in the sept 2008 chevy high performance magazine they did an intake/cam test,on a sbc 383 with 10.5:1 cpr and brodix IK200cc heads and a couple of comp cams solid roller cams and a 750cfm holley carb, keep in mind the single plane intakes used a more radical cam than the dual planes were tested with, and the engine combo they used is unlikely to match your so the results on your combo are sure to differ, but its still rather interesting to see the differences an intake makes
, BTW they DID test the EDELBROCK DUAL PLANE intake with the larger cam, that the single planes were tested with and and the EDELBROCK single plane with the smaller cam the dual planes were tested with
Chevy high performance mags sbc intake test
1969 3932472 302 4 al Holley Z-28, F, Hirise
1967-68 3917610 302 4 al Holley Z-28, F, hirise
be aware that matching your exhaust system header scavenging and cam timing , and reducing your exhaust system flow restriction,has a great deal to do with how well your intake manifold potentially flows, at its most efficient rpm band, gains of 50-60 ft lbs of torque,(or in some cases much more) over what the stock engine made have frequently been seen when properly matched cam timing, header scavenging and intake design are well matched
Id also point out that cam timing matched to the exhaust scavenging has a huge effect on potential intake flow rates
http://www.hotrod.com/how-to/engine/113-0407-best-induction-combo/
BTW READ THIS ALSO
yeah! I know youll want to ignore the sub links, but theres a ton of charts and related info you need so ignoring the data is not helping you
http://www.popularhotrodding.com/engine ... index.html
video
http://www.hotrod.com/how-to/engine/130 ... mparisons/
http://www.racingheadservice.com/rhs/in ... -chevyhtml
Dual planes
BRAND...............¦Torque.........rpm........hp..........rpm
Brodix-hv101........471...............3900......437.........5500
Dart.42811000......482...............3900.......43...........5400
Edelbrock
Rpm air gap..7501..485..............3900.......441.........5600
BIG CAM test.........494......4200..........509.......6200
Professional prod
Crosswind.............482...........3800........430........5500
Summit-226010.......487...........3800........430.........5800
Weiand 8501.........489...........3800.........433.........5600
Chevy z28
/327/365hp intake..468............3800........¦417........5600
Single planes
BRAND.............Torque.............rpm......hp...........rpm
Brodix hv1011..472...................5100......492..........6200
Dart..42411000..479..................5100.......512...........6400
Edelbrock
vic jr..2975.......477.................5100........500.........6100
EDELBROCK
SMALL CAM....466...................3800..........448..........5600
edelbrock
super vic.....476...................4900............507.........6400
GM performance
10051102.......484..................5200...........515...........6300
HOLLEY KD
300-110..........478.................5100...........509...........6300
Pro..prod
Hurricane.......478................4900...........509............6200
Weiand
team.............478................5200..............507...........6100
world prod.....483................5000.............512............6300
NOTICE HOW THE LARGE CAM DUAL PLANE, COMBO DID VERY WELL
the basic rule is a dual plane intake will almost always be the better choice over a single plane intake if the cam duration is under about 235-240 degrees@.050 lift
http://www.chevyhiperformance.com/techa ... 0_cfm.html
if you read thru the link above, very carefully youll find the 750cfm -to 830cfm carbs made the best average power, on that 383 sbc, so if we average the results lets say an 800cfm might have been near ideal.
now you might think.... ok,
800cfm/383 cubic inches =2.09 cfm per cubic inch of displacement,
so logically a 454 big block x 2.09=948cfm.....,
or a 327 x 2.09= 683 cfm,
but the truth here is that a skilled and experienced engine tuner can get a 950cfm or a 750cfm carb to work remarkably well on either the 383 0r 454 engine.
that 2.09 cfm per cubic inch of engine displacement will get you "in the ball park" but its your ability to tune the carburetor to match the application , far more than the rated carb size thats much more critical to matching the carb to the engine.
READ THIS AND ITS SUB LINKED INFO
http://www.airflowresearch.com/articles ... 5/A-P1.htm
, BTW they DID test the EDELBROCK DUAL PLANE intake with the larger cam, that the single planes were tested with and and the EDELBROCK single plane with the smaller cam the dual planes were tested with
Chevy high performance mags sbc intake test
1969 3932472 302 4 al Holley Z-28, F, Hirise
1967-68 3917610 302 4 al Holley Z-28, F, hirise
be aware that matching your exhaust system header scavenging and cam timing , and reducing your exhaust system flow restriction,has a great deal to do with how well your intake manifold potentially flows, at its most efficient rpm band, gains of 50-60 ft lbs of torque,(or in some cases much more) over what the stock engine made have frequently been seen when properly matched cam timing, header scavenging and intake design are well matched
Id also point out that cam timing matched to the exhaust scavenging has a huge effect on potential intake flow rates
http://www.hotrod.com/how-to/engine/113-0407-best-induction-combo/
BTW READ THIS ALSO
yeah! I know youll want to ignore the sub links, but theres a ton of charts and related info you need so ignoring the data is not helping you
http://www.popularhotrodding.com/engine ... index.html
video
http://www.hotrod.com/how-to/engine/130 ... mparisons/
http://www.racingheadservice.com/rhs/in ... -chevyhtml
Dual planes
BRAND...............¦Torque.........rpm........hp..........rpm
Brodix-hv101........471...............3900......437.........5500
Dart.42811000......482...............3900.......43...........5400
Edelbrock
Rpm air gap..7501..485..............3900.......441.........5600
BIG CAM test.........494......4200..........509.......6200
Professional prod
Crosswind.............482...........3800........430........5500
Summit-226010.......487...........3800........430.........5800
Weiand 8501.........489...........3800.........433.........5600
Chevy z28
/327/365hp intake..468............3800........¦417........5600
Single planes
BRAND.............Torque.............rpm......hp...........rpm
Brodix hv1011..472...................5100......492..........6200
Dart..42411000..479..................5100.......512...........6400
Edelbrock
vic jr..2975.......477.................5100........500.........6100
EDELBROCK
SMALL CAM....466...................3800..........448..........5600
edelbrock
super vic.....476...................4900............507.........6400
GM performance
10051102.......484..................5200...........515...........6300
HOLLEY KD
300-110..........478.................5100...........509...........6300
Pro..prod
Hurricane.......478................4900...........509............6200
Weiand
team.............478................5200..............507...........6100
world prod.....483................5000.............512............6300
NOTICE HOW THE LARGE CAM DUAL PLANE, COMBO DID VERY WELL
the basic rule is a dual plane intake will almost always be the better choice over a single plane intake if the cam duration is under about 235-240 degrees@.050 lift
http://www.chevyhiperformance.com/techa ... 0_cfm.html
if you read thru the link above, very carefully youll find the 750cfm -to 830cfm carbs made the best average power, on that 383 sbc, so if we average the results lets say an 800cfm might have been near ideal.
now you might think.... ok,
800cfm/383 cubic inches =2.09 cfm per cubic inch of displacement,
so logically a 454 big block x 2.09=948cfm.....,
or a 327 x 2.09= 683 cfm,
but the truth here is that a skilled and experienced engine tuner can get a 950cfm or a 750cfm carb to work remarkably well on either the 383 0r 454 engine.
that 2.09 cfm per cubic inch of engine displacement will get you "in the ball park" but its your ability to tune the carburetor to match the application , far more than the rated carb size thats much more critical to matching the carb to the engine.
READ THIS AND ITS SUB LINKED INFO
http://www.airflowresearch.com/articles ... 5/A-P1.htm
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