Was this done by rotating the gear on the exhaust cam like to mentioned to me at the Nationals this past June. I can't remember the full details, but it would be nice if when you get all of your testing done if you'd do a seperate wright-up (How To) just on the cam change and how the change affects the power curve, as this is something that I think I'd like to do.
Yes, that was me. It will really be impossible to quantify that as a sole mod, since the exhaust was done at the same time.
I have sold hundreds of
advanced exhaust cam sprockets for the c-10, and guys love them because it's a definite boost in low rpm for not much money. By retarding the exhaust on the c-14, I was just looking to bias a bit more toward the top end. My rationale is that the once the flies are pulled (it's an 09) the bottom end torque ought to be all I need, so why not bump the top a bit. At this point, til we see dyno numbers, it's all just academic.
One note on dyno tuning - my c-10 has had dozens of dyno runs. You must understand that unless you can do runs back to back, on the same day on the same dyno, then you are really looking for averages in improvement. All dyno's are a bit different, weather affects the results (even though there's provisions to take that into account) and how the bike is set upon the dyno, tire pressure, oil viscosity, all effect the results. a couple hp here or there becomes almost inconsequential; and then you always must consider not just peak HP, but
all that is developed under the curve. BTW, here's some c-14 cam timing info to help the tuners....
ZG1400 cams
INTAKE @ 050" valve lift, .006" clearance
OP - 10*atdc
Clo - 50*abdc
LC - 120* Static; I expect it advances to 100"LC
LIFT- .320"
DUR - 220* @ .050"
EXHAUST @ .050" valve lift, .008" clearance
OP 29* bbdc
Clo - 1* btdc
LC - 105*
LIFT - .300"
DUR - 208* @ .050"
EX w / 5* retard timing
OP-24*bbdc
Clo - 4* atdc
ZX1400 EXHAUST CAM (2007 model)
OP - 36*bbdc
CLO - 10* atdc
LIFT - .330"
LC - 103
DUR - .226* @ .050"
As you can see, the zx cam has 18* more duration, but it keeps the low LC to try to help low rpm power in the zx14 application. Keep in mind the zx intake cam is also long and has no VVT, so there's much more overlap for top end with the zx cams. If you'll notice, the c-14 cam shows no overlap, even with the EX cam retard, though I'm sure there's effective overlap flow going on at much smaller valve opening than the measured .050". This would be at very low rpm and idle, with a 100* LC on the VVT advanced intake and 5" retarded exhaust, the overlap would be 14* @ .050" lift, whereas in stock form it would be 9* @ .050"
HTH, steve