Rivals Automotive Performance
Expanding the Worlds Automotive Knowledge
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Manifold Design
LOG TYPE MANIFOLDS
​THESE EXHAUST MANIFOLDS OR HEADERS ARE USUALLY MADE FROM CAST IRON, ARE EXTREMELY HEAVY, HEAT RESISTANT, AMD CHEAPLY DESIGNED.
THESE ARE THE MANIFOLDS THAT USUALLY COME STOCK ON A CAR, AND ARE YOUR BENCHMARK FOR ALL POWER GAINS.
YOU ARE UNLIKELY TO FIND ANY LESSER PERFORMING OPTIONS FOR SALE.
TUBULAR HEADERS
THIS IS A GENERAL SUB-CLASSIFICATION OF EXHAUST MANIFOLD DESIGN.
THESE WILL BE CONSTRUCTED FROM ROUND OR OVAL PIPES AND BENT INTO A SHAPE TO FLOW EXHAUST FROM THE HEADS TO THE MIDPIPE, BUT SIZE AND LENGTH ARE VARIABLE.
TYPICALLY THEY WILL HAVE AN O2 SENSOR LOCATION FOR GETTING AIR-FUEL RATIOS (AFRs)
LONG TUBE HEADERS
THESE ARE TYPICALLY THE BEST OPTION FOR NATURALLY ASPIRATED ENGINES THAT ARE LOOKING FOR TOP-END POWER, LIKE RACING.
DUE TO THEIR LENGTH, THEY TYPICALLY REQUIRE A NEW MIDPIPE AND REMOVE THE CATALYTIC CONVERTERS.
EACH CYLINDER EXHAUST WILL TRAVEL THE FULL LENGTH OF THE TUBE UNINTERUPTED BEFORE THEN MERGING WITH OTHERS.
THE ADDITIONAL LENGTH HELPS TO SMOOTH OUT THE TURBULANCE AND INCREASE THE EFFECTIVE SCAVENGING FOR EACH CYLINDER TOWARD THE TOP END OF THE POWER RANGE.
THESE DONT TYPICALLY HURT LOW-MID RANGE TORQUE BUT WILL MAKE LESS THAN OTHER AFTERMARKET OPTIONS.
THE COLLECTION SET UP FOR LONG TUBES CAN VARRY, 4-1 3-1 AND 2-1 COLLECT ALL PIPES TOGETHER AT THE SAME POINT, BUT 4-2-1 HEADERS WILL MERGE 4 PIPES INTO 2 BEFORE GOING TO 1 PIPE.
THE TWO EXTRA COLLECTORS CAN HELP TO INCREASE THE SCAVENGING EFFECT BUT THE CHANGE IS NOT ALWAYS NOTICIBLE..
SHORTY HEADERS
THESE ARE TYPICALLY THE BEST OPTION FOR DAILY DRIVERS AND STREET CARS.
THEY WILL USUALLY TAKE THE PLACE OF YOUR STOCK EXHAUST MANIFOLD AND BOLT UP TO YOUR EXISTING EXHAUST.
WITH THIS OPTION YOU CAN KEEP THE ORIGINAL MIDPIPE AND CATALYTIC CONVERTERS IF NEEDED FOR SMOG.
THE PIPES WILL BE A TUNED LEGTH SIMILAR TO THE STYLE OF LONG TUBE HEADERS, BUT THE SHORTER PIPE LENGTH WILL LEAD TO A POWER BOOST IN THE MID-RANGE OF THE ENGINE.
THIS WILL HELP DRIVERS FEEL THE ENGINE WHILE DOING NORMAL DRIVING WITHOUT BEING WIDE OPEN THROTTLE.
EQUAL LENGTH VS UNEQUAL LENGTH
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THIS IS USUALLY A QUESTION FOR THE BOXER COMMUNITY, BUT CAN BE APPLIED TO AND TYPE OF HEADER.
EQUAL LENGTH WILL GIVE YOU THE SMOOTHEST SOUNDING EXHAUST AND THE MOST POWER.
UNEQUAL LENGTH HEAEDERS WILL GIVE A MORE RUMBLING SOUND LIKE AN CROSS PLANE V8, BUT POWER WILL BE DECREASED AND WILL HAVE PEAKS AS SCAVINGING TIMING IS COMPROMISED.