Honda/Acura Specifically Designed and Modified Cylinder Heads
It's still early in the day, and it's only 80 degrees outside...
I know THIS can't last for long.... See the pictures, and read the story (Setting a Land Speed Record...):
The "Head Refresh" process is performed, along with a
Competition Multi-Angle valve job,
then re-assembly and vacuum testing.. (This is usually performed when valves do not seal, need replaced,
or at high mileage intervals, during ANY engine rebuild, or if ANY engine damage has occured)
[Read more details...]
$595
The "Head Refresh" process is performed, along with a
Competition Multi-Angle valve job,
then 30mm "pocket port" job, chamber buff, re-assembly and vacuum testing..
(This is a performance upgrade, allowing better overall power and torque)
[Read more details...] or Read H22 Pocket Porting article in HondaTuning Magazin
$950
The "Head Refresh" process is performed, along with a
Competition Multi-Angle valve job,
then FULL port and polish job, chamber buff, re-assembly and vacuum testing..
(This is a Street/Strip performance upgrade, allowing much better overall power and torque)
[Read more details...]
$1,150
The "Head Refresh" process is performed, along with a
Competition Multi-Angle valve job,
then FULL port and polish job, Modify and Polish Combustion Chambers,
CC Chambers and balance all four volumes plus/minus 0.4cc,
re-assembly and vacuum testing..
(This is a SERIOUS performance upgrade to overall power and torque)
[Read more details...]
$1,450
Full list of Performance enhancements, additional modifications, polishing, coating(s), Microlon metal
treatment, Chamber work, Surfacing, Camshaft and Cam Cap work, Throttle Body Modifications and Polishing,
Rocker Arm blueprinting, Oil pump modifications, Water Pump Modifications, Valve Spring work,
Racing Valve Guides and much more...
[Read more details...]
Select ANY picture to enlarge
Disassembly/Inspection
Detailed Inspection
Cleaning Parts
Remove Burrs
Check Valve Springs
Check Valve Guides
Check Valves
Measure Cam lobes
Measure bolts
Measure Retainers
Grind Valves
Lapping Surface
Microlon Treatment(s)
Clean Valve Trains
Guides Ready to Install
Springs Ready to Install
Dan at work, porting and polishing
Dan getting into his work...
Honda heads in Progress...
Finished head, ready to Assemble
DPR Racing's Famous World Speed Record Setting Honda/Acura Cylinder Heads!!!
Honda/Acura - Head Refresh Procedure
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- Pre-inspect cylinder heads; Check for completeness, and insure all parts are intact,
and have arrived without damage.
Disassemble head for inspection and cleaning(including stud removal):
- Failure analysis: Each component of the cylinder head; the casting for cracks, studs, bolts,
lifters, valves, springs, retainers, keepers, and seal(s) is inspected and gone over in great detail,
scrutinized, and then re-examined, to find every point of wear or damage. Inspect and clear every water
and oil passage, and the cam oil channels, bearing journals, and cam bearing journal surface quality.
We also look for "casting or core shift" which is a manufacturing defect effecting alignment of
EVERYTHING. Dowel pin damage(often from shipping), cap fit/alignment, rust, corrosion, warping/heat damage,
signs of seizing and/or lack of lubrication, galling/metal to metal transfer, and over all surface finish,
to determine if there is damage by weathering(junk yard cores), salt water corrosion(salvaged from flooded cars),
or by fluids such as brake fluid, coolant, or battery acid, some of which can render a core unusable.
Valve seats are checked for cracks, wear, settling, shifting, and "pounding".
- If applicable, Camshafts are checked for signs of wear, valve float, straightness,
lash, and checked to see if they run "true"(out of roundness).
- Check all mating surfaces for cracks and
straightness/flatness: The valve cover mating surface, and no warping or heat
damage of the head casting.
- Measure and record valve tip to base length: This measurment will determine valve
wear from "stretching" due to heavy or multiple valve springs.
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Clean Heads, Remove carbon, and clean valve train components
- Calculate valve guide
to stem tolerance and wear: This set of measurments is used to determine guide
wear, utilizing the stem of the valve to be re-installed as a basis.
- Inspect deck surface finish to verify flattness, straightness, check for
corrosion, scratches,
and damage or warping/cracking due to head gasket failure(s),
detonation, or rough handling.
- Inspect studs, and threaded holes for rust, wear, clearance and dirt, clean as
needed. "Chase" dirt from every threaded hole with thread chaser, "thread brush",
and compresssed air, inspect and clean each spark plug hole, threads, and
spark plug seating/mating surface, as well as the access bore, and spark plug
pipe.
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Inspect and test valve springs
- Inspect keepers and retainers under magnifier/light, measure retainer thickness,
and check inspect keeper grooves.
- Inspect heads and valve train for any signs of valve float, or
chamber damage from foriegn objects.
Lap, port faces and gasket areas for proper sealing.
Polish valve margins, Hand lap valves and re-inspect.
Clean for assembly.
Final Assembly, including new valve seals, is done in "clean room" environment.
Vacuum test, and sign off.
Pack and Ship.
Honda/Acura - Stage I Competition Multi-Angle Valve Job
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The "Head Refresh" process is performed, along with the following work:
Light debur
Lap, port faces and upper cap and gasket area for proper sealing.
Competition, high flow, multi angle, valve job
with preparatory angles.
Polish valve margins, Hand lap valves and re-inspect.
Set up proper seat pressure and clearances.
Final clean for assembly.
Preassembly inspection.
Final Assembly, including new valve seals, is done in "clean room" environment.
Vacuum test, and sign off.
Pack and Ship.
Honda/Acura - Stage II - Multi-Angle Valve Job/Pocket Port Job
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The "Head Refresh" process is performed, along with the following work:
Complete Debur.
Lap, port faces and upper cap and gasket area for proper sealing.
Port and polish intake and exhaust.
Gasket match, port 30mm into ports and pocket port under seats.
Light combustion chamber polish.
Competition, high flow, multi angle, valve job
with preparatory angles.
Polish valve margins, Hand lap valves and re-inspect.
Set up proper seat pressure and clearances.
Final clean for assembly.
Preassembly inspection.
Final Assembly, including new valve seals, is done in "clean room" environment.
Vacuum test, and sign off.
Pack and Ship.
Honda/Acura - Stage III - Competition Multi-Angle Valve Job, FULL Port & Polish Job
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The "Head Refresh" process is performed, along with the following work:
Complete Debur.
Lap, port faces and upper cap and gasket area for proper sealing.
Port and polish entire intake and exhaust.
Gasket match, and fully port intake and exhaust.
Lightly de-shroud combustion chamber polish.
CC Chamber and match all four volumes.
Competition, high flow, multi angle, valve job
with preparatory angles.
Back cut intake valves.
Polish valve margins, Hand lap valves and re-inspect.
Set up proper seat pressure and clearances.
Final clean for assembly.
Preassembly inspection.
Final Assembly, including new valve seals, is done in "clean room" environment.
Vacuum test, and sign off.
Pack and Ship.
Honda/Acura - Stage IV -
Competition Multi-Angle Valve Job, FULL Port & Polish Job and Combustion Chamber Mods
_______________________________________________________________________
The "Head Refresh" process is performed, along with the following work:
Complete Debur.
Lap, port faces and upper cap and gasket area for proper sealing.
De-flashed inside and out.
Modify oil returns for better flow and distribution.
Competition FULL Port and Polish, Intake and Exhaust. Gasket match or any intake/exhaust design fully port.
Radius exhaust seats.
De-shroud combustion chamber polish.
CC Chamber and match all four volumes within .4 cc.
Competition, high flow, multi angle, valve job
with preparatory angles.
Back cut intake valves.
Polish valve margins, Hand lap valves and re-inspect.
Set up proper seat pressure and clearances.
Blue print with documentation.
Final clean for assembly.
Preassembly inspection.
Final Assembly, including new valve seals, is done in "clean room" environment.
Vacuum test, and sign off.
Pack and Ship.
- Combustion chambers matched to the bore. Deshroud valve area.
Shape and polish. Call for pricing!
- Measure and record one combustion chamber volume $18
- Or balance all four volumes plus/minus 0.4cc $60
- Balance plus/minus 0.15cc $80
- Measure and match volumes with valves installed after seat cut $300
- Custom combustion chamber modifications such as high swirl
chambers, lower combustion chambers, stop chambers. Call for pricing!
- Modify Combustion chamber "Quench Area" to direct and shape
the explosion of combustion. $30/Cyl
- Polish Cam bearing Surface(s) $20
-
Blueprint Cam(s) $40/cam
- Lash Cam(s) $250
- Custom fit cam caps to head and camshafts WPC treatment Read More...
- Polish camshaft journals $40/cam
- Align bore cam journals and caps $40/cam
-
Machine oil groves in camshaft journals $40/cam
-
Machine oil retention grove in cam cap $35/cam
- Polish one set (16) cam cap dowel pins and dowel receiving bore.
Remove oxidation, rust and corrosion for proper fit, prevents
seizing and improperly located caps. $50
Valve Guides
- Valve guide replacement includes removal of valve guide, bore
prep. Hone guide to fit valve stems. $75 labor
Valve Springs
-
Blueprint Springs $60
- If utilizing heavy valve springs, hi rpm, fast cam ramp, we suggest
WPC treatment to cam caps and/or oil channel
modification. Call for pricing! Read more...
Honda/Acura Custom cylinder heads can be supplied outright. Contact us for availability and details. Stage V,VI and VII custom modifications available for COMPETITION USE ONLY!!!
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Honda/Acura - Head Refresh Procedure
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Honda/Acura - Stage I
Honda/Acura - Stage II - 
Honda/Acura - Stage III - 
Honda/Acura - Stage IV - 
