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Today we're gonna talk about something that may be magic to some others might just
be the normal course of building a motor
but it's porting a cylinder head
you've already upgraded exhaust
carburetor maybe even a cam
now what you want to do is
get the most efficiency you
can
out of better flowing heads
this is a traditional
small block chevy, this has happened to be an aluminum one
and your
exhaust ports here in your intake are pretty much just sand cast as is
what we want to show you
it's how you can
port these heads
and polish them and what we have here is a cut away of the same cast-iron
small block chevy
and what we're going to do here is to eliminate the flash that's on here in the rough cast
and smooth the airflow what this will do is increase the offender will also get
here a little bit more linear path
coming down in there
Alright, what you have in front of you here
is the Eastwood cylinder head porting kit
comes with uh... an assortment of eighty grit
abrasive rolls you have your ah...
straight role here
which gets you into the floor in the ceiling and the sides of the port
a lot easier and then you have your taper
this will get you into some of the tighter areas in the radius
also what we include are
two four-inch mandels
and to six-inch mandels
Alright, what what to do is take the uh...
take the mystery out of porting
It's really not that difficult
and its benefits are far rewarding and measurable even a uh... very simple
porting job can give you anywhere from two to eleven c f_m_ increase
first thing you want to do
start with this is a big block chevy that we have here
this is the intake side
take your intake gasket
simply use a couple bolts here too
just temporarily hold it in place
and what we're going to do is scribe
the gasket area itself
around each point just take a carbide scribe
so what we have one here
we have a scribe line of areas of the metal we want to remove and one thing that you
want to do when you're porting is remembered
don't move too much metal
what you want to do is simply smooth
the casting area itself
bring the metal the opening out here to your gaskets
and then stay about a half inch
back from the valve seat
what we're going to do is start off with what's included in the kit is the six-inch role
here
so we can do to speed stuff especially if you are doing cast iron heads is
we have carbide birch you can purchase carbide bars in a 3 inch length and a 6 inch length
What these will do is just speed up the production time.
simply
start working
around
the port itself you don't wanna focus just in one area there 'cause what your going to
start doing is
really miss shaping the port itself
so continue around
continue to go deeper deeper inside of the port now again
you can't do a lot of damage if all you are doing is smoothing the metal and not
tried to reshape and remove a lot
but where you do want to watch
I'll simply flip this pig
over
the valve seats themselves
you want to stay back a half inch
what a lot of guys will do is get into the uh... full area here and start blending
which is fine you can do that
one thing they have to remembers
any minute material you're removing here is actually lowering the compression
ratio
so i'd like to do is just get a feel see if there's any heavy casting flash if
you do find area
simply blend him out but most importantly when you're on the side
this area right around here around the combustion chamber
this tends to be very shot from the machining operation on the heads here
so you want to do with the used roll is just
gently
break that edge
just take one pass around there what it'll do is eliminate any of those sharp
corners which actually add to preignition
they'll turn into
literally glow plugs with heat there
Aright, we're going to start supporting operation now we're going to start in the
combustion chamber area
like we said earlier you want to stay away from valve seat area here
What you do want to notice is it is a sharp bridge
about a half-inch maybe five eighths up
below the valve seat itself and this
just by nature of the casting
leaves a step or a sharp edge what we're going to do is
go in there with our role
and start blending
and smoothing that out again you don't have to remove a lot of metal what you want to
do here is just break any of those edges you want to have
nice laminer air flow through here
so what we're doing is just
gently start with the uh...
carbide bur again this is an accessory that you can buy through Eastwood and all it does is
speed up the process
and then uh... you'll see a switch back to
to between the tapered
and the regular
straight roles
through the operation
stop, check your work frequently
again you're looking for
continuous blending
not so much just heavy metal removal
what we're doing here is just going in with the
six-inch mandel on here and tapered roll
going to the bottom or what was called the floor
also the sides and then the roof
uh... we're doing is going in there now
smooth everything out removing any of the uh...
work we created with the bar
and the casting flash
what i like to do is
continue to go around as much as you can
in a circular pattern circular and spiral in there
what it does is keep you from
grinding into one area misshaping but also
haim and whether it's
factual or not it just tends to
especially on the intake here
give you their belief as years coming in is given a swirling effect
so you know some change in the roles pretty frequently
there's still about half left in these
Since I only have to take about about fifty steps to walk in the warehouse
those guys that they're great they'll distract management and I can get
these things free all day long
you know the main thing i'd like to do is
like we did a gasket matching on here
get that open up to your gasket make sure you get the right gasket around there
in proportion to uh...
whether you're putting on headers or the original cast iron manifolds
Alright, now that you got these things ported
and uh...
cleaned up
what you want to do is
actually lap your valves
and what this does is this seats
the valve based tube to the
valve seat itself
there's lapping compound
which you can see i have
on my finger and about itself
plug your valve in
and the nice thing to do is just take a sharpie at this point
and uh... you can mark the valve itself to the cylinder
this is the valve lapping tool this is what you guys are probably familiar with
uh... these are a dime a dozen at uh...
auto parts stores of it
but it's used to suction cup on the valve
and then you continually do this
and what you're doing the lapping compound its self is
is an abrasive and what it's doing is it's removing a minute amount of metal
But, this is tedious
and you got sixteen of these things to do
so another trick
on the valve stem side itself
you take a small cordless drill
carefully
chuck it onto the valve stem
attache from the inside
and what you want to do is rotate at very very slow speed
slowly
very slowly
lift up a little
and bring it down this is itself a little bring it down
very slowly, you don't have to do that
for a very long period of time at all
and also another note is
with oil
on the valve stem itself so that you aren't wearing your guide
remove the valve wipe off your lapping compound
and if you have a good
valve to valve seal
what you'll see is a band right around the middle of the valve
face area itself
Alright, now that you did all those valves
now the thing to do since you got the heads off
Go ahead, you made them flow nice you might as well
make 'em look nice
this is our new high temp
ceramic engine paint
we sell this in quarts it's set up right out of the can it can be sprayed through a spray gun or it brushes very nice also
This is very nice
also
it's a one-inch foam brush
it wouldn't take very long to cover here
and paint the entire head
very easily