Atomisation Re: Intake manifold construction, intercoolers

[Dave Williams]

-> So what you are saying is that carbs (I guess not all) have better
-> atomisation than port injection? and consequently lower BSFC? (As a
-> generalised statement - feel free to go into much detail).

 Running throttled, steady state - yes.  A TBI system can match a
carburetor under those conditions, but a port injection setup can't.
Conventional Bendix-type injectors do a poor job of atomization, and too
much of their output is in gobbets too big to be fully consumed during
the power stroke, and the unburned portion goes out the exhaust valve.
This is not normally an issue for EFI cars since most of them use
catalytic convertors and the fuel is burned in the convertor, keeping it
hot enough to function when exhaust flow is low.

 Just because it's new and complicated doesn't mean EFI is better under
every condition.  Eventually rail pressures will get high enough to do a
better job of atomization, but right now all injectors are pretty much
the same.

 Part-throttle cruise is where carbs and TBIs rule, but that doesn't
play much of a part in EPA smog or mileage testing.  They assume
everyone lives in an anthill of traffic.  However, for some of us, part
throttle cruise is the dominant driving mode.

==dave.williams at chaos.lrk.ar.us======================================
I've got a secret / I've been hiding / under my skin / | Who are you?
my heart is human / my blood is boiling / my brain IBM |   who, who?
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