Fuel Injection

[Brian Knowles]

John Dammeyer asked:
>
>Would someone lay out the advantages/disadvantages of the following:
>
>Throttle Body Injection:
Advantages:  All to the  manufacturer.  Cheap to make, uses same ol' 
manifold.
Disavantages:  One barrel carburetor.  Uses same ol' manifold.  May have 
mandated  non-performance enhancing electronics.
>
>Constant Flow, Multi-Port Injection
Advantages:  Works just like Weber carbs, may need no electronics, none 
of carb or TBI air/fuel manifold  problems.
Disavantages:  Hard to get for large displacement engines.  Expensive.  
Tuning mysterious and difficult.  Some later systems have electronics, 
not for performance but for smog nazis.
>
>Sequential Multi-Port Injection.
Advantages:  Wide availability, junkyards full of 'em. Parts common and 
relitvly cheap.
Disavantages:  Most are smog control stuff that incidently lets the 
engine run.  Every manufacturer different.  Unknown code and secret 
parts, documentation marginal, source code propriatery.  Good luck trying 
to sort out actual engine managment from manufactures agenda, fed govt 
agenda.

>Obviously each is more complicated and more expensive so that would be a
>down side but why go for something as complex as Sequential Multi-port when
>Constant flow would also work.

Yeah, thats the right question. 
 I really can't think of a reason to use EFI if mechanical injection is 
available.

Brian