Dyno Tuning and ZX-14 Throttle Body

[Steve in Sunny Fla]

 In the interest of actually learning something rather than accepting the internet gossip, I've modified a 2005 zx12 header onto my c-14. I did this for several reasons, but basically to use the same diameter pipes w/o cats to actually see if there will be a difference as compared to the stock header with cats. the header is on and fits perfectly, I've just picked up an autotune for the PC so I need to get that installed, tune, and then go to the dyno.

That said, I fully disagree that the gains made by just doing aftermarket headers and exhaust is modest. When comparing power in terms of percentage gain, I really think the c-14 responds much more than many other bikes to exhaust work. again, I do suspect the cats, but I could be wrong, so only data will solve the problem.

 BTW, the zx12 made 160+ HP in stock form at 10k. When the rest of the exhaust system is disected it's really obstructed and odd - cyl pairs are kept separated until the muffler, which had a cat in it. I did away with all that and the header comes to a 2" collector then out a 2 bros midpipe / muffler.

 I've also dialed in the cam lc's and actually retarded the exhaust 5 degrees for a bit more overlap which will equate to more top end. I have zx14 cams and considered installing the exhaust, but I figured I needed to see what moving the stocker would do first. Really, there's nothing to be done with the intake cam, just sit back and let the vvt do it's thing. One interesting thing about the exhaust timing retard is that it quiets the exhaust tone, which I like. Steve

[The Pope]

I've also dialed in the cam lc's and actually retarded the exhaust 5 degrees for a bit more overlap which will equate to more top end. I have zx14 cams and considered installing the exhaust, but I figured I needed to see what moving the stocker would do first. .......... One interesting thing about the exhaust timing retard is that it quiets the exhaust tone, which I like. Steve

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.

[Steve in Sunny Fla]

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

   

[The Pope]

So if someone used the zx14 exhaust cam and retarded it 5*

   ZX1400 EXHAUST CAM  (2007 model)
   OP - 36*bbdc
   CLO - 10* atdc

  ZX1400 w / 5* retard timing
   OP- 31*bbdc
   Clo - 5* atdc

correct?

Also, IIRC, you said that the C14 exhaust cam gear already has the hole drilled in it to do this. Is that correct or did I mis-remember?

Thanks for the info and apoligies to the op for the mis-direction!!!!

[Steve in Sunny Fla]

no, it would close at 15* atdc, 

5* atdc would be a 5* advance.

remember that more overlap will vent some low rpm cylinder pressure, but will pull the intake charge better at high rpm. that's why the vvt advances as rpm increases.

  and yes, i used the other set of holes in the sprocket, intended tor the zx intake cam. steve