-
Can I have my head ported and
still be legal in the stock class ?
Yes in AMA Sanctioned Events, No in NMA
Sanctioned events. For racers seeking NMA Stock Only Classes see our
Stock Class Limited Cut and Clean Package.
-
What are ports ? (yes ,we still get
this one a lot) Ports are the hollow
spaces within the head that are the pathways of fuel/air going in and
exhaust gasses coming out of the combustion chamber. The ports both intake
and exhaust are divided into two general areas called runners and bowls.
Runners lead to the bowls and the bowls lead to the valve seats.
-
Why does a ported head make more HP ?
Engines with ported heads produce more HP
because they flow with more efficiency, produce more vacuum at lower RPM,
and flow higher volumes at max RPM. Porting eliminates sources of turbulence
in the intake and exhaust tracks that can cause an erratic HP curve or an
undesirable power band curve.
-
Why don't motorcycle
manufactures port their heads ? It
takes too much time. The hand finishing of
ports inside a head is a very time consuming process and far exceeds the
time it takes for the manufacture to assemble the bike.
-
Why is cutting the valves important ?
Leaking valve seals are the number one
contributor to power loss.@ 100hrs run time .Out of spec valve lash and worn
seals can create the recipe for DISASTER, damaging engine parts and costing
thousands of dollars in repairs.
-
What is a flow bench report ?
A printed report with sets of graphs and charted velocity values from
testing on a flow bench. These are used to determine the efficiency of air
flow thru a port shape.
-
What is CCing a head ? CCing
a head is to check the volume of the combustion chamber for pre determined
target volume numbers or the matching of multiple cylinders heads to
identical volumes.
-
What is the best way to raise
my compression, mill the head or install a high compression piston ?
Both will work, but a high compression piston
will yield more performance due to it's improved squish band and greater
gain in compression ratios.
-
What is the difference between
turbulence and tumble ? Turbulence is
a circular back flow that restricts overall volume of flow. Tumble or edge
tumble as it is sometimes referred to, is the phenomena of a very thin layer
of continuous eddies that add to to volume of flow. example: a tooled finish
intake port will flow more fuel/air than the same port polished to a fine
finish is an example of the edge tumble effect .
-
More About 4 Stroke
Engine Theory & Maintenance.
We Make Getting
Your Head Ported and Valves cut Easy !!!
