> > A lot to chew on for you guys, please!>
> > Car is 1970 TR6.>
> > Engine boggs under acceleration at about 3000 rpm, there is
> big change in
> > exhaust sound>
Bob, can you elaborate a bit more on what "boggs" means ? Does it only lose
some power then eventually pull to redline or will it simply not accelerate
past 3000 rpm ? If the latter, does it just hang at 3000 rpm or falter and
drop off from there ?
The first case is generally a mixture problem, commonly called a "flat
spot". Second case is generally an ignition problem or possibly air flow
(clogged air filter). Third case usually indicates fuel delivery problems.
None of these are hard and fast rules, just general guidelines on where to
start looking.
> > Engine starts excellent, even after sitting 1 week, no
> choke really needed
That is suspicious in itself. Must be running very rich if it starts easily
from cold with no choke.
> > Carb PVC ports are plugged, valve cover hose goes to
> charcoal canister
I'm not sure of the original configuration of a 70 TR6 offhand, but you
might have the wrong carbs anyway. If there are ports for the bowl vents
(as my 71 Stag has), then they should not be plugged but either open to the
air or the carbon canister. Also check that the vents through the face of
the carbs are not dirty or blocked (eg by the wrong gasket to the air
filter).
> > *****Distributor has only 1 vacuum line on firewall side
> and looks like
> front one was
> > removed?>
Later TR6 only had one vacuum line, which was for vacuum retard. I would
suggest verifying first whether the carb port is for advance or retard (a
retard port will have vacuum at idle, an advance port will not); and then
whether the unit on the dizzy is configured for advance or retard.
(Applying vacuum to a retard capsule will lower idle rpm, applying to
advance capsule will increase idle rpm.)
Getting the advance/retard mixed up can cause strange drivability problems
... if in doubt, just disconnect and cap while you solve the other problems.
Many of the books are wrong about how to set timing ... if you have the line
disconnected, the initial timing should be set to the 'static' value given
in the book, which is around 10 or 12 degrees before TDC.
The 4 ATDC figure only applies when the retard capsule is connected and
operating.
Randall
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