very interesting

[chayes627]

i came across this website and i found it very interesting. http://mototuneusa.com/think_fast_intake_porting.htm
i think i am going to try this

[400exrider707]

That porting has been the hot topic of conversation and heated debates for quite some time on here. I've never really heard of too many people who've used it, but I think it would be interesting. Let us know how you make out.

[daddio]

It doesn't work, and you shouldn't try it. ;-)

J/k.......... If you look at the evolution of the YFZ (and YZF) they started with "big" ports, and each "improvement in horsepower" has been a smaller, more velocity port design.

[chayes627]

o really i didnt know that i'm a little skeptical so i think i might try it on a second head i do want to do dyno runs to see the exact gains i would get.

[fmftrx300ex]

i agree with tht guy tht they flow equaly as well in reverse but then desing a cam tht is not leting ur intake valve open while ur piston is returning!!!! smaller ports i dont think its worth it iv ported things and bigger ports make bigger power
to a point. its not all size its port desing also

seems odd that making the ports smaller makes more HP. I think thats the only guy I have ever seen do that so what is eeryone else crazy and makes ports bigger to lower HP? I think the guy making the smaller ports is a little whack. Too big of a port will lose power but making them smaller than stock thats like choking the motor

[daddio]

It's all about velocity, and V.E. The faster the air is moving, the more you will get into your cyl.
Actually a lot of motor builders do this, but it's not too well known.

Look at NASCAR......... They tried to limit the size of the ports and intake to slow the cars down, and the motor builders found more HP with the "smaller" ports.