A
Anonymous
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would ther be much advantage to using a standard e/au series intake manifold (on crossflow 250) and fittiting a couple of small throttle bodies (say from a laser or something similar) say three of them?
Yes....but!
A single Central (CFI) or Throttle body injection (TBI) has a worse fuel vapourisation control than even a stock 1 or 2-bbl carb. It's lousy, and it works well only when split up for multi throttle body set-ups which can pulse tune the mixture into each port without contacting port walls. Even though the stock EA set-up isn't bad as manifolds go, it will produce an inferior zone of seperation at various points in the fuel delivery. One word from The Frenchtown Flyer was enough...the roosters tail of fuel vaporisation is 'lousy'
Any time you reduce the time of travel, and reduce the wetted perimeter of port, you all ways get better response, power and specific fuel ecconomy. Always, except where, becasue of bad porting or design, the intake mixture draw-in is unstable, like in 9 port Holdens or 2 port BMC A-series engines.
How far you have to go to do this oftenmakes it impractical to mak any further 'killer' triple TBI set-ups. Running three cut-up John Cain 2-bbl, EA or XE intakes with three ADM or EA CFI throttle bodies would be okay if you can get the software and wet gear set-up to suit. Few do.
I wouldn't bother as the modifying two stock XE intakes will give much better chances of making a CFI system work well. You double the chances of the fuel flowing with no space issues on any of the bodies the cross-flow is found in.
A single Central (CFI) or Throttle body injection (TBI) has a worse fuel vapourisation control than even a stock 1 or 2-bbl carb. It's lousy, and it works well only when split up for multi throttle body set-ups which can pulse tune the mixture into each port without contacting port walls. Even though the stock EA set-up isn't bad as manifolds go, it will produce an inferior zone of seperation at various points in the fuel delivery. One word from The Frenchtown Flyer was enough...the roosters tail of fuel vaporisation is 'lousy'
Any time you reduce the time of travel, and reduce the wetted perimeter of port, you all ways get better response, power and specific fuel ecconomy. Always, except where, becasue of bad porting or design, the intake mixture draw-in is unstable, like in 9 port Holdens or 2 port BMC A-series engines.
How far you have to go to do this oftenmakes it impractical to mak any further 'killer' triple TBI set-ups. Running three cut-up John Cain 2-bbl, EA or XE intakes with three ADM or EA CFI throttle bodies would be okay if you can get the software and wet gear set-up to suit. Few do.
I wouldn't bother as the modifying two stock XE intakes will give much better chances of making a CFI system work well. You double the chances of the fuel flowing with no space issues on any of the bodies the cross-flow is found in.
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