i've personaaly never given any consideration to the orientation of the roosters tail. If the Australian and Japanese concept of shoving a carbs throttles 90 degrees to an Inline 4 or 6 cylinders crank upset power delivery, then why did 2-bbl Hemi Pacers eclipse 4-bbl AVS Chryslers on the race tracks of Australia. Or how come every 2 or 4-bbl intake Cain or Torco or Redline intake worked better with a non parallel thottle? Full starvation was an epidemic of any in line 4 or 6 cylinder ColtDatMazToy or FalcoHoldeRambValiant. Every one of them suffered fuel starvation in turns as the old humps leaned 7 degrees in turns, and even more in compitetion environments when the suspesion was stiffened. I am of the opinion that parallel to crank thottles are a great idea if possible, but plenty of dual quad V8's run ballistic performance off 4150 series carbs aligned front to back. NASCAR's love to make great power with just one 4150 series carb and fuel distribution isn't a problem. 650 hp at 7500 rpm from just 355 cubes proves that non IR systems can yieild huge power.
Independent runner venturi to peak power rpm optimisation is 99% of getting great power and wide based torque. The rest is mearly detail which could be undone by a simple air cleaner or missplaced silencer or resonator box. Similiar to how an effective optimised exhast could be totally undone by one deviation from the as dynoed ideal.
For me, the variables Vi and Ced and Xa define the nature of the intakes abilty to optimise or limit fuel standoff after a basic combination has been ratifed. See below.
Primarily, before discussing those three basic geometric design parameters above, your always stuck with a basic form to test, and then optimise, for in engine development, you always use horse trade from the existing base to the evolutionary optimum. In terms of blue printing options which help, then port miss-matching makes the best fuel standoff preventer you can get. Take for example the antipodean Alloy Head cross flow 4.1 with its 1.3" port, or the iron 250 2V with its 1.65" diameter intake port, or the iron cross flow 4.1 with its 1.38" port. Each is circular, but has a manifold which is often sharpley formed and of a lessor diameter than the intake port. Result is no loss of air flow compared to a perfectly port matched intake, but better fuel atomisation, and, if one of the common Aussie sedan racer or speedway triple Weber installations is used, you can gain significant mid range torque with no loss of high end power. If the manifold has a 60 thou annular size reduction on intake port, and even better, a 30 degree chamfer, reversion is reduced significantly.
Secondly, you then go to what I think is the Amal information used in port volume and distance to intake. Vincent motor cylcles enginering technicain Phil Irving had that stuff worked out brilliantly. Repco 2.5 Formal 1 engine optimized those settings. Apparently, according to the Chamerlain brothers account back in 1979, engines suddenly come alive when the reflecting waves are controlled by maintaining intake volumes (Vi) and intake to carb entry distance (Ced) to certain limits. A lot like the famed paint the pipe with acrylic, and saw the exhast off where the paint stops burning maxims from motorbike tuners. I assume fuel standoff is a definable quotient when the 1st, 2nd,3rd and nth degree order resonances are worked out, and that fuel standoff is actually just a function of air pressure bank-up. So Vi and Ced create an ideal tune.
Phil Irving and others define a flow net geometry cross section, where the number of flow drops to flow paths should form a lattice of squares with orthoganal (90 degree) lines, and from that, pressure gradient is made more even. Basically, the cross sectional area (Xa) can only vary a certain amount from venturi to the intake vlave to educe standing wave propigations.
One other thing. Seams like downdraft installations make a better power curve if they a packaged within the confies of variables Vi and Ced and Xa and IR peak power rpm
Independent runner venturi to peak power rpm optimisation is 99% of getting great power and wide based torque. The rest is mearly detail which could be undone by a simple air cleaner or missplaced silencer or resonator box. Similiar to how an effective optimised exhast could be totally undone by one deviation from the as dynoed ideal.
For me, the variables Vi and Ced and Xa define the nature of the intakes abilty to optimise or limit fuel standoff after a basic combination has been ratifed. See below.
Primarily, before discussing those three basic geometric design parameters above, your always stuck with a basic form to test, and then optimise, for in engine development, you always use horse trade from the existing base to the evolutionary optimum. In terms of blue printing options which help, then port miss-matching makes the best fuel standoff preventer you can get. Take for example the antipodean Alloy Head cross flow 4.1 with its 1.3" port, or the iron 250 2V with its 1.65" diameter intake port, or the iron cross flow 4.1 with its 1.38" port. Each is circular, but has a manifold which is often sharpley formed and of a lessor diameter than the intake port. Result is no loss of air flow compared to a perfectly port matched intake, but better fuel atomisation, and, if one of the common Aussie sedan racer or speedway triple Weber installations is used, you can gain significant mid range torque with no loss of high end power. If the manifold has a 60 thou annular size reduction on intake port, and even better, a 30 degree chamfer, reversion is reduced significantly.
Secondly, you then go to what I think is the Amal information used in port volume and distance to intake. Vincent motor cylcles enginering technicain Phil Irving had that stuff worked out brilliantly. Repco 2.5 Formal 1 engine optimized those settings. Apparently, according to the Chamerlain brothers account back in 1979, engines suddenly come alive when the reflecting waves are controlled by maintaining intake volumes (Vi) and intake to carb entry distance (Ced) to certain limits. A lot like the famed paint the pipe with acrylic, and saw the exhast off where the paint stops burning maxims from motorbike tuners. I assume fuel standoff is a definable quotient when the 1st, 2nd,3rd and nth degree order resonances are worked out, and that fuel standoff is actually just a function of air pressure bank-up. So Vi and Ced create an ideal tune.
Phil Irving and others define a flow net geometry cross section, where the number of flow drops to flow paths should form a lattice of squares with orthoganal (90 degree) lines, and from that, pressure gradient is made more even. Basically, the cross sectional area (Xa) can only vary a certain amount from venturi to the intake vlave to educe standing wave propigations.
One other thing. Seams like downdraft installations make a better power curve if they a packaged within the confies of variables Vi and Ced and Xa and IR peak power rpm