Harley- Davidson® spells hundreds of dollars for your shop

Harley®
Davidson
spells
hundreds
of dollars
for your shop
BY JOE MONDELLO
This article covers the proper way to port
and polish Evo and Twin Cam 1998 to
present cylinder heads with or without
valve guides in place. My way to do a
great valve job and maintain the 89%
throat dimension for intake and exhaust
ports will achieve the highest horsepower
and torque numbers in the country. I
will briefly touch on cams, but the most
important component of these Harleys
is the big bore kit with real, usable
compression ratios on today’s gasolines.
We will discuss how to bore and hone the
barrels to keep them straight and round.
Cryogenically freezing the heads,
pistons, rings, and barrels; then applying
high heat and lubricity coatings make for
a cooler running bike with no detonation
— even on the 10:1 and 11:1 for street
use. When using the higher ratio pistons
a compression release valve needs to be
installed in the cylinder heads.
On these hot summer days and nights,
grab a beer, sit back and read all about
it! The cost is really not much for porting
supplies; you might need to add a few
more carbide cutters, flapper paper, some
porting valve guide height gauges, and my
signature series Mondello 2010 porting
lube to your stock, but it’s well worth it.
The proper way to bore and hone with
correct torque plates will require a small
investment to do a good job. Coatings
and freezing you will have to farm out.
If you now use Neway 30, 45, and 60
degree angle cutters for performance use
50 JULY-SEPT 2010 engine professional
this will have to change. Use the multiple
angle seat cutters to obtain good flow
numbers and throttle response; get away
from that old school stuff. The old cutters
can be used on other jobs; they are better
than stones but once you use the 3D
system and multi-angle cutters you will
see what I mean. My signature series
cutter blades, distributed by Goodson,
are absolutely the best in the industry. We
prove this daily in all applications; our
numbers out-shine all those you find in
other magazine articles.
It’s not as easy as you might think.
You have to achieve good port designs
and shape, keep the 89% throat
dimensions, create good port and
combustion chamber finishes plus do a
multi-angle valve job, make the proper
cam choice, and most of all have a great
piston ring seal in your cylinders.
Now, after all this is said and done,
you must choose the best ignition system,
tuner and exhaust pipe. Then, after it’s
all buttoned up, you need to find an
expert individual to put your bike on a
chassis dyno and tune it with performance
upgrades!
I have built hundreds of sets of Harley
heads, together with big bore kits and
good cam choices, they have shipped all
over the world and guess what? There is
a difference of about 20-25 horsepower
and the same amount of torque from the
same combinations going to different
builders and tuners! All my parts,
heads, compression ratios, and cams are
equal but the difference is between the
individuals who assemble them. This
really blows me away so here are some
tips to keep the numbers high.
When porting your heads with the
guides in; drive the guide down from the
valve seat side about 1/2 inch. This will
allow you to have more room to port and
shape around the back side of the valve
guide boss. Partially shape the gussets on
each side of the guide boss towards the
port epening intake and exhaust. You will
finish shaping the front of the valve guide
bosses from the valve bowl side. Do not
remove material on the back side of the
intake or exhaust valve bowl area behind
the valve guide bosses.
When porting the valve bowls and
shaping the guide bosses, an 18-20 tooth
regular cut 1/2” diameter egg/oval carbide
cutter is the best to use unless you are a
good porter with much experience. If you
are very confident, use an 8 tooth fast
mill cutter like I do to rough in your ports
much quicker. I like to shape the intake
port and port mouth, shaping the “D”
port with an 18-20 tooth regular cut 1/2”
flame carbide cutter. If any ridges, high or
low spots appear where the port blends
into the valve bowl and guide boss area,
use the 1/2” egg/oval to blend.
Always try to keep your cutters as flat
to the surface you are porting as possible.
This applies to all carbide cutters,
cartridge rolls, flapper paper and cross
buff pads, too.
Exhaust D port layout ring.
Exhaust D port finish ported shape.
Pre-shaping guide boss.
Removing bumps in exhaust port wall.
Shaping exhaust valve guide boss.
Removed bump in exhaust port wall.
Forming exhaust guide boss guide in.
Forming intake guide boss of gusset.
Intake guide boss slug showing amount
of boss to be removed.
Porting plug in guide boss
up against spring seat.
Porting plug above spring seat.
Combustion chamber ported, polished
and cross buffed.
Intake guide boss guide out
totally shaped and finished.
Intake boss roughed-in and shaped.
Beginning shape of intake guide boss
being raised.
engine professional JULY-SEPT 2010 51
HARLEY-DAVIDSON®
BY JOE MONDELLO
Always use a good porting lube like
my 2010 on all items listed above. A very
light mist of the lube is all that is needed.
When porting your heads with the
valve guide in, totally finish all porting
operations before you drive the valve
guides back into their stock height.
While doing the valve bowl porting be
sure you do not exceed the 89% throat
demention. Usually all Evo, Twin Cam,
and V-Rod heads are smaller than 89%
so be sure you do not open up the throat
dimension with an 86° or 90° straight
blade cutter while doing your finish valve
job. We hand grind and finish our throat
dimensions to 89% of the valve size with
a 24 tooth 1/2 regular or double cut
round nose tree or egg/oval carbide cutter.
Again, be sure to use a good porting lube
like my 2010.
When porting heads without the valve
guides in you should use our porting
plugs; inserted from the spring seat side
of the head into the valve guide hole
(HDP4 set of 4 - .500, .600, .700, .800);
to determine the height of the roof of the
intake and exhaust ports. You should
shorten the valve guide boss at a slight
angle towards the back wall of the intake
or exhaust valve bowl; grind the boss
down until you can touch the front edge
of the plug making sure you have the plug
tightly pushed manually up against the
spring seat. We use the plugs to maintain
a correct height in the runner. I like to
use .600 on the intake and .700 for the
exhaust. I use an egg carbide to shorten
the valve guide bosses and re-form the
gussets next to them. Shape a small fin
going out towards the intake port mouth
but do not make it sharp; leave it gently
rounded. In the exhaust side, after you
shorten the guide boss and for the gusset,
use a rounded shape towards the exhaust
mouth opening. Egg and flame shaped
carbides work best for this.
On early Evo and Twin cam heads
(1998-2004) make a “D” shaped exhaust
port. They make more power and torque.
We have a layout flange available which
you can use to grind the perfect shaped
“D” port (item #DP-TC). Put the flange in
the exhaust port and rotate it until the flat
portion of the “D” is at the same angle as
the exhaust valve seat on the floor of the
exhaust port.
In the 1998-2004, there is a large
bump on the exhaust port wall. Totally
remove it and straighten that wall back
into the valve bowl area. I supply the
intake layout rings for most Evo and Twin
cam heads.
Next, you must re-shape the short side
radius. I have designed a special carbide
cutter just for this porting procedure. It
is a reverse teardrop shaped like an ice
52 JULY-SEPT 2010 engine professional
cream cone (RT series) which comes in
7/16 and 1/2 diameter recommended in
22 tooth regular cut for this project. You
don’t want an aggressive cutter in this
area. If you are going to flow test just roll
the short side radius from the bottom of
the seat into the floor of the port with a
smooth, rounded shape. If you need more
top end air flow then lay back the short
side radius making it flatter to the floor.
Be very careful here because you can ruin
a good set of heads by removing too much
material from the short side radius.
These are the
porting tools
you will need
for this project.
As you complete these rough-in
procedures remember the smoother the
porting job the easier the polishing is!
After I rough-in my ports using the finer
18-20 tooth regular cut carbide with
2010 porting lube I start my polishing
operation with a 1/2 x 1-1/2 x 1/8 60 grit
straight full round cartridge roll using
jporting lube to clean up and blend any
imperfections left from the carbiding.
Sometimes you may have to use a 1/4 or
3/8 diameter roll to get behind the valve
guide bosses.
Once you are through smoothing
with the roll, use the flapper paper stick.
I finish the intake ports at 80 grit for a
carburator and go to 120 grit for fuel
injection. When you roll up the flapper
paper, use a 6 inch strip with the end flush
with the slot and roll it clockwise; away
from you holding it tight while turning
it into an ice cream cone shape spiral.
Adjust the grinder air speed so you can
nearly stop the flapper stick with your
fingers. If the paper is bouncing, it is not
wound round or tight enough; if it is
shredding or flying apart the grinder speed
is too high.
If I’m going to use high temp non stick
coating on the exhaust ports I finish them
with 80 grit flapper paper. Otherwise, I go
to a high finish using in 80,120,150,180
grit then use medium and ultra fine
crossbuffs. Again, all abrasives should be
used with porting lube.
Your next step is to install new valve
guides. I recommend AV&V bronze.
Always measure your guideholes after the
guides have been removed. Do not order
in .001 over assuming the stock guides
were indeed .5625. I have seen some
Harley heads from the factory that had
smaller than stock guides in. Always mic
the guide holes.
When installing the guides, heat
the heads from the valve cover side
to between 150-175° then freeze the
guides in home freezer two hours or use
Minnesota Fast Freeze from Goodson.
Use an AV&V carbide reamer or
diamond hone for proper valve guide
clearance of .0012 - .0014 intake and
exhaust with chromed stem stainless steel
valves. When using high speed or nickel
plated reamers, material flow back will
occur leaving an inaccurate sized hole. A
Sunnen “Hone-All” valve guide tool will
also work but I recommend breaking the
edge at both ends of the stone into a taper.
Now you are ready to finish honing
your valve guides. Start on the valve job. I
like to use a 1.900 intake valve for 88 CI
engines and 1.940 on 95-107 CI engines.
The 1.575 stock exhaust valve makes
the best power and torque with 1.900 or
1.940. Many think if you install a 1.940
intake valve you must replace the seat —
no, you don’t. On this performance set of
heads do not use the Neway valve system
because the angles are not right, nor
are the widths of the cuts. I recommend
the use of my Harley-Davidson cutters,
available through us or Goodson, using
a 3-D system or DMC, Serdi, Sunnen,
Kwik-Way, etc. Doing the valve job
correctly will give you 15-20 cfm more
flow on intake and exhaust plus higher
velocity than any others.
Use IFT4539B-HP intake seat cutter,
then use the IFT1556HD to top cut
the ridge in the chamber that is left
by IFT4539B-HP cutter. Intake seat
angles are 45° primary cut, 39° top
cut, 60° bottom cut. Below 45° this cut
width should be .080 - .100 wide, top
chamber cut blending in 39° top cut use
IFT1556HD radius cutter. Just use the
edge of radius to blend into chamber
floor. Blend in the 89° below 60° bottom
cut to finish off. Exhaust seat angles 45°
primary cut, 39° top cut, bottom cut
full radius. This will have a ridge at the
bottom of the radius and will have to be
blended to your 89%. Use the same radius
top cutters as the intake to blend into the
chamber floor.
Remember, when doing the valve
job you must know what the camshaft
overlap is so the valves won’t hit each
other. For 98% of our head jobs we use a
2.030 stem height for intake and exhaust.
This is the valve tip height measure from
the spring seat to the top of the valve.
Always port your heads and do the valve
jobs in pairs as it is easier to match guide
boss uniformity, D port shapes, and the
short side radii to each other.
I do not want you to port the
combustion chambers; only blend and
polish them. If the chambers are black
power coated, use a 60 grit cartridge roll
or bead blast to remove coating. After
the valve job is finished, make some
chamber valves to cover the 45° seat
angle. Use an 80 grit cartridge roll to
blend the top cut angles into the chamber
floor and sides. After blending, use 120
grit flapper paper, then 150, and 180 grit.
After flapper sticking, use a medium,
then a fine cross buff to final finish. Do
not enlarge the chamber, just clean it up.
Always CC the chambers as most
aftermarket pistons are made for 84
CC chamber volumes. If you are going
to coat the chambers use just an 80 grit
flapper for your final finish.
Let’s talk a bit about cams and
compression. Most pick a cam that
is too large for the CI displacement,
compression, and total weight of the bike
and passengers. I like cams for unported
heads to be .500 - .540 lift; .220° - .240°
duration at .053 between 106 - 112 lobe
center line 88 - 95 inches up to 10:1
compression. With ported heads of 9.5:1
- 11:1 compression I recommend gear
drive and chain drive conversions 226° –
260° at .053, .510 to .600 lift; 100 – 106
center lines.
My choice of cams is Wood
Performance and Andrews Products.
Compression ratios with 10+ to 11.5:1
compression release valves should be
installed. Cermet combustion chamber
and piston top coatings with molyedium
disulfate coated piston skirts plus coating
the intake and exhaust valves and
exhaust ports is a great power and torque
enhansement; especially with todays
junk gasolines to eliminate pinging and
detonation.
I left the boring and honing for last
because if you could see how a lot of
shops do their boring and honing…well,
you wouldn’t believe what they do to
your barrels! I have spoken to many of
these guys and they really think they are
state of the art mechanics and machinists
— HA! Many (even the Harley factory),
now and years ago, use steel torque
plates to final hone the barrels then bolt
Layout ring to scribe intake port opening.
Joe porting Harley heads
using SD-400 Vises.
Showing bump in exhaust port wall.
Intake valve bowl with guide in.
Intake valve bowl with first shape
of valve guide boss.
Shaping the short side radius
with RT-series cutter.
Layout of D shape exhaust port.
Finished short side radius intake port.
Harley head on a Mondello
wet flow bench.
Four Harley torque plates on a
Sunnen RMC V30 machine.
engine professional JULY-SEPT 2010 53
HARLEY-DAVIDSON®
BY JOE MONDELLO
an aluminum head to it. Let me tell you
— steel and aluminum don’t have the
same clamping force so the barrel distorts
and now the ring seal is no longer good.
Even aftermarket torque plate honing
kits come with steel torque plates top and
bottom and they supply grade 6-8 bolts
for you to bolt everything together.
Many of you are pretty sharp, I know;
I’ve spoken with you, so you know
where I’m going with this! You cannot
bore barrels on a lathe and keep the
concentricity true because you only have
support on one end. You cannot use the
above described torque plates and bolts
for a good honing job — clamp it in a big
vise, grab a Sunnen, Lisle or Ammco hand
hone with a medium grit then a fine stone
using motor oil thinned with cleaning
solvent or Kerocene and expect this hole
to be round or straight!! Come on, you
can’t control the stroke and cross hatch or
the heat generated from this process and
the finish for a good quality piston and
ring combination to seat properly.
At Mondello Tech Center, we make
our own torque plates from basically
the same aluminum density thickness for
54 JULY-SEPT 2010 engine professional
both top and bottom plates; use the same
bolts and fasteners, and the same head
gasket thickness and material content as
at final assembly. We freeze all barrels
before boring and honing. Four barrels
are installed in our precision torque
plates using the correct studs and head
gaskets torqued to factory specs and put
in our 70° constant temp final assembly
room a minumum of six hours before
we put them in the computerized V-30
Sunnen RMC for boring and correcting
concentricity.
After they are bored to within .005
of finished bore size and the same
fixture is bolted into our Sunnen SV-10
computerized honing machine, we rough
hone with diamonds to within .0025 and
finish hone with stones for final ring seal.
The final procedure is using 220 grit
to size 3 strokes of 280 and 3 strokes of
400 light to med pressure. The resulting
barrels are very straight and round and
will run many thousands of miles for
you with good ring seal as we use plasma
molyductile ring sets. We use MLS head
gaskets for all the big bore kits as they are
the best!
I hope this has helped you find a new
niche in this modern world of hard times
and this has bettered your ability to make
more power and torque to make more
money and build your base of satisfied
customers. My custom torque plates are
available, just phone me with your custom
order.■
Joe Mondello has been involved in quality head porting
and R&D at a time when Ed Iskenderian, and a few
others started a high performance industry. Joe has
been so successful that his tech manual was given
a GM part number. Joe is an innovator and educator
of the highest order. When he could have sat on his
laurels, Joe chose instead to start a Tech Center in
Crossville, Tennessee holding classes for any who
desire to learn air flow secrets that took Joe a lifetime
to find out. You may contact Joe at 931-459-2760 or
email [email protected].