. The symptom is an annoying
> 'surge' or 'buck' at lower RPM in steady state cruise, most noticeable at
> about 3000 RPM but present at 2000 RPM. This is distinct from the lumpy
idle
> that the cam produces, it just seems to erratically fluctuate making it
hard
> to hold a steady speed. Full acceleration is crisp, and in fact startling
at
> 3000+ RPM.
>
>
> Can anyone think of something that will cause my engine to accelerate well
yet
> not hold a steady RPM well. I would expect a over rich or lean carb to be
> somewhat consistant, and a faulty ignition to get worse at high RPM or
WOT.
> Once off of idle the vacuum is quite steady and it is not too bad even at
> idle, so I doubt a vacuum leak is the answer either.
>
> Help! I am tired of paying for mechanics to make the same guesses that I
made
> six months ago, but I still think that even a high performance engine
should
> be able to hold a steady RPM once it is in its powerband.
>
> Thank you in advance for your input
>
> Michael McBeth
I would looking for a lean condition. It could be a vacuum leak that is
masked by the jetting at higher speeds.
It could also be a jetting/mixture problem. Are these carbs out of the box?
With that cam the Idle and low speed circuit will need to be recalibrated.
Basically the engine doesn't have enough vacuum to pull fuel through the
bleeds. They may need to be enlarged. There are several good books out on
Holley carbs. If you this sounds like more than you want to take on call
"The Carb Shop" in CA. They will calibrate the carb to match your engine
combination. The last time I did this all that was required was bolting it
on and setting the idle speed. They do great work.
Good luck!!
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