CAMSHAFT PROFILES FROM FLAT TAPPET TO SOLID ROLLER CAMSHAFT:
PICTURED ABOVE ARE "3" CAMSHAFT OF SIMILAR LIFTS BUT WITH VASTLY DIFFERENT POTENTIAL. I HOPE I CAN SHED LIGHT TO WHAT IS THE BEST APPLICATION FOR YOUR RACECAR/TRUCK OR WHATEVER MIGHT FLOAT YOUR BOAT AS FAR AS RACING.... BECAUSE THIS IS OUR PRIMARY ADDICTION> SPEED !
HYDRAULIC FLAT TAPPET DESIGN:
THE CAMSHAFT ON THE RIGHT OF THE PICTURE IS THE FLAT TAPPET TYPE THAT COMES WITH A HYDRAULIC OR SOLID TYPE LIFTER.
THE HYDRAULIC TYPE IS WHAT MOST ENGINES COMES WITH. THE VALVE LASH IS SET AT "0" OR NO LASH AND THE LIFTER TAKES UP THE SLACK THAT NORMALLY WOULD HAVE A PRE-SET GAP FROM THE FACTORY.
THE ADVANTAGE OF THIS TYPE CAM IS THE QUIETNESS OF ITS DESIGN. IT IS BASICALLY ZERO MAINTAINANCE, IS RELIABLE FOR MANY YEARS OF AN ENGINES LIFE. NO VALVE ADJUSTMENTS ARE PERFORMED DURING MAINTAINANCE SCHEDULES LIKE TUNE UPS OR OIL CHANGES.
THE VALVETRAIN FOR HYDRAULIC CAMS USUALLY COMES WITH A NON-ADJUSTABLE ROCKER ARMS OR VALVE COMPONENTS THAT DO NOT NEED SHIMS TO OPERATE PROPERLY. ALL CLEARANCES ARE HYDRAULICALLY CONTROLLED
AND RESULTS IN MANY YEARS OF TROUBLE FREE & QUIET OPERATON.
HOWEVER ALL THIS TROUBLE FREE DESIGN COMES WITH A SEVERE LIMITATION IN PERFORMANCE....MAINLY IN THE HIGH RPM DEPARTMENT!
THE DOWNFALL STARTS WITH THE LIFTERS INABILITY TO CONTROL "LIFTER PUMP UP" @ HIGHER ENGINE SPEEDS.
THIS DESIGN WILL BE UNABLE TO CONTROL THE VALVE AND VALVETRAIN AT EXTENDED SPEEDS AND THE RESULT WILL BE LIFTER TO PUSHROD AND ROCKER ARM SEPARATION WHERE THIS INDIVIDUAL OR ALL CANNOT FOLLOW THE PROFILE OF THE CAM LOBES FROM THE OPENING RAMPS AND THE CLOSING SIDE OF THE LOBES WHERE IT WILL CLOSE RAPIDLY AND BOUNCING THE VALVE OFF THE SEATS...A LOSS OF RPM POTENTIAL, HORSEPOWER AND PROBABLE PISTON TO VALVE CONTACT OR ALL THREE COMBINED TOGETHER TO CREATE AN ENGINE DISASTER CULMINATING IN YOU SPENDING MONEY TO FIX YOUR RIDE.
THIS CAM IS BEST LEFT FOR STOCK OR MILD HIGH PERFORMANCE APPLICATIONS MAINLY FOR STREET OR LIMITED RACETRACK USE......
SOLID FLAT TAPPET DESIGN:
THIS IS THE HIGH PERFORMANCE VERSION OF THE HYDRAULIC CAMSHAFT. USUALLY INSTALLED IN CERTAIN LIMITED PRODUCTION HIGH PERFORMANCE ENGINES FROM THE FACTORY.
IT IS BY ALL MEANS SIMILAR TO LOOK AT AND THE MAJOR DIFFERENCE IS IN THE LIFTERS WHICH ARE NOW SOLID WITH NO SELF ADJUSTING OR SPRING & PLUNGER DESIGN TO KEEP THE LASH AT ZERO AND FOR QUIET OF OPERATION.
SOLID CAMS ARE NOISY BY NATURE DUE TO THE VALVE LASH SETTING THAT IS PART AND PARCEL OF THIS TYPE OF CAMS. THIS LASH SETTING OR ROCKER ARM GAP WILL MAKE A CLICKING OR TICKING SOUND THAT MAY BE ANNOYING TO SOME BUT A DELIGHT TO THE HIGH PERFORMANCE ENTHUSIAST.
THIS SOUND BECOMES LESS AS THE RPMS GETS TO THE HIGHER RANGES AND THE ABSENCE OF A HYDRAULIC PLUNGER @ THE LIFTERS WILL ENABLE THIS TO GET HIGHER RPMs UNHEARD OF IN A HYDRAULIC CAM PROFILE.
WHEN SWITCHING FROM A HIGH PERFORMANCE HYDRAULIC TO A SOLID CAM, THE ENGINE GAINED A LOT MORE RPM AND HORSEPOWER OVER THE PREVIOUS HYDRAULIC DESIGN. ON TRACK PERFORMANCE WAS MORE IMPRESSIVE!
HOWEVER, THERE WAS THE CONSTANT ADJUSTMENT THAT HAD TO BE PERFORMED BEFORE A WEEKEND OF RACING.
ONE THING I LEARNED IS LOOSE OR MISADJUSTED LASH HAS A WAY OF BEATING UP THE VALVES IF LEFT UNCHECKED AND CAN ALSO DAMAGE THE TIP OF THE VALVE STEM!
USING CHEAP ROLLER ROCKER ARMS THAT KEEPS LOOSING ADJUSTMENTS AND COUPLED WITH INFERIOR PUSHRODS AND YOU HAD A HELL OF A TIME KEEPING EVERYTHING IN ORDER....
SWITCHING TO A MORE EXPENSIVE CRANE ROLLER ROCKER ARMS & PUSHRODS MADE A BIG DIFFERENCE IN VALVETRAIN PERFORMANCE & MAINTAINANCE!
BUT THIS ALSO READJUSTED MY WALLET ACCORDINGLY....THIS IS MY FIRST LESSON IN MOVING UP A NOTCH FROM A STREET SET-UP TO A SERIOUS STEP ABOVE.
THIS CAMSHAFT & VALVETRAIN COST MORE MONEY AND THE EXCHANGE IS A FASTER RACE CAR.....
( at this point in time i was experimenting with a new oil called "synthetic blend"
my first impression was that there was a lot less valve lash that is out of adjustment and the engine exhibited less wear and tear on bearings & the cylinder bore! )
ROLLER CAM:
NOW WE ARE GETTING TO THE SERIOUS AS A HEART ATTACK CAM AND RELATED VALVE COMPONENTS!
THERE ARE NO SHORT CUTS HERE AND IF BUDGET IS A CONSIDERATION THEN I ADVISE YOU STAY WITH A SOLID FLAT TAPPET TO SAVE YOU HEADACHES AND SERIOUS ENGINE FAILURE IF DONE INCOMPETENTLY!
IF YOU LOOK AT THE PICTURE ABOVE, THIS IS THE CAM ON THE LEFT SIDE.
COMPARE THIS TO THE SOLID/HYDRAULIC LOBE PROFILE ON THE RIGHT SIDE OF THE PICTURE AND YOU SEE THE RAPID ALMOST DRASTIC LIFT RAMP OF THE CAM LOBES. A FLAT TAPPET CANNOT FOLLOW THIS PROFILE AND WOULD BE INSTANTLY VAPORIZED TO GROUNDED METAL IF ATTEMPTED.....
TO MAKE THIS POSSIBLE A SOLID ROLLER CAM PROFILE USES A ROLLER TAPPET, SAME CONSTRUCTION AS A SOLID FLAT TAPPET EXCEPT A "WHEEL" IS UTILIZED TO ENABLE THE LIFTER TO FOLLOW THE RAPID RISE IN THE VALVE LIFTER RAMP!
ROLLER CAM PROFILES ARE DESIGNED FOR THE SERIOUS COMPETITION ENGINES. THEY REQUIRE HIGH COMPRESSION RATIOS TO COMPENSATE FOR THE LOSS OF DYNAMIC COMPRESSION PRESSURES. ( the actual compression the engine sees after the intake valve closes. usually significantly lower than the mechanical compression ratio!)
TURBO / SUPERCHARGE ENGINES WILL BENEFIT AS WELL DUE TO THE FASTER/RAPID VALVE OPENING EVENTS PERMITTING MORE COMPLETE CYLINDER FILLING FOR A GIVEN CRANK ANGLE. A MORE BROADER VALVE LIFT CURVE COMPARED TO A STANDARD CAMSHAFT ACROSS THE VALVE OPENING AND CLOSING EVENT OR CYCLE.
THE RAPID RISE IN THE LIFT OF THE VALVE REQUIRE A STIFFER VALVE SPRING TO KEEP THE LIFTER IN CONSTANT CONTACT WITH THE LOBE RAMP PROFILE!
ANOTHER AREA OF CONCERN IS THE ROCKER ARM AND PUSHROD DESIGN.
BOTH MUST BE EXTREMELY WELL BUILT TO RESIST FLEXING AND OR BENDING AFFECTING THE ACTUAL VALVE TIMING OR EVENTS. ANY VALVETRAIN RELATED FAILURE HERE WILL HAVE DISASTROUS CONSEQUENCE.....
THIS CAMSHAFT HAS THE ABILITY TO RUN AT VERY HIGH ENGINE SPEEDS AND CORRECTLY ENGINEERED PARTS ARE A MUST TO PREVENT ROLLER LIFTER,PUSHRODS AND ROCKER ARM SEPARATING ITSELF FROM THE LOBE PROFILE AND LOOSING ALL OR PART OF THIS CONTROL.
ROCKER ARM "GEOMETRY" MUST!!! BE CORRECT!
IF YOU DO NOT KNOW HOW TO DO THIS, GET OR PAY SOMEONE WHO DOES BECAUSE IF IT IS WRONG YOU WILL KNOW ABOUT IT QUICKLY.....
VALVE SPRING OPEN PRESSURES APPROACHING 950+ LBS AND CLOSE PRESSURES OF 350+ LBS WILL WIPE OUT A STANDARD PLAIN CAM BEARING......SO A ROLLER BEARINGS ARE USED AFTER BORING OUT THE CAM TUNNEL TO RETROFIT THIS BIGGER ROLLER UNITS. AT A MINIMUM I USE "COATED" CAM BEARINGS AND KEEP A CAREFUL WATCH FOR WEAR CAUSING A LOSS OF OIL PRESSURES.
ALWAYS USE A BRONZE OR STEEL GEAR TO DRIVE YOUR DISTRIBUTOR/OIL PUMP. THE STANDARD DRIVE GEARS WILL GET EATEN UP BY A ROLLER CAM DUE TO THEIR BILLET STEEL CONSTRUCTION. A STEEL THRUST PLATE ARE ALSO MANDATORY FOR THE SAME REASONS.
HYDRAULIC ROLLER CAM:
THIS IS THE CAMSHAFT IN THE MIDDLE OF THIS TRIO OF CAMSHAFTS ABOVE.
LIKE MOST ADVANCEMENTS IN AUTOMOTIVE TECHNOLOGY HAVING BEEN PROVEN AT THE RACETRACKS FIRST AND EVENTUALLY ENDING UP ON THE AUTOMOTIVE SHOWROOMS.
LIKE THE MICRO WAVE OVEN, TV REMOTE CONTROL, SOLID STATE REPLACING VACUUM TUBES IN OUR TV & STEREOS, THIS TECHNOLOGY WAS DERIVED FROM NASA's APOLLO PROGRAM CULMINATING ON MANS LANDING ON THE MOON!
AND ALSO THE ABSENCE OF ZIPPERS & BUTTONS REPLACED BY VELCRO IS PART OF THIS TECHNOLOGY! LOL
HYDRAULIC ROLLER CAMS IS ALSO IN THIS CATEGORY WHEN DETROIT REALIZED THE BENEFITS OF RACING ROLLER CAMS ABILITY TO FILL THE CYLINDERS EARLIER IN THE OPENING INTAKE & EXHAUST VALVE CYCLES BOOSTING POWER AND TORQUE ACROSS THE RPM SPECTRUM.
TAKING THE ROLLER CAM PROFILE AND ADAPTING A STANDARD HYDRAULIC LIFTER AND ATTACHING A WHEEL ALA SOLID ROLLER TYPE HAS BEEN THE RAGE IN CAM PROFILES FOR THE STREET AND ALSO TO CERTAIN DEGREE AT THE RACETRACKS!
(note the ramp lobe profile compared to the solid roller on its left....it is close but is not as severe an opening ramp and it is a lot more broader and quicker opening than the cam lobe on its right side> the flat tappet profile which it has replaced in a lot of applications.)
WHEN THE FIRST 5.0 MUSTANGS FIRST SHOWED UP IN 1985 COMPLETE WITH TUBULAR HEDDERS AND A 4 BARREL HOLLEY CARBURETOR. A NEW MODERN MUSCLECAR WAS BORN AND ONE OF THE COMPONENTS THAT MADE THIS A HIT WAS THE HYDRAULIC ROLLER CAM!
I WAS ONE OF THE FIRST TO TRACK TEST THIS CARS WHEN I WAS DOING R&D FOR KAUFMANN PRODUCTS OF DOWNEY CA.
WHEN I PROFILED THE STOCK 5.0 CAMSHAFT, I WAS IMPRESSED BY THE SHORT DURATION AND LIFT NUMBERS THAT WAS IN IT FROM OUR CAM DOCTOR'S COMPUTER READOUT.
( a friend of mine Oz Anderson invented this computer program that profiles cam duration,lift & lobe centers. all info. as ramp acceleration and deceleration rates are broken down in crank/cam degrees exposing the secrets of any camshaft to any racing engine builder looking at any advantage or clue from "captured" or "stolen" camshaft from the competition....hehe. )
THIS CAM HAD A LOT MORE "LIFT UNDER THE CURVE" COMPARED TO THE AVERAGE SOLID FLAT TAPPET CURRENTLY USED AT THIS POINT ON MANY STREET CARS. THIS MADE IT POSSIBLE TO PRODUCE MORE TORQUE AND HORSEPOWER ON A BROADER RPM RANGE.
SO TO PROVE ITS METTLE WE HEAD OUT TO THE RACE TRACK WITH MY FRIEND GENE ABAD WITH JUST A ROLLER ROCKER RATIO CHANGE THAT MADE IT FROM 1.6 TO A NEW 1.7 RATIO. THIS EFFECTIVELY RAISES OUR LIFT FROM .444 @ THE VALVE TO .472! A NET INCREASE OF .028 AT THE VALVE. THERE IS ALSO A NET GAIN IN DURATION OF PROBABLY 2-3 DEGREES @ .050 AND THIS SHOULD MAKE A DIFFERENCE WE CAN FEEL AT THE TRACK.....SO OFF WE WENT TO FREMONT DRAGWAY IN THE BAY AREA AND SEE WHAT THIS CAN DO WITH A 150 SHOT OF NITROUS IN IT!
(the .028 net gain to some may be "insignificant" because it is gain at maximum lift...however the uninformed or clueless types fail to understand this .028 is "across" the full lift event giving a bigger valve open window.)
FIRST PASS WITH A BRAND NEW CAR WITH SLICKS AND A 150 SHOT OF NITROUS NETTED AN 11.70 PASS WITH EVERYTHING ALL STOCK EVEN THE MUFFLERS !
THIS ENGINE IS NO DIFFERENT THAN WHAT EVERYONE WAS RUNNING THEN ONLY THE FUEL INJECTION AND THIS MYSTERIOUS HYDRAULIC ROLLER.......
FAST FORWARD TO ANOTHER STREET CAR AND NOW MY COUSIN'S SNYDER ROTOLS PRISTINE 5.0 MUSTANG WITH A NOW EXPERIMENTAL HYDRAULIC ROLLER THAT I HAD "CUSTOM MADE"> DISPLACING 224 DURATION @ .050 AND A LIFT OF 540 @ THE VALVE. THIS NUMBERS AT THE CAM ARE VERY SIMILAR TO THE CAMSHAFT I RAN THAT WON THE MUSCLECAR NATIONALS CHAMPIONSHIPS IN BAKERSFIELD IN 1989
AND TO MAKE THE COMPARISON EVEN BETTER SNYDER IS USING THE HEADS I RAN ON THIS WINNING RACE CAR! THE ONLY DIFFERENCE IS THE ENGINE IN SNYDER'S MUSTANG IS A ABOUT 50 INCHES OR 1 LITER SMALLER.
I CAN STILL MAKE A COMPARISON SUBTRACTING THE DIFFERENCE IN DISPLACEMENT AND I SHOULD HAVE A GOOD FEEDBACK WITH THIS NEW CAMSHAFT......i was already curious of this new cam type because the lobes are almost like a full racing roller cam profile!
10.80's @ 118 MPH IN THE 1/4 MILE AND THIS AT A HIGH ALTITUDE RACETRACK IN PALMDALE! ON A STREET CAR HE DRIVES ON THE STREETS OF VAN NUYS......wow!
at this juncture he was one of if not my fastest street car all factory interior,stereo,a/c and yes power steering! this on a sea level racetrack will run 10.30-1040.
THIS HYDRAULIC ROLLER I REALIZED IS THE STUFF FOR "KILLER STREET" ENGINES.
SNYDERS CAR BASICALLY EQUALED MY OLD ENGINE DISPLACING 1 LITER/50 CUBIC INCHES LESS AND THE ONLY DIFFERENCE IS THE CAMSHAFT AND A LOT LESS ENGINE SIZE. THIS COMPARISON WAS DONE WITH MY OLD RACECARS HEADS RUNNING IN HIS CAR.
FROM THAT POINT ON "ALL" SERIOUS STREET ENGINES I BUILD RUNS A HYDRAULIC ROLLER WITH MORE ADVANCE LOBE, DURATION AND LIFT FIGURES.
THERE ARE NO SUBSTITUTES SHORT OF A FULL SOLID ROLLER CAM AND I CAN HARDLY CALL A SOLID ROLLER A STREETABLE CAMSHAFT!
TODAY.... HYDRAULIC ROLLER CAMS INABILITY TO RPM HIGH HAS BEEN FIGURED OUT BY MANY OUT THERE RUNNING THIS CAMS IN COMPETITION.
THEY ARE AS FOLLOWS:
-SETTING THE VALVE ADJUSTMENT USUALLY SET 1 TO 2 TURNS FROM ZERO LASH, BACKING THIS OFF TO A NEW SETTING OF 1/8 TO 1/16 FROM ZERO LASH! THIS PREVENTS HYDRAULIC LIFTER PUMPING UP AT HIGH RPMS. ALSO SOME WILL MODIFY THE "RETAINER RING" TO A MORE HEAVIER DUTY PIECE TO KEEP THE HYDRAULIC PLUNGER IN ITS PLACE.
(the wire retainer used here has a possibility of failing when you do this...)
-SHIMMING THE INSIDE OF THE HYDRAULIC LIFTER TO LIMIT THE COMPRESSED TRAVEL AND MAKES THE LIFTER ACT AS A SOLID ROLLER CAM/TAPPETS.
-USING NEW LIFTERS AND "BOTTOMING" OUT THE TRAVEL AND THIS COMPLETELY ELIMINATES THE HYDRAULIC SYSTEM AND ACTS LIKE A SOLID LIFTER WITHOUT VIOLATING RULES ON MODIFYING THE LIFTERS THAT IS DONE WITH THE 2 FORMER TIPS ABOVE.
*THIS HAS TO BE DONE "PRECISELY" AND WITH "CAREFUL ATTENTION" TO DETAILS........THE REWARDS ARE A LOT OF UNBELIVABLE RPMs THOUGHT OF AS NOT POSSIBLE WITH A HYDRAULIC CAMSHAFT !!!
TO WRAP THIS UP AND HELP IN YOUR DECISION IN CAM SELECTION THE POTENTIAL FOR POWER IS RANKED IN THIS MANNER....
#1 SOLID ROLLER CAM
#2 HYDRAULIC ROLLER CAM
#3 SOLID FLAT TAPPET
#4 HYDRAULIC FLAT TAPPET
BEN ALAMEDA @ PARA TECH, FB, BENALAMEDARACING.COM
(tech in memory of friend & mentor Chuck
PICTURED ABOVE ARE "3" CAMSHAFT OF SIMILAR LIFTS BUT WITH VASTLY DIFFERENT POTENTIAL. I HOPE I CAN SHED LIGHT TO WHAT IS THE BEST APPLICATION FOR YOUR RACECAR/TRUCK OR WHATEVER MIGHT FLOAT YOUR BOAT AS FAR AS RACING.... BECAUSE THIS IS OUR PRIMARY ADDICTION> SPEED !
HYDRAULIC FLAT TAPPET DESIGN:
THE CAMSHAFT ON THE RIGHT OF THE PICTURE IS THE FLAT TAPPET TYPE THAT COMES WITH A HYDRAULIC OR SOLID TYPE LIFTER.
THE HYDRAULIC TYPE IS WHAT MOST ENGINES COMES WITH. THE VALVE LASH IS SET AT "0" OR NO LASH AND THE LIFTER TAKES UP THE SLACK THAT NORMALLY WOULD HAVE A PRE-SET GAP FROM THE FACTORY.
THE ADVANTAGE OF THIS TYPE CAM IS THE QUIETNESS OF ITS DESIGN. IT IS BASICALLY ZERO MAINTAINANCE, IS RELIABLE FOR MANY YEARS OF AN ENGINES LIFE. NO VALVE ADJUSTMENTS ARE PERFORMED DURING MAINTAINANCE SCHEDULES LIKE TUNE UPS OR OIL CHANGES.
THE VALVETRAIN FOR HYDRAULIC CAMS USUALLY COMES WITH A NON-ADJUSTABLE ROCKER ARMS OR VALVE COMPONENTS THAT DO NOT NEED SHIMS TO OPERATE PROPERLY. ALL CLEARANCES ARE HYDRAULICALLY CONTROLLED
AND RESULTS IN MANY YEARS OF TROUBLE FREE & QUIET OPERATON.
HOWEVER ALL THIS TROUBLE FREE DESIGN COMES WITH A SEVERE LIMITATION IN PERFORMANCE....MAINLY IN THE HIGH RPM DEPARTMENT!
THE DOWNFALL STARTS WITH THE LIFTERS INABILITY TO CONTROL "LIFTER PUMP UP" @ HIGHER ENGINE SPEEDS.
THIS DESIGN WILL BE UNABLE TO CONTROL THE VALVE AND VALVETRAIN AT EXTENDED SPEEDS AND THE RESULT WILL BE LIFTER TO PUSHROD AND ROCKER ARM SEPARATION WHERE THIS INDIVIDUAL OR ALL CANNOT FOLLOW THE PROFILE OF THE CAM LOBES FROM THE OPENING RAMPS AND THE CLOSING SIDE OF THE LOBES WHERE IT WILL CLOSE RAPIDLY AND BOUNCING THE VALVE OFF THE SEATS...A LOSS OF RPM POTENTIAL, HORSEPOWER AND PROBABLE PISTON TO VALVE CONTACT OR ALL THREE COMBINED TOGETHER TO CREATE AN ENGINE DISASTER CULMINATING IN YOU SPENDING MONEY TO FIX YOUR RIDE.
THIS CAM IS BEST LEFT FOR STOCK OR MILD HIGH PERFORMANCE APPLICATIONS MAINLY FOR STREET OR LIMITED RACETRACK USE......
SOLID FLAT TAPPET DESIGN:
THIS IS THE HIGH PERFORMANCE VERSION OF THE HYDRAULIC CAMSHAFT. USUALLY INSTALLED IN CERTAIN LIMITED PRODUCTION HIGH PERFORMANCE ENGINES FROM THE FACTORY.
IT IS BY ALL MEANS SIMILAR TO LOOK AT AND THE MAJOR DIFFERENCE IS IN THE LIFTERS WHICH ARE NOW SOLID WITH NO SELF ADJUSTING OR SPRING & PLUNGER DESIGN TO KEEP THE LASH AT ZERO AND FOR QUIET OF OPERATION.
SOLID CAMS ARE NOISY BY NATURE DUE TO THE VALVE LASH SETTING THAT IS PART AND PARCEL OF THIS TYPE OF CAMS. THIS LASH SETTING OR ROCKER ARM GAP WILL MAKE A CLICKING OR TICKING SOUND THAT MAY BE ANNOYING TO SOME BUT A DELIGHT TO THE HIGH PERFORMANCE ENTHUSIAST.
THIS SOUND BECOMES LESS AS THE RPMS GETS TO THE HIGHER RANGES AND THE ABSENCE OF A HYDRAULIC PLUNGER @ THE LIFTERS WILL ENABLE THIS TO GET HIGHER RPMs UNHEARD OF IN A HYDRAULIC CAM PROFILE.
WHEN SWITCHING FROM A HIGH PERFORMANCE HYDRAULIC TO A SOLID CAM, THE ENGINE GAINED A LOT MORE RPM AND HORSEPOWER OVER THE PREVIOUS HYDRAULIC DESIGN. ON TRACK PERFORMANCE WAS MORE IMPRESSIVE!
HOWEVER, THERE WAS THE CONSTANT ADJUSTMENT THAT HAD TO BE PERFORMED BEFORE A WEEKEND OF RACING.
ONE THING I LEARNED IS LOOSE OR MISADJUSTED LASH HAS A WAY OF BEATING UP THE VALVES IF LEFT UNCHECKED AND CAN ALSO DAMAGE THE TIP OF THE VALVE STEM!
USING CHEAP ROLLER ROCKER ARMS THAT KEEPS LOOSING ADJUSTMENTS AND COUPLED WITH INFERIOR PUSHRODS AND YOU HAD A HELL OF A TIME KEEPING EVERYTHING IN ORDER....
SWITCHING TO A MORE EXPENSIVE CRANE ROLLER ROCKER ARMS & PUSHRODS MADE A BIG DIFFERENCE IN VALVETRAIN PERFORMANCE & MAINTAINANCE!
BUT THIS ALSO READJUSTED MY WALLET ACCORDINGLY....THIS IS MY FIRST LESSON IN MOVING UP A NOTCH FROM A STREET SET-UP TO A SERIOUS STEP ABOVE.
THIS CAMSHAFT & VALVETRAIN COST MORE MONEY AND THE EXCHANGE IS A FASTER RACE CAR.....
( at this point in time i was experimenting with a new oil called "synthetic blend"
my first impression was that there was a lot less valve lash that is out of adjustment and the engine exhibited less wear and tear on bearings & the cylinder bore! )
ROLLER CAM:
NOW WE ARE GETTING TO THE SERIOUS AS A HEART ATTACK CAM AND RELATED VALVE COMPONENTS!
THERE ARE NO SHORT CUTS HERE AND IF BUDGET IS A CONSIDERATION THEN I ADVISE YOU STAY WITH A SOLID FLAT TAPPET TO SAVE YOU HEADACHES AND SERIOUS ENGINE FAILURE IF DONE INCOMPETENTLY!
IF YOU LOOK AT THE PICTURE ABOVE, THIS IS THE CAM ON THE LEFT SIDE.
COMPARE THIS TO THE SOLID/HYDRAULIC LOBE PROFILE ON THE RIGHT SIDE OF THE PICTURE AND YOU SEE THE RAPID ALMOST DRASTIC LIFT RAMP OF THE CAM LOBES. A FLAT TAPPET CANNOT FOLLOW THIS PROFILE AND WOULD BE INSTANTLY VAPORIZED TO GROUNDED METAL IF ATTEMPTED.....
TO MAKE THIS POSSIBLE A SOLID ROLLER CAM PROFILE USES A ROLLER TAPPET, SAME CONSTRUCTION AS A SOLID FLAT TAPPET EXCEPT A "WHEEL" IS UTILIZED TO ENABLE THE LIFTER TO FOLLOW THE RAPID RISE IN THE VALVE LIFTER RAMP!
ROLLER CAM PROFILES ARE DESIGNED FOR THE SERIOUS COMPETITION ENGINES. THEY REQUIRE HIGH COMPRESSION RATIOS TO COMPENSATE FOR THE LOSS OF DYNAMIC COMPRESSION PRESSURES. ( the actual compression the engine sees after the intake valve closes. usually significantly lower than the mechanical compression ratio!)
TURBO / SUPERCHARGE ENGINES WILL BENEFIT AS WELL DUE TO THE FASTER/RAPID VALVE OPENING EVENTS PERMITTING MORE COMPLETE CYLINDER FILLING FOR A GIVEN CRANK ANGLE. A MORE BROADER VALVE LIFT CURVE COMPARED TO A STANDARD CAMSHAFT ACROSS THE VALVE OPENING AND CLOSING EVENT OR CYCLE.
THE RAPID RISE IN THE LIFT OF THE VALVE REQUIRE A STIFFER VALVE SPRING TO KEEP THE LIFTER IN CONSTANT CONTACT WITH THE LOBE RAMP PROFILE!
ANOTHER AREA OF CONCERN IS THE ROCKER ARM AND PUSHROD DESIGN.
BOTH MUST BE EXTREMELY WELL BUILT TO RESIST FLEXING AND OR BENDING AFFECTING THE ACTUAL VALVE TIMING OR EVENTS. ANY VALVETRAIN RELATED FAILURE HERE WILL HAVE DISASTROUS CONSEQUENCE.....
THIS CAMSHAFT HAS THE ABILITY TO RUN AT VERY HIGH ENGINE SPEEDS AND CORRECTLY ENGINEERED PARTS ARE A MUST TO PREVENT ROLLER LIFTER,PUSHRODS AND ROCKER ARM SEPARATING ITSELF FROM THE LOBE PROFILE AND LOOSING ALL OR PART OF THIS CONTROL.
ROCKER ARM "GEOMETRY" MUST!!! BE CORRECT!
IF YOU DO NOT KNOW HOW TO DO THIS, GET OR PAY SOMEONE WHO DOES BECAUSE IF IT IS WRONG YOU WILL KNOW ABOUT IT QUICKLY.....
VALVE SPRING OPEN PRESSURES APPROACHING 950+ LBS AND CLOSE PRESSURES OF 350+ LBS WILL WIPE OUT A STANDARD PLAIN CAM BEARING......SO A ROLLER BEARINGS ARE USED AFTER BORING OUT THE CAM TUNNEL TO RETROFIT THIS BIGGER ROLLER UNITS. AT A MINIMUM I USE "COATED" CAM BEARINGS AND KEEP A CAREFUL WATCH FOR WEAR CAUSING A LOSS OF OIL PRESSURES.
ALWAYS USE A BRONZE OR STEEL GEAR TO DRIVE YOUR DISTRIBUTOR/OIL PUMP. THE STANDARD DRIVE GEARS WILL GET EATEN UP BY A ROLLER CAM DUE TO THEIR BILLET STEEL CONSTRUCTION. A STEEL THRUST PLATE ARE ALSO MANDATORY FOR THE SAME REASONS.
HYDRAULIC ROLLER CAM:
THIS IS THE CAMSHAFT IN THE MIDDLE OF THIS TRIO OF CAMSHAFTS ABOVE.
LIKE MOST ADVANCEMENTS IN AUTOMOTIVE TECHNOLOGY HAVING BEEN PROVEN AT THE RACETRACKS FIRST AND EVENTUALLY ENDING UP ON THE AUTOMOTIVE SHOWROOMS.
LIKE THE MICRO WAVE OVEN, TV REMOTE CONTROL, SOLID STATE REPLACING VACUUM TUBES IN OUR TV & STEREOS, THIS TECHNOLOGY WAS DERIVED FROM NASA's APOLLO PROGRAM CULMINATING ON MANS LANDING ON THE MOON!
AND ALSO THE ABSENCE OF ZIPPERS & BUTTONS REPLACED BY VELCRO IS PART OF THIS TECHNOLOGY! LOL
HYDRAULIC ROLLER CAMS IS ALSO IN THIS CATEGORY WHEN DETROIT REALIZED THE BENEFITS OF RACING ROLLER CAMS ABILITY TO FILL THE CYLINDERS EARLIER IN THE OPENING INTAKE & EXHAUST VALVE CYCLES BOOSTING POWER AND TORQUE ACROSS THE RPM SPECTRUM.
TAKING THE ROLLER CAM PROFILE AND ADAPTING A STANDARD HYDRAULIC LIFTER AND ATTACHING A WHEEL ALA SOLID ROLLER TYPE HAS BEEN THE RAGE IN CAM PROFILES FOR THE STREET AND ALSO TO CERTAIN DEGREE AT THE RACETRACKS!
(note the ramp lobe profile compared to the solid roller on its left....it is close but is not as severe an opening ramp and it is a lot more broader and quicker opening than the cam lobe on its right side> the flat tappet profile which it has replaced in a lot of applications.)
WHEN THE FIRST 5.0 MUSTANGS FIRST SHOWED UP IN 1985 COMPLETE WITH TUBULAR HEDDERS AND A 4 BARREL HOLLEY CARBURETOR. A NEW MODERN MUSCLECAR WAS BORN AND ONE OF THE COMPONENTS THAT MADE THIS A HIT WAS THE HYDRAULIC ROLLER CAM!
I WAS ONE OF THE FIRST TO TRACK TEST THIS CARS WHEN I WAS DOING R&D FOR KAUFMANN PRODUCTS OF DOWNEY CA.
WHEN I PROFILED THE STOCK 5.0 CAMSHAFT, I WAS IMPRESSED BY THE SHORT DURATION AND LIFT NUMBERS THAT WAS IN IT FROM OUR CAM DOCTOR'S COMPUTER READOUT.
( a friend of mine Oz Anderson invented this computer program that profiles cam duration,lift & lobe centers. all info. as ramp acceleration and deceleration rates are broken down in crank/cam degrees exposing the secrets of any camshaft to any racing engine builder looking at any advantage or clue from "captured" or "stolen" camshaft from the competition....hehe. )
THIS CAM HAD A LOT MORE "LIFT UNDER THE CURVE" COMPARED TO THE AVERAGE SOLID FLAT TAPPET CURRENTLY USED AT THIS POINT ON MANY STREET CARS. THIS MADE IT POSSIBLE TO PRODUCE MORE TORQUE AND HORSEPOWER ON A BROADER RPM RANGE.
SO TO PROVE ITS METTLE WE HEAD OUT TO THE RACE TRACK WITH MY FRIEND GENE ABAD WITH JUST A ROLLER ROCKER RATIO CHANGE THAT MADE IT FROM 1.6 TO A NEW 1.7 RATIO. THIS EFFECTIVELY RAISES OUR LIFT FROM .444 @ THE VALVE TO .472! A NET INCREASE OF .028 AT THE VALVE. THERE IS ALSO A NET GAIN IN DURATION OF PROBABLY 2-3 DEGREES @ .050 AND THIS SHOULD MAKE A DIFFERENCE WE CAN FEEL AT THE TRACK.....SO OFF WE WENT TO FREMONT DRAGWAY IN THE BAY AREA AND SEE WHAT THIS CAN DO WITH A 150 SHOT OF NITROUS IN IT!
(the .028 net gain to some may be "insignificant" because it is gain at maximum lift...however the uninformed or clueless types fail to understand this .028 is "across" the full lift event giving a bigger valve open window.)
FIRST PASS WITH A BRAND NEW CAR WITH SLICKS AND A 150 SHOT OF NITROUS NETTED AN 11.70 PASS WITH EVERYTHING ALL STOCK EVEN THE MUFFLERS !
THIS ENGINE IS NO DIFFERENT THAN WHAT EVERYONE WAS RUNNING THEN ONLY THE FUEL INJECTION AND THIS MYSTERIOUS HYDRAULIC ROLLER.......
FAST FORWARD TO ANOTHER STREET CAR AND NOW MY COUSIN'S SNYDER ROTOLS PRISTINE 5.0 MUSTANG WITH A NOW EXPERIMENTAL HYDRAULIC ROLLER THAT I HAD "CUSTOM MADE"> DISPLACING 224 DURATION @ .050 AND A LIFT OF 540 @ THE VALVE. THIS NUMBERS AT THE CAM ARE VERY SIMILAR TO THE CAMSHAFT I RAN THAT WON THE MUSCLECAR NATIONALS CHAMPIONSHIPS IN BAKERSFIELD IN 1989
AND TO MAKE THE COMPARISON EVEN BETTER SNYDER IS USING THE HEADS I RAN ON THIS WINNING RACE CAR! THE ONLY DIFFERENCE IS THE ENGINE IN SNYDER'S MUSTANG IS A ABOUT 50 INCHES OR 1 LITER SMALLER.
I CAN STILL MAKE A COMPARISON SUBTRACTING THE DIFFERENCE IN DISPLACEMENT AND I SHOULD HAVE A GOOD FEEDBACK WITH THIS NEW CAMSHAFT......i was already curious of this new cam type because the lobes are almost like a full racing roller cam profile!
10.80's @ 118 MPH IN THE 1/4 MILE AND THIS AT A HIGH ALTITUDE RACETRACK IN PALMDALE! ON A STREET CAR HE DRIVES ON THE STREETS OF VAN NUYS......wow!
at this juncture he was one of if not my fastest street car all factory interior,stereo,a/c and yes power steering! this on a sea level racetrack will run 10.30-1040.
THIS HYDRAULIC ROLLER I REALIZED IS THE STUFF FOR "KILLER STREET" ENGINES.
SNYDERS CAR BASICALLY EQUALED MY OLD ENGINE DISPLACING 1 LITER/50 CUBIC INCHES LESS AND THE ONLY DIFFERENCE IS THE CAMSHAFT AND A LOT LESS ENGINE SIZE. THIS COMPARISON WAS DONE WITH MY OLD RACECARS HEADS RUNNING IN HIS CAR.
FROM THAT POINT ON "ALL" SERIOUS STREET ENGINES I BUILD RUNS A HYDRAULIC ROLLER WITH MORE ADVANCE LOBE, DURATION AND LIFT FIGURES.
THERE ARE NO SUBSTITUTES SHORT OF A FULL SOLID ROLLER CAM AND I CAN HARDLY CALL A SOLID ROLLER A STREETABLE CAMSHAFT!
TODAY.... HYDRAULIC ROLLER CAMS INABILITY TO RPM HIGH HAS BEEN FIGURED OUT BY MANY OUT THERE RUNNING THIS CAMS IN COMPETITION.
THEY ARE AS FOLLOWS:
-SETTING THE VALVE ADJUSTMENT USUALLY SET 1 TO 2 TURNS FROM ZERO LASH, BACKING THIS OFF TO A NEW SETTING OF 1/8 TO 1/16 FROM ZERO LASH! THIS PREVENTS HYDRAULIC LIFTER PUMPING UP AT HIGH RPMS. ALSO SOME WILL MODIFY THE "RETAINER RING" TO A MORE HEAVIER DUTY PIECE TO KEEP THE HYDRAULIC PLUNGER IN ITS PLACE.
(the wire retainer used here has a possibility of failing when you do this...)
-SHIMMING THE INSIDE OF THE HYDRAULIC LIFTER TO LIMIT THE COMPRESSED TRAVEL AND MAKES THE LIFTER ACT AS A SOLID ROLLER CAM/TAPPETS.
-USING NEW LIFTERS AND "BOTTOMING" OUT THE TRAVEL AND THIS COMPLETELY ELIMINATES THE HYDRAULIC SYSTEM AND ACTS LIKE A SOLID LIFTER WITHOUT VIOLATING RULES ON MODIFYING THE LIFTERS THAT IS DONE WITH THE 2 FORMER TIPS ABOVE.
*THIS HAS TO BE DONE "PRECISELY" AND WITH "CAREFUL ATTENTION" TO DETAILS........THE REWARDS ARE A LOT OF UNBELIVABLE RPMs THOUGHT OF AS NOT POSSIBLE WITH A HYDRAULIC CAMSHAFT !!!
TO WRAP THIS UP AND HELP IN YOUR DECISION IN CAM SELECTION THE POTENTIAL FOR POWER IS RANKED IN THIS MANNER....
#1 SOLID ROLLER CAM
#2 HYDRAULIC ROLLER CAM
#3 SOLID FLAT TAPPET
#4 HYDRAULIC FLAT TAPPET
BEN ALAMEDA @ PARA TECH, FB, BENALAMEDARACING.COM
(tech in memory of friend & mentor Chuck
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