HIGH TECH ELECTRONIC FUEL INJECTION VS. LOW TECH CARBURATOR:
THERE ARE A LOT OF DISCUSSIONS ON WHICH IS BETTER AND I AM SURE I WILL ADD FUEL TO THE FIRE!
OPINIONS WITHSTANDING, I WILL BASE IT ON WHAT I SEE AT THE RACETRACKS AND NOT WHAT OTHERS TELL ME OR WHAT I HAVE HEARD.......
EXPERIENCE BUILDING BOTH GIVES ME AN INVALUABLE DATA THAT I CAN PUT TOGETHER GIVING AN HONEST OPINION ON THE ADVANTAGES AND DISADVANTAGES OF EITHER ONE.
ELECTRONIC FUEL INJECTION TODAY ARE HIGH TECHNOLOGY PROVIDING CONSISTENT AIR/FUEL RATIO ACROSS THE RPM RANGE.
"ACURACY IN AIR/FUEL RATIOS" GIVES IT AN EDGE IN THE TUNING WINDOW UNATTAINED BEFORE WITH MECHANICAL FUEL INJECTION OR A CARBURETOR.
CARBURETORS MEANWHILE ARE LOW TECH AND DUMB!
CRUDE AND ANCIENT COMPAIRED TO
COMPUTER CONTROLLED E.F.I.
MEANWHILE SOME RACING CARBS TODAY COME WITH NEW "HIGH TECH VENTURIS" AND METERING BLOCKS.
HOWEVER IT NEEDS A COMPETENT TUNER TO GET MOST OUT OF THIS COMBINATION.
ADJUSTMENTS HAS TO BE INTERPRETED BY THE TUNER WHEREAS COMPUTERIZE F.I. GIVES FEEDBACK FROM SENSORS AND THE DISPLAY SCREEN.
HOWEVER, THE E.F.I. TUNER HAS TO BE ON TOP OF HIS GAME AND MAKE THE PROPER ADJUSTMENTS.
IF HE IS INCOMPETENT IN HIS CRAFT?
THEN HIGH TECH HAS NO ADVANTAGE WHATSOEVER!
EFI DELIVERS CONSISTENT AIR/FUEL MIXTURES "ALL" THE TIME AS PROGRAMMED.
CARBS CAN ALSO DELIVER A CONSISTENT AIR/FUEL BUT ONLY "MOST" OF THE TIME.
HOWEVER! RECENT HIGH TECH RACING CARBS CAN GIVE AN EFI A RUN FOR ITS MONEY....
SO WHERE IS THE DIFFERENCE?
IT IS IN THE "EMULSIFIED" AND "ATOMIZED" CONDITION OF THE AIR/FUEL MIXTURE INSIDE THE INTAKE PORTS!
A CONDITION PERMITING FASTER BUILD-UP OF THE RPM'S RESULTING IN +5-6% MORE HORSEPOWER OVER EFI. CONSIDERING ALL PERIMETERS ARE EQUAL.
JOULE-THOMSON EFFECT:
ANOTHER ADVANTAGE FEW PEOPLE KNOW IS THE "JOULE-THOMSON" EFFECT THAT DECREASES INLET TEMPERATURES OF THE AIR/FUEL MIXTURE BY AT LEAST 20* DEGREES!
THIS MEANS THAT COMPARING EFI VS. CARB CARB. ENGINES SEES FOR EXAMPLE> AN 80*F DEGREE INTAKE TEMPERATURE.....
MEANWHILE AN EFI WILL BE RUNNING AT APPROXIMATELY 100*F OR MORE!
AN ADVANTAGE THAT IS VERY HARD TO OVERCOME IN ANY COMPETITION ALBEIT A CLOSE ONE!
CARB. INTAKES PROVIDES DENSER, COOLER & "FUEL-MISTED" MIXTURE QUALITY.
ALLOWS MORE HORSEPOWER COMPARED TO A "DRY" & "HOT" EFI INTAKE MANIFOLD.
( This drop in inlet temp. is caused by the J-T effect when the fuel droplets are discharge below the venture. Causing an immediate "drop" in temperatures.
You can test this theory by running your air compressor till it is hot @ the tank & lines.
Using a nozzle while pressing the trigger,
note the temperature. of the exiting air past the nozzles...?
it will be much cooler than the air in the pressure line/tank!
This is the J-T effect!
Introducing a "small amount of water spray" also adds to the cooling much like fuel stream/small droplets being discharge directly at the bottom of a carb ).
THE EXPLANATION ABOVE HAS BEEN PROVEN SEVERAL TIMES WHEN I SWITCHED FROM EFI TO CARBS OR VICE VERSA.
THE IMMEDIATE COMMENT IS THE CARBS RPM RISE IS MUCH QUICKER ACROSS THE RPM RANGE AND THE RESPONSE IS MUCH BETTER!
E.F.I. ADVANTAGES:
CARB. ENGINES HAS LESS "TORQUE" DOWN LOW AND THIS IS WHERE EFI EXCELS
THE SUPERIORITY OF CONSISTENT DISTRIBUTION OF FUEL INSIDE THE INTAKE MANIFOLDS ON THE LOW-MID-HIGH RPM RANGES CANNOT BE DISMISSED.
E.F.I. INTAKE RUNNER LENGTH:
ANOTHER ASPECT IS THE LONG INTAKE MANIFOLD RUNNERS ON EFI COMPARED TO CARBS.
"RAM INDUCTION" OR RAM TUNING ON EFI MANIFOLDS INCREASES VOLUMETRIC EFFICIENCY OR WHAT IS CALLED CYLINDER FILLING BY A SIGNIFICANT MARGIN.
BOOSTING TORQUE UNHEARD OR UNSEEN IN CARB ENGINES.
SPECIALLY IF THE "LENGTH IS TUNED" TO A SPECIFIC RPM RANGE AND IT WILL OUTPULL JUST ABOUT ANY CARB ENGINE ANYWHERE!
EFI DISADVANTAGES:
THE DRAWBACK IS, LONG RUNNER LENGTHS CREATES "PUMPING LOSSES" THAT KILLS HORSEPOWER DUE ADDED INTAKE RESTRICTIONS ASSOCIATED WITH LONG PORTS.
MOST CARB MANIFOLDS ARE GENERALLY SHORTER IN LENGTH AND THEREFORE MORE HIGH RPM ORIENTED THAN THE TYPICAL EFI MANIFOLDS. HENCE THEY HAVE LESS PUMPING LOSS AT ELEVATED ENGINE SPEEDS.
MY EXPERIENCE AT DRAGSTRIPS WITH MOTORCYCLES OR CARS,
CARBS WINS HANDS DOWN....
FASTER ALL ELSE BEING EQUAL!
ON THE OFF-ROAD OR HILL CLIMB RACERS?
THE EFI WINS DECISIVELY!
(Sometimes exception are on high speed off-road courses )
EFI'S ARE NOT AFFECTED AS EASILY AS A CARB ENGINE AT DIFFICULT ANGLES >
CLIMBING OR DESCENDING.....
CARBS ALSO GETS AFFECTED AND LOOSES "FLOAT LEVEL CONTROL" WHEN OFF-ROAD TRUCKS GET "AIRBORNE" OR SPECIALLY ON THE WHOOPSIE DOOS.
( several big n small fast jumps one after the other )
IT FLOODS EVEN WHEN USING BOWL EXTENSIONS, BAFFLES, VENT TUBES AND OR "CATHEDRAL" TYPE FLOATS.
I GET COMPLAINTS FROM SEVERAL OF MY OFF-ROAD CUSTOMERS SWITCHING TO EFI FROM CARBS BECAUSE OF THIS DILEMMA.
LAST BUT NOT LEAST DUST AND DIRT HAVE A DISASTROUS EFFECT ON THE CARBS METERING ABILITIES WHEN AIR BLEEDS ARE BLOCKED BY DIRT PARTICLES.
THEREFORE SUPERIOR AIR FILTRATION IS A MUST HAVE.
EFI ONLY DRAWBACK HERE IS ITS NEED FOR A CLEAN FUEL FILTER AND A GOOD AIR CLEANER ASSEMBLY.
ON ROAD- RACE ENGINES, THE HIGHER "G" FORCES AT THE CORNERS? THE BETTER EFI'S ADVANTAGES.
AT THIS POINT THE CARBS HORSEPOWER ADVANTAGE IS LESSENED IF IT STUMBLES AND SURGES FROM A CORNER OR INTO A CORNER STARTING TO STALL....
HOWEVER ADVANCES IN VENTURI AND METERING BY SOME ALL OUT RACING CARB MANUFACTURERS MAKES THIS AN ALMOST NON- EXISTENT PROBLEM.
I ALSO WITHHOLD COMMENTS UNTIL I SEE AN F-1 OR INDY CAR RUN A CARBURETOR ON A VERY DEMANDING ROAD COURSE......
I KNOW ELEVATED "G"-FORCES ON CORNERS WILL KILL A CARBURETOR!
( As a side note... Aircraft like the German Lufwaffe Me-109 fighter came with Daimler-Benz (Mercedes Benz) fuel-injection on their engines. Contrary against Allied British Spitfire's "carbureted" fighter engines of WW-2 era.
The British planes will surge and stall out every time the Germans pull a negative "G" maneuver to get away from the British fighters and other prolonged or sustained maneuvers....Advantage F.I. ! LOL ).
EFI'S BIG ADVANTAGE IN MILEAGE & EMISSIONS:
SUPERIOR AND CONSISTENT FUEL MIXURE INSIDE THE INTAKE PORTS YIELDS BETTER MILEAGE AND EMISSION COMPLIANCE.
CARBURETORS CRUDE MIXING ABILITY TAKES A BACK SEAT TO EFI'S.
MODIFIED BOOSTER VENTURIS HOWEVER CAN ONLY DO SO MUCH.
BECAUSE, WHEN FUEL DISCHARGES BELOW THE VENTURIS/THROTTLE PLATES IN A MANIFOLD PLENUM?
PROPER FUEL- DISTRIBUTION IS AT THE "MERCY" OF THE MANIFOLD DESIGN!
IT HAS TO BE ABLE TO FLOW SIMILAR/EQUAL AMOUNTS OF FUEL MIX ON ALL THE PORTS WHILE KEEPING THE A/F MIXTURE IN SUSPENSION.
ANOTHER IMPORTANT FACTOR IS HEAT OR LACK THERE-OF SCREWING UP MIXTURE DISTRIBUTION WHILE KEEPING THE FUEL IN SUSPENSION INSIDE AN INTAKE MANIFOLD-CARB COMBO.
EFI MANIFOLDS DO NOT HAVE TO HAVE THIS IN CONSIDERATION BECAUSE THEIR MAIN CONCERN IS FLOWING EQUAL AMOUNTS OF AIR "ONLY"....
NEVER HAVING TO WORRY ABOUT FUEL DISTRIBUTION EQUALLY AMONG ALL THE INTAKE RUNNERS.
FUEL INJECTORS DISTRIBUTES PROPER AMOUNTS OF FUEL INDIVIDUALLY INTO THE PORTS MUCH BETTER THAN A CARBURETOR WILL EVER DO @ IDLE, CRUISE OR FULL THROTTLE.....
E.F.I. TURBO-SUPERCHARGER:
THERE IS NO DOUBT THAT TODAYS HIGH BOOST LEVELS ARE POSSIBLE WITH THE PRECISE METERING AND DISTRIBUTION OF THE FUEL INSIDE THE MANIFOLD COURTESY OF THE MODERN RACING EFI'S.
NOT POSSIBLE TO SAFELY DO IN THE PAST AND THIS WAS THE LIMITING FACTOR THAT PREVENTED HIGH BOOST TO BE SAFELY ACCOMPLISHED. (unequal fuel distribution has a disastrous effect )
SO CONSEQUENTLY POWER WENT UP WITH TODAYS MODERN ENGINES.
I AM SATISFIED WITH TURBO-EFI ENGINES AND ITS POWER.
HOWEVER, RECENTLY THERE IS A "NEW" OLD DOG IN TOWN....
SUPERCHARGER-CARBURETOR:
THIS HAS BEEN THE RAGE LATELY AND I MYSELF IS IN THIS BANDWAGON.
THIS PACKAGE EXHIBITED SUPERIOR RESPONSE AND OFF-THE LINE POWER AT THE TRACKS!
GRANTED TRACTION WAS GOOD COMPARED TO EFI TURBO....
I ATTRIBUTE THIS ADVANTAGE TO THE "COOLER" & "DENSER" INLET CHARGE TEMPERATURE EXHIBITED BY THE JOULE-THOMSON EFFECT. COOLER, DENSER MIXTURES INSIDE THE MANIFOLD I BELIEVE RESULTS IN ADDITIONAL POWER AGAINST ANY COMPARABLE EFI BOOST LEVELS.
This is even more obvious if no intercooler is used....
THE REDUCTION OF BOOST-LAG IN A SUPERCHARGER VS TURBO LAG RESPONSE TIME,
WITH THE JOULE-THOMSON CREATING COOLER/DENSER BOOST "QUALITY"
GIVES AN IMMEDIATE TORQUE ADVANTAGE OFF THE LINE & REQUIRES LESS INTERCOOLER!
FOR ANY REASON WHEN COMBINED WITH AN INTERCOOLER OF SIMILAR SIZE EQUALS MORE POWER AT THE SAME BOOST LEVELS !
IT SEEMS FOR NOW "MIXTURE DISTRIBUTION" INSIDE THE MANIFOLD PLENUM CAN BE A MAJOR CONCERN IF BOOSTED REAL HIGH.
A STRAIGHT AND HIGH PORT MANIFOLD LIKE THE ONE PICTURED HERE MIGHT MINIMIZE A/F SEPARATION ON A BOOSTED CARB. ENGINE....
( I will see when I push the boost on this new engine I am building...)
THERE ARE NEW HIGH TECH "SUPERCHARGE SPEC" CARBURETORS SOLD AND BUILT SPECIFICALLY FOR THIS USE.
IF IT HAS MET ITS BOOST LIMITS COMPARED TO WHERE MAXIMUM BOOST LEVELS ARE ON AN EFI-TURBO, I HAVE NOT SEEN IT YET AND THE POWER I SEE AT THE TRACK IS VERY VERY CLOSE!
WILL SEE THIS WHEN I START PUSHING THE BOOST LEVELS COMPARABLE TO EFI-TURBO LEVELS ???
I SINCERELY BELIEVE THAT IF YOU BOOST A CARB ENGINE TO ITS MAXIMUM, MIXTURE DISTRIBUTION TO ALL THE CYLINDERS WILL BECOME A PROBLEM.
NOTE:
THERE IS NO WAY YOU CAN PUSH AND AT THE SAME TIME MAKE THE HEAVIER FUEL MOLECULES TURN TOWARDS THE CYLINDER HEADS S FROM THE MANIFOLD PLENUM.
FUEL PARTICLES WILL NOT STAY HOMOGENOUS AT THIS POINT INSIDE THE RUNNERS.
************************************************************
RECENTLY AT IRWINDALE DRAGSTRIP, A FRIEND OF MINE WHO WILL REMAIN ANONYMOUS...
ELECTED TO USE ONE OF "2" MANIFOLDS
RE-WORKED BY ME AND RAN
5.10's @ 130+MPH 1/8 MILE PASS!
ON SMALL TIRES AND BASICALLY STOCK SUSPENSION.
BOOST LEVEL "LOW" COMPARED TO OTHER EFI ENGINES WE HAVE SEEN.
IF THIS CAR DECIDES TO RUN 8.5's IT CAN BE DOMINANT!
He foot brake off the line and was nowhere close to shocking or breaking traction..
**********************************************************
I AM EXCITED BY NEW CHALLENGES USING OLD SCHOOL CARBURETORS AND COMBINING THIS WITH HIGH TECH IGNITION CONTROLS ( MSD-DIGITAL) TO GET FURTHER INTO THE POWER CURVE!
DATA LOGGERS AND EGT SENSORS ARE USED AS ARE OTHERS.....
WITH THE SIMPLICITY OF A BOOSTED CARB., ULTIMATELY WITH "EXTREMELY HIGH" BOOST AND ON THE EDGE TUNING .
AN EFI ENGINE WILL PREVAIL!
THERE IS NO ROOM FOR ERROR....
DIFFERENCE BETWEEN TURBO-EFI VS SUPERCHARGE-CARB?
PRICE!
CHEAPER, MORE RELIABLE AND EASIER TO TUNE....
CARBS MUCH CHEAPER THAN EFI COMPUTERS >FAST, HALTECH, OTHERS....
BUT THERE ARE LIMITS TO CARBS.
ME ? A HUMAN COMPUTER....
JUST FEED ME AND I GO TO WORK!
LOL
TRACK TIPS:
I NOTICED LATELY THAT HIGH TECH EFI TUNERS RELY HEAVILY ON SCREEN INFORMATION. I STRONGLY RECOMMEND THAT THE OLD FASHIONED PLUG CHECK WILL SHOW THINGS HIGH TECH SCREEN INFO CANNOT DO.
THIS IS WHERE OLD SCHOOL CARB TUNERS HAVE AN ADVANTAGE AND THIS IS THE NORM FOR SHARP CARB. TUNERS.
BOTH HAVE SOMETHING TO LEARN FROM EACH OTHER AND IT IS BEST TO KNOW BOTH PROCESS....
I DID!
I am an old dog with new tricks! hehehe....
1. PLEASE REMEMBER THAT EVEN IF YOUR EFI READ OUT ON YOUR DISPLAY SCREEN SHOWS THE PROPER DESIRED AIR/FUEL MIXTURE?
TAKE TIME TO REMOVE AND "READ" THE SPARK PLUG COLOR TO VERIFY THE A/F RATIO. MANY "HIGH TECH" TUNERS MISS THIS COMPLETELY AND SOME OLD TECHNIQUES NEVER GET OLD....
THEY WILL CONSISTENTLY TELL YOU WHAT REALLY GOES INSIDE THE ENGINES COMBUSTION CHAMBERS THAT EGT'S CANNOT SEE....
This has been repeated many times @ the racetracks when I compare plug readings to computer readout.....seldom the same and I rely more on plug color. It is comparable to listening with a sthetoscope to your lung inhalations and I go inside and look at your lungs directly by X-ray.
Things that you may or may not hear but I can see... Plug check!
SOME OF US PULL THE PLUGS & THE LOOK AT THE HEDDER PIPES TO VERIFY THE BURN....
"MUST" TO VERIFY IF YOU ARE RUNNING EVERYTHING CLOSE TO THE EDGE!
Sometimes pulling the hedder pipes will show the presence of oil......?
rings? piston? cylinder walls? block oil control issues?
or just a tired & worn engine......plugs sometimes will not show this specially if your running exotic fuels that burn clean!
2. ALSO NOTE THAT YOUR DYNO TUNE WILL REQUIRE A LOT MORE FUEL @ THE TRACK BECAUSE THE "LOADING" FACTORS AND "DYNAMICS" ARE VERY DIFFERENT THAN A STATIONARY DYNO TEST.
3. IGNITION TIMING REQUIREMENTS WILL ALSO CHANGE AND SOME BUT NOT ALL LIKES A LITTLE BIT MORE TIMING THAN WHAT THE EFI TELLS YOU @ THE TRACK VS. @ THE DYNO. THIS IS EVIDENT ON THE LOWER GEARS AND INCREASING THE IGNITION CURVE ON THE LOWER GEAR RANGES WILL PROBABLY YIELD POSITIVE RESULTS. AND SOME WILL WANT LESS TIMING @ THE TOP GEAR PULL.
THE EXCEPTION IS IF THE ENGINE BOGS DOWN AND THE FIX OR LOCKED TIMING SETTING WILL BE DISASTROUS TO YOUR ENGINE AND HERE BACKING DOWN THE TIMING REQUIREMENTS WILL BE ADVISABLE TO PREVENT DETONATION @ THE LOWER RPM RANGE.
CARB. RACERS NEED TO DO THIS TOO!
BECAUSE A CARB IS A "DUMB" PIECE OF EQUIPTMENT.
IT IS ONLY AS GOOD AND AS SMART AS YOU ARE CAPABLE OF....
REMEMBER YOU ARE ITS (EFI) COMPUTER!
( Exceptional, Focused & Intelligent....lol )
+++++++++++++++++++++++++++++++++++++++
REVERSE DIRECTION INJECTORS?
AT THE LAST ENGINE MASTERS COMPETITION,
EVENTUAL WINNER JON KAASE EMPLOYED REVERSE DIRECTION FUEL INJECTORS!
THE PURPOSE TO INJECT THE SPRAY PATTERN OPPOSITE THE FLOW DIRECTION!
IN FACT WHAT IT ESSENTIALLY DID WAS BLAST THE SPRAY PATTERN STRAIGHT AGAINST THE INCOMING AIR CHARGE!
THERE IS ALSO EVIDENCE OF THE SPRAY PATTERN INSIDE THE ROOF OF THE MANIFOLD PLENUM.
IT MAY HAVE BEEN HIS ATTEMPT AT COOLING THE INCOMING INTAKE AIR CHARGE COLUMN.
GIVING IT TIME TO APPLY THE THOMAS- JOULE EFFECT IN AN EFI ENGINE!
IN THIS INSTANCE , HE SACRIFICED IDEAL A/F DISTRIBUTION AROUND THE MANIFOLD FOR COOLING.....
IT WORK AND WON THE COMPETITION.
WHO IS GOING TO ARGUE WITH THAT?
PLEASE, CHECK ENGINE MASTERS COMPETITION MAGAZINE FOR PICTURES ON THIS ENGINE AND ITS INJECTOR POSITIONING.
TITLED: JON KAASE MODULAR MOTOR!
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
TO KEEP IT STRAIGHT....
RACE THE TRACK NOT THE DYNO!
.....
BEN ALAMEDA @ PARA TECH. FB, BENALAMEDARACING.COM
Tech in memory of friend & mentor Charles DC Stevens.....
THERE ARE A LOT OF DISCUSSIONS ON WHICH IS BETTER AND I AM SURE I WILL ADD FUEL TO THE FIRE!
OPINIONS WITHSTANDING, I WILL BASE IT ON WHAT I SEE AT THE RACETRACKS AND NOT WHAT OTHERS TELL ME OR WHAT I HAVE HEARD.......
EXPERIENCE BUILDING BOTH GIVES ME AN INVALUABLE DATA THAT I CAN PUT TOGETHER GIVING AN HONEST OPINION ON THE ADVANTAGES AND DISADVANTAGES OF EITHER ONE.
ELECTRONIC FUEL INJECTION TODAY ARE HIGH TECHNOLOGY PROVIDING CONSISTENT AIR/FUEL RATIO ACROSS THE RPM RANGE.
"ACURACY IN AIR/FUEL RATIOS" GIVES IT AN EDGE IN THE TUNING WINDOW UNATTAINED BEFORE WITH MECHANICAL FUEL INJECTION OR A CARBURETOR.
CARBURETORS MEANWHILE ARE LOW TECH AND DUMB!
CRUDE AND ANCIENT COMPAIRED TO
COMPUTER CONTROLLED E.F.I.
MEANWHILE SOME RACING CARBS TODAY COME WITH NEW "HIGH TECH VENTURIS" AND METERING BLOCKS.
HOWEVER IT NEEDS A COMPETENT TUNER TO GET MOST OUT OF THIS COMBINATION.
ADJUSTMENTS HAS TO BE INTERPRETED BY THE TUNER WHEREAS COMPUTERIZE F.I. GIVES FEEDBACK FROM SENSORS AND THE DISPLAY SCREEN.
HOWEVER, THE E.F.I. TUNER HAS TO BE ON TOP OF HIS GAME AND MAKE THE PROPER ADJUSTMENTS.
IF HE IS INCOMPETENT IN HIS CRAFT?
THEN HIGH TECH HAS NO ADVANTAGE WHATSOEVER!
EFI DELIVERS CONSISTENT AIR/FUEL MIXTURES "ALL" THE TIME AS PROGRAMMED.
CARBS CAN ALSO DELIVER A CONSISTENT AIR/FUEL BUT ONLY "MOST" OF THE TIME.
HOWEVER! RECENT HIGH TECH RACING CARBS CAN GIVE AN EFI A RUN FOR ITS MONEY....
SO WHERE IS THE DIFFERENCE?
IT IS IN THE "EMULSIFIED" AND "ATOMIZED" CONDITION OF THE AIR/FUEL MIXTURE INSIDE THE INTAKE PORTS!
A CONDITION PERMITING FASTER BUILD-UP OF THE RPM'S RESULTING IN +5-6% MORE HORSEPOWER OVER EFI. CONSIDERING ALL PERIMETERS ARE EQUAL.
JOULE-THOMSON EFFECT:
ANOTHER ADVANTAGE FEW PEOPLE KNOW IS THE "JOULE-THOMSON" EFFECT THAT DECREASES INLET TEMPERATURES OF THE AIR/FUEL MIXTURE BY AT LEAST 20* DEGREES!
THIS MEANS THAT COMPARING EFI VS. CARB CARB. ENGINES SEES FOR EXAMPLE> AN 80*F DEGREE INTAKE TEMPERATURE.....
MEANWHILE AN EFI WILL BE RUNNING AT APPROXIMATELY 100*F OR MORE!
AN ADVANTAGE THAT IS VERY HARD TO OVERCOME IN ANY COMPETITION ALBEIT A CLOSE ONE!
CARB. INTAKES PROVIDES DENSER, COOLER & "FUEL-MISTED" MIXTURE QUALITY.
ALLOWS MORE HORSEPOWER COMPARED TO A "DRY" & "HOT" EFI INTAKE MANIFOLD.
( This drop in inlet temp. is caused by the J-T effect when the fuel droplets are discharge below the venture. Causing an immediate "drop" in temperatures.
You can test this theory by running your air compressor till it is hot @ the tank & lines.
Using a nozzle while pressing the trigger,
note the temperature. of the exiting air past the nozzles...?
it will be much cooler than the air in the pressure line/tank!
This is the J-T effect!
Introducing a "small amount of water spray" also adds to the cooling much like fuel stream/small droplets being discharge directly at the bottom of a carb ).
THE EXPLANATION ABOVE HAS BEEN PROVEN SEVERAL TIMES WHEN I SWITCHED FROM EFI TO CARBS OR VICE VERSA.
THE IMMEDIATE COMMENT IS THE CARBS RPM RISE IS MUCH QUICKER ACROSS THE RPM RANGE AND THE RESPONSE IS MUCH BETTER!
E.F.I. ADVANTAGES:
CARB. ENGINES HAS LESS "TORQUE" DOWN LOW AND THIS IS WHERE EFI EXCELS
THE SUPERIORITY OF CONSISTENT DISTRIBUTION OF FUEL INSIDE THE INTAKE MANIFOLDS ON THE LOW-MID-HIGH RPM RANGES CANNOT BE DISMISSED.
E.F.I. INTAKE RUNNER LENGTH:
ANOTHER ASPECT IS THE LONG INTAKE MANIFOLD RUNNERS ON EFI COMPARED TO CARBS.
"RAM INDUCTION" OR RAM TUNING ON EFI MANIFOLDS INCREASES VOLUMETRIC EFFICIENCY OR WHAT IS CALLED CYLINDER FILLING BY A SIGNIFICANT MARGIN.
BOOSTING TORQUE UNHEARD OR UNSEEN IN CARB ENGINES.
SPECIALLY IF THE "LENGTH IS TUNED" TO A SPECIFIC RPM RANGE AND IT WILL OUTPULL JUST ABOUT ANY CARB ENGINE ANYWHERE!
EFI DISADVANTAGES:
THE DRAWBACK IS, LONG RUNNER LENGTHS CREATES "PUMPING LOSSES" THAT KILLS HORSEPOWER DUE ADDED INTAKE RESTRICTIONS ASSOCIATED WITH LONG PORTS.
MOST CARB MANIFOLDS ARE GENERALLY SHORTER IN LENGTH AND THEREFORE MORE HIGH RPM ORIENTED THAN THE TYPICAL EFI MANIFOLDS. HENCE THEY HAVE LESS PUMPING LOSS AT ELEVATED ENGINE SPEEDS.
MY EXPERIENCE AT DRAGSTRIPS WITH MOTORCYCLES OR CARS,
CARBS WINS HANDS DOWN....
FASTER ALL ELSE BEING EQUAL!
ON THE OFF-ROAD OR HILL CLIMB RACERS?
THE EFI WINS DECISIVELY!
(Sometimes exception are on high speed off-road courses )
EFI'S ARE NOT AFFECTED AS EASILY AS A CARB ENGINE AT DIFFICULT ANGLES >
CLIMBING OR DESCENDING.....
CARBS ALSO GETS AFFECTED AND LOOSES "FLOAT LEVEL CONTROL" WHEN OFF-ROAD TRUCKS GET "AIRBORNE" OR SPECIALLY ON THE WHOOPSIE DOOS.
( several big n small fast jumps one after the other )
IT FLOODS EVEN WHEN USING BOWL EXTENSIONS, BAFFLES, VENT TUBES AND OR "CATHEDRAL" TYPE FLOATS.
I GET COMPLAINTS FROM SEVERAL OF MY OFF-ROAD CUSTOMERS SWITCHING TO EFI FROM CARBS BECAUSE OF THIS DILEMMA.
LAST BUT NOT LEAST DUST AND DIRT HAVE A DISASTROUS EFFECT ON THE CARBS METERING ABILITIES WHEN AIR BLEEDS ARE BLOCKED BY DIRT PARTICLES.
THEREFORE SUPERIOR AIR FILTRATION IS A MUST HAVE.
EFI ONLY DRAWBACK HERE IS ITS NEED FOR A CLEAN FUEL FILTER AND A GOOD AIR CLEANER ASSEMBLY.
ON ROAD- RACE ENGINES, THE HIGHER "G" FORCES AT THE CORNERS? THE BETTER EFI'S ADVANTAGES.
AT THIS POINT THE CARBS HORSEPOWER ADVANTAGE IS LESSENED IF IT STUMBLES AND SURGES FROM A CORNER OR INTO A CORNER STARTING TO STALL....
HOWEVER ADVANCES IN VENTURI AND METERING BY SOME ALL OUT RACING CARB MANUFACTURERS MAKES THIS AN ALMOST NON- EXISTENT PROBLEM.
I ALSO WITHHOLD COMMENTS UNTIL I SEE AN F-1 OR INDY CAR RUN A CARBURETOR ON A VERY DEMANDING ROAD COURSE......
I KNOW ELEVATED "G"-FORCES ON CORNERS WILL KILL A CARBURETOR!
( As a side note... Aircraft like the German Lufwaffe Me-109 fighter came with Daimler-Benz (Mercedes Benz) fuel-injection on their engines. Contrary against Allied British Spitfire's "carbureted" fighter engines of WW-2 era.
The British planes will surge and stall out every time the Germans pull a negative "G" maneuver to get away from the British fighters and other prolonged or sustained maneuvers....Advantage F.I. ! LOL ).
EFI'S BIG ADVANTAGE IN MILEAGE & EMISSIONS:
SUPERIOR AND CONSISTENT FUEL MIXURE INSIDE THE INTAKE PORTS YIELDS BETTER MILEAGE AND EMISSION COMPLIANCE.
CARBURETORS CRUDE MIXING ABILITY TAKES A BACK SEAT TO EFI'S.
MODIFIED BOOSTER VENTURIS HOWEVER CAN ONLY DO SO MUCH.
BECAUSE, WHEN FUEL DISCHARGES BELOW THE VENTURIS/THROTTLE PLATES IN A MANIFOLD PLENUM?
PROPER FUEL- DISTRIBUTION IS AT THE "MERCY" OF THE MANIFOLD DESIGN!
IT HAS TO BE ABLE TO FLOW SIMILAR/EQUAL AMOUNTS OF FUEL MIX ON ALL THE PORTS WHILE KEEPING THE A/F MIXTURE IN SUSPENSION.
ANOTHER IMPORTANT FACTOR IS HEAT OR LACK THERE-OF SCREWING UP MIXTURE DISTRIBUTION WHILE KEEPING THE FUEL IN SUSPENSION INSIDE AN INTAKE MANIFOLD-CARB COMBO.
EFI MANIFOLDS DO NOT HAVE TO HAVE THIS IN CONSIDERATION BECAUSE THEIR MAIN CONCERN IS FLOWING EQUAL AMOUNTS OF AIR "ONLY"....
NEVER HAVING TO WORRY ABOUT FUEL DISTRIBUTION EQUALLY AMONG ALL THE INTAKE RUNNERS.
FUEL INJECTORS DISTRIBUTES PROPER AMOUNTS OF FUEL INDIVIDUALLY INTO THE PORTS MUCH BETTER THAN A CARBURETOR WILL EVER DO @ IDLE, CRUISE OR FULL THROTTLE.....
E.F.I. TURBO-SUPERCHARGER:
THERE IS NO DOUBT THAT TODAYS HIGH BOOST LEVELS ARE POSSIBLE WITH THE PRECISE METERING AND DISTRIBUTION OF THE FUEL INSIDE THE MANIFOLD COURTESY OF THE MODERN RACING EFI'S.
NOT POSSIBLE TO SAFELY DO IN THE PAST AND THIS WAS THE LIMITING FACTOR THAT PREVENTED HIGH BOOST TO BE SAFELY ACCOMPLISHED. (unequal fuel distribution has a disastrous effect )
SO CONSEQUENTLY POWER WENT UP WITH TODAYS MODERN ENGINES.
I AM SATISFIED WITH TURBO-EFI ENGINES AND ITS POWER.
HOWEVER, RECENTLY THERE IS A "NEW" OLD DOG IN TOWN....
SUPERCHARGER-CARBURETOR:
THIS HAS BEEN THE RAGE LATELY AND I MYSELF IS IN THIS BANDWAGON.
THIS PACKAGE EXHIBITED SUPERIOR RESPONSE AND OFF-THE LINE POWER AT THE TRACKS!
GRANTED TRACTION WAS GOOD COMPARED TO EFI TURBO....
I ATTRIBUTE THIS ADVANTAGE TO THE "COOLER" & "DENSER" INLET CHARGE TEMPERATURE EXHIBITED BY THE JOULE-THOMSON EFFECT. COOLER, DENSER MIXTURES INSIDE THE MANIFOLD I BELIEVE RESULTS IN ADDITIONAL POWER AGAINST ANY COMPARABLE EFI BOOST LEVELS.
This is even more obvious if no intercooler is used....
THE REDUCTION OF BOOST-LAG IN A SUPERCHARGER VS TURBO LAG RESPONSE TIME,
WITH THE JOULE-THOMSON CREATING COOLER/DENSER BOOST "QUALITY"
GIVES AN IMMEDIATE TORQUE ADVANTAGE OFF THE LINE & REQUIRES LESS INTERCOOLER!
FOR ANY REASON WHEN COMBINED WITH AN INTERCOOLER OF SIMILAR SIZE EQUALS MORE POWER AT THE SAME BOOST LEVELS !
IT SEEMS FOR NOW "MIXTURE DISTRIBUTION" INSIDE THE MANIFOLD PLENUM CAN BE A MAJOR CONCERN IF BOOSTED REAL HIGH.
A STRAIGHT AND HIGH PORT MANIFOLD LIKE THE ONE PICTURED HERE MIGHT MINIMIZE A/F SEPARATION ON A BOOSTED CARB. ENGINE....
( I will see when I push the boost on this new engine I am building...)
THERE ARE NEW HIGH TECH "SUPERCHARGE SPEC" CARBURETORS SOLD AND BUILT SPECIFICALLY FOR THIS USE.
IF IT HAS MET ITS BOOST LIMITS COMPARED TO WHERE MAXIMUM BOOST LEVELS ARE ON AN EFI-TURBO, I HAVE NOT SEEN IT YET AND THE POWER I SEE AT THE TRACK IS VERY VERY CLOSE!
WILL SEE THIS WHEN I START PUSHING THE BOOST LEVELS COMPARABLE TO EFI-TURBO LEVELS ???
I SINCERELY BELIEVE THAT IF YOU BOOST A CARB ENGINE TO ITS MAXIMUM, MIXTURE DISTRIBUTION TO ALL THE CYLINDERS WILL BECOME A PROBLEM.
NOTE:
THERE IS NO WAY YOU CAN PUSH AND AT THE SAME TIME MAKE THE HEAVIER FUEL MOLECULES TURN TOWARDS THE CYLINDER HEADS S FROM THE MANIFOLD PLENUM.
FUEL PARTICLES WILL NOT STAY HOMOGENOUS AT THIS POINT INSIDE THE RUNNERS.
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RECENTLY AT IRWINDALE DRAGSTRIP, A FRIEND OF MINE WHO WILL REMAIN ANONYMOUS...
ELECTED TO USE ONE OF "2" MANIFOLDS
RE-WORKED BY ME AND RAN
5.10's @ 130+MPH 1/8 MILE PASS!
ON SMALL TIRES AND BASICALLY STOCK SUSPENSION.
BOOST LEVEL "LOW" COMPARED TO OTHER EFI ENGINES WE HAVE SEEN.
IF THIS CAR DECIDES TO RUN 8.5's IT CAN BE DOMINANT!
He foot brake off the line and was nowhere close to shocking or breaking traction..
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I AM EXCITED BY NEW CHALLENGES USING OLD SCHOOL CARBURETORS AND COMBINING THIS WITH HIGH TECH IGNITION CONTROLS ( MSD-DIGITAL) TO GET FURTHER INTO THE POWER CURVE!
DATA LOGGERS AND EGT SENSORS ARE USED AS ARE OTHERS.....
WITH THE SIMPLICITY OF A BOOSTED CARB., ULTIMATELY WITH "EXTREMELY HIGH" BOOST AND ON THE EDGE TUNING .
AN EFI ENGINE WILL PREVAIL!
THERE IS NO ROOM FOR ERROR....
DIFFERENCE BETWEEN TURBO-EFI VS SUPERCHARGE-CARB?
PRICE!
CHEAPER, MORE RELIABLE AND EASIER TO TUNE....
CARBS MUCH CHEAPER THAN EFI COMPUTERS >FAST, HALTECH, OTHERS....
BUT THERE ARE LIMITS TO CARBS.
ME ? A HUMAN COMPUTER....
JUST FEED ME AND I GO TO WORK!
LOL
TRACK TIPS:
I NOTICED LATELY THAT HIGH TECH EFI TUNERS RELY HEAVILY ON SCREEN INFORMATION. I STRONGLY RECOMMEND THAT THE OLD FASHIONED PLUG CHECK WILL SHOW THINGS HIGH TECH SCREEN INFO CANNOT DO.
THIS IS WHERE OLD SCHOOL CARB TUNERS HAVE AN ADVANTAGE AND THIS IS THE NORM FOR SHARP CARB. TUNERS.
BOTH HAVE SOMETHING TO LEARN FROM EACH OTHER AND IT IS BEST TO KNOW BOTH PROCESS....
I DID!
I am an old dog with new tricks! hehehe....
1. PLEASE REMEMBER THAT EVEN IF YOUR EFI READ OUT ON YOUR DISPLAY SCREEN SHOWS THE PROPER DESIRED AIR/FUEL MIXTURE?
TAKE TIME TO REMOVE AND "READ" THE SPARK PLUG COLOR TO VERIFY THE A/F RATIO. MANY "HIGH TECH" TUNERS MISS THIS COMPLETELY AND SOME OLD TECHNIQUES NEVER GET OLD....
THEY WILL CONSISTENTLY TELL YOU WHAT REALLY GOES INSIDE THE ENGINES COMBUSTION CHAMBERS THAT EGT'S CANNOT SEE....
This has been repeated many times @ the racetracks when I compare plug readings to computer readout.....seldom the same and I rely more on plug color. It is comparable to listening with a sthetoscope to your lung inhalations and I go inside and look at your lungs directly by X-ray.
Things that you may or may not hear but I can see... Plug check!
SOME OF US PULL THE PLUGS & THE LOOK AT THE HEDDER PIPES TO VERIFY THE BURN....
"MUST" TO VERIFY IF YOU ARE RUNNING EVERYTHING CLOSE TO THE EDGE!
Sometimes pulling the hedder pipes will show the presence of oil......?
rings? piston? cylinder walls? block oil control issues?
or just a tired & worn engine......plugs sometimes will not show this specially if your running exotic fuels that burn clean!
2. ALSO NOTE THAT YOUR DYNO TUNE WILL REQUIRE A LOT MORE FUEL @ THE TRACK BECAUSE THE "LOADING" FACTORS AND "DYNAMICS" ARE VERY DIFFERENT THAN A STATIONARY DYNO TEST.
3. IGNITION TIMING REQUIREMENTS WILL ALSO CHANGE AND SOME BUT NOT ALL LIKES A LITTLE BIT MORE TIMING THAN WHAT THE EFI TELLS YOU @ THE TRACK VS. @ THE DYNO. THIS IS EVIDENT ON THE LOWER GEARS AND INCREASING THE IGNITION CURVE ON THE LOWER GEAR RANGES WILL PROBABLY YIELD POSITIVE RESULTS. AND SOME WILL WANT LESS TIMING @ THE TOP GEAR PULL.
THE EXCEPTION IS IF THE ENGINE BOGS DOWN AND THE FIX OR LOCKED TIMING SETTING WILL BE DISASTROUS TO YOUR ENGINE AND HERE BACKING DOWN THE TIMING REQUIREMENTS WILL BE ADVISABLE TO PREVENT DETONATION @ THE LOWER RPM RANGE.
CARB. RACERS NEED TO DO THIS TOO!
BECAUSE A CARB IS A "DUMB" PIECE OF EQUIPTMENT.
IT IS ONLY AS GOOD AND AS SMART AS YOU ARE CAPABLE OF....
REMEMBER YOU ARE ITS (EFI) COMPUTER!
( Exceptional, Focused & Intelligent....lol )
+++++++++++++++++++++++++++++++++++++++
REVERSE DIRECTION INJECTORS?
AT THE LAST ENGINE MASTERS COMPETITION,
EVENTUAL WINNER JON KAASE EMPLOYED REVERSE DIRECTION FUEL INJECTORS!
THE PURPOSE TO INJECT THE SPRAY PATTERN OPPOSITE THE FLOW DIRECTION!
IN FACT WHAT IT ESSENTIALLY DID WAS BLAST THE SPRAY PATTERN STRAIGHT AGAINST THE INCOMING AIR CHARGE!
THERE IS ALSO EVIDENCE OF THE SPRAY PATTERN INSIDE THE ROOF OF THE MANIFOLD PLENUM.
IT MAY HAVE BEEN HIS ATTEMPT AT COOLING THE INCOMING INTAKE AIR CHARGE COLUMN.
GIVING IT TIME TO APPLY THE THOMAS- JOULE EFFECT IN AN EFI ENGINE!
IN THIS INSTANCE , HE SACRIFICED IDEAL A/F DISTRIBUTION AROUND THE MANIFOLD FOR COOLING.....
IT WORK AND WON THE COMPETITION.
WHO IS GOING TO ARGUE WITH THAT?
PLEASE, CHECK ENGINE MASTERS COMPETITION MAGAZINE FOR PICTURES ON THIS ENGINE AND ITS INJECTOR POSITIONING.
TITLED: JON KAASE MODULAR MOTOR!
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
TO KEEP IT STRAIGHT....
RACE THE TRACK NOT THE DYNO!
.....
BEN ALAMEDA @ PARA TECH. FB, BENALAMEDARACING.COM
Tech in memory of friend & mentor Charles DC Stevens.....
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