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5000+ RPM Miss

In trying to find the source of a 5000+ rpm miss:
> I just talked with them and they seem fairly certain that my
> problems are fuel delivery.  Since I've eliminated the carb
> they're recommending I move to an aftermarket hi=ADperf fuel pump.

I don't know, Gordon - either I'm misunderstanding something about your RPM
problem, or everyone else just bought stock in fuel delivery systems!

You can HOLD it at 5000, it feels like a rev limiter, right? It doesn't hit
5000 and fall down to 2000 if you stay on the pedal, right? THAT would mean
fuel delivery problems. If you ever had vapor-lock, you know what I mean.

As far as the "throttle plates opening too far" is concerned, they would
have to be WAY off to limit you to 5000. I can go 5000 with Q-jet
primaries. It accelerates slowly, but it doesn't hit a sudden cut-off RPM.
What you described doesn't sound like a smooth leveling-off at 5000; it
hits 5000 fairly quickly and just won't climb, right?

Do all the FREE things first:

1. Take your engine up to 4500 RPM with as little throttle as possible,
then mash the pedal. Your fuel bowls will be full since you had minimal
load until you floored it. If it doesn't shoot right up to 6000, fuel
delivery has nothing to do with it. (If it DOES, try it in higher gears -
it should happen at lower RPM in higher gears if there is a fuel problem)

2. Try retarding timing. Also check the mechanical advance limiting
bushing. If it's gone, you get over-advance at high RPMS (only affects you
at full-throttle)

3. Try closing the plug gap a little. 

4. Try bypassing you ignition amplifier box.

5. THEN think about spending money on guesses. (and my first one would be
spark plugs)

                                    - Kerry (I'm still willing to put money
on this)

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