Ever wonder what will set ported heads apart?

[Kenny]

This is the start!! It actually lifts the the valve .565" (.578' gross)vs the standard web 4 that is somewhere shy of .490". Problem is, it only fits my head This one probably won't see any use because the duration came out to 280 at .050" and when combined with that lift will make a 770 wanna run at about 11 grand (Troy)

[Troy]

Send it, I'm not scared 

[Kenny]

John would kill both of us! I'm gonna add about .040" to the lift and knock about 40° off the duration. We are gonna see great top end power gains, but I am actually a little worried about what the midrange torque gains are gonna do to clutches

[Troy]

If it's gonna destroy clutches I want one 

[Gunz]

Send me one pronto, with a head... so I can test it and keep it. If I put that on destroked 700 what would happen??

[Krandall]

You would die a quick and painless death most likely.

[VelociRaptor]

You want me to name this one too?
Clutch Killer?

That cam is so big its got its own cam!

[Kenny]

A little math on Troy's build shows that it would want a 9500- 11,500 RPM operating range, which is not as bad as I thought

Aaron's bike would be about the same with the smaller valves.......

There is a lot of powerband alignment issues that make me want to drop the duration and raise the lift. Some initial testing with a .625" lift cam has shown the nose shape and closing ramp to be more gentle on the valvetrain than some of the lower lift cams that are currently being run

[Troy]

Do work son, I need a cam in the next week or so

[Colorado700R]

GTFOML Troy


Nice work kenny, can't wait to see what it can do! 

[Krandall]

My mind is wandering now.....


So. reading more into this... Is it the lift or the duration that says where motor RPM's should/will be?.

I don't understand how lift will make it want to run faster. I would think that if you had the valves open longer (I'm assuming since they have to travel farther) that it would drop rpm

[SUB454]

Who's gonna make the spring's to support that?

[preddy08]

I'm guessing R&D 

[Kenny]

That's an easy one baby!! More duration is the main trick, you just have to put it in the right place. This cam has over 120° at .500" lift, and the WEB 4 has 0°. Obviously the head is flowing far more at .500 that it is at .050. Near 300 CFM more in my case. Adding extra duration vs lift is really bad for low end and midrange torque, and makes for a more peaky powerband.

Valve window area vs time vs port flow for a given head design is VERY complicated

[Kenny]

Who's gonna make the spring's to support that?

I'm guessing R&D 

We have a couple of options like PAC and Ferrea, but on this particular design, it looks like properly installed Kibblewhites are gonna do just fine