Re: LT5 Info.., and 1228331 stuff in general.

[Marc Randolph <mrand@pobox.com>]

On Wed, Jan 19, 2000 at 11:11:32AM -0500, Ken Kelly wrote:
> Marc,
> 	Let me barge into this thread and see if I understand what
> is going on! I don't know if we all understand how the LT5
> works. Here is my AssUMption. It is from logic only, I have
> not worked on an LT5. I assume there is only one throttle
> body, The secondary throttle that are all open or all closed
> are after the one throttle body. This would make sense in
> your argument. If this is not true, then I have a problem
> with this discussion. If both injectors have the same pulse
> width, then both runners must have a similar airflow. If one
> set of runners have an On off throttle plate to the
> atmosphere, this would not be true. If the On-off throttle
> is internal, and therefore sees the same manifold vacuum as
> the other runners, all should work well.


Howdy Ken,

Yes, you're correct - the port throttles are 8 individual 
throttle blades that are located in the heads, well 
after the fuel injectors, the runners, the [one] manifold,
and the throttle body [working up].  Supposedly development
engineers experimented with a multiplane manifold but 
did not see much benefit.

The secondary runners (which are non-functional when the port 
throttles are closed) have a slightly larger diameter than
the primaries, but are otherwise the same thing (following
the same runner path) and see the same manifold vacuum.

Have fun,

   Marc

-- 
  Marc Randolph     -    mrand@pobox.com    -     PGP keyID: 0x4C95994D
     If you have any info on the mid-60's car called the Bill Thomas
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