Steve,
Had a similar problem. The internal stop on the vascuum advance had
broken which allowed too much advance ( due to high vacuum) at a
constant speed. When accelerating, the vacuum drops and the timing
was retarded enough to run good. In my case I would actually backfire
sometimes ( which would drop the vacuum) and then the Tiger ran OK for
a second or two until the vacuum was high again. However you state that you
have mechanical advance, so that leaves a vacuum leak at the intake.
When you accelerate, you add additional fuel from accelerator pump
and from the powervalve which can cover up the air leak problem.
The smooth idle may be due to the carb idle being set too rich
for non-leaking operation.
At 08:36 PM 2/20/2001 -0800, you wrote:
>Hello Sunbeamers:
>I took the Tiger out for a good run today (in between the rain) and
>notice that while it accelerates really fast when under full load, at
>any cruising speed, whether its at 35 MPH or 65 MPH (or any speed), the
>car seems to almost have a bit of a "sputter". Not too bad, but it just
>starts to hesitate when the speed is held steady (at any speed). More
>pressure on the pedal and into acceleration mode and this goes away
>until I reach cruising speed again. Could this have anything to do with
>a vacuum leak, points gap (I have a Ford mechanical advance dual point
>distributor), etc.?
>
>I noticed when I installed my new Holley carb a few days ago that the
>guys who had installed my "new" used engine had not done a proper job on
>tightening the manifold. The passenger side bolts were barely snugged
>down and the back bolt (under the firewall) was turnable by hand, it was
>so loose. I gently snugged bown the bolts but I wonder if there could be
>a problem here. The car does idle pretty smoothly, though.
>
>Steve Sage
>1967 MK1A 289
>
James Barrett Tiger II 351C and others
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