almost double the Pressure you need for even the most radical cams. That type of seat pressure will wear your valve train dramatically. For Radical NA cams you only need between 75-80 on the Seat and 220-230 at full lift. Drag race boosted applications vary but will usually see at least an addtional 30 pounds the intake side, depending on cam selection and boost.

 

its hard to tell what springs they are since they are installed in a f22a nonvtec head but they might be ferrea S10063

95 lbs @ 34mm
215 lbs @ 24mm

that would be a lot closer to what you suggest
is there any way to tell by looking at them what part # they are?

 

I don' think you'd so much lose torque becasue the cam has to work against more pressure....after all, whatever work the cam does to compress the spring, it gets it back when it decompresses. The losses come from the extra friction the springs make. Also, as has been said, wear will probably increase dramatically.

I don't know how big of a deal this extra friction and wear is, but I imagine its pretty big as manufacturers don't seem to like making them any stiffer than they have to. This is despite the mechanical safety benefits it would have. For example, I understand on a b16 you'll start floating valves at only a couple hundred rpms past redline.

 

heavier spring=more friction.. more friction=less power

 

so a better way to upgrade would just be lighter valve versus heavier spring.. I think i understand the decompression part but you still have the angle of the ramp on the cam making friction.

 

well no matter what you do with a bigger cam you will haev to run more spring pressure. no way arround it.. but the power you make will greatly out do the power loss..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by hemlockz &raquo;</TD></TR><TR><TD CLASS="quote">so a better way to upgrade would just be lighter valve versus heavier spring.. I think i understand the decompression part but you still have the angle of the ramp on the cam making friction.</TD></TR></TABLE>

Lighter valves would definately be better...but I don't know how much lighter it's possible to go.