I recently puchased a 68 Camaro 350 Th350. It has stock intake, Edelbrock 4
barrel carb which looks to be brand new.
Car was driven in Nevada thin air, but I live at low elevation so I think it
needs a carb adjustment.
It's been a lot of years since I tried to adjust a carb, can anyone give me
It has 2 adjusting screws facing front of engine-- how do I know if it is
running too rich or too lean?
Car idles fine but accelarates unevenly, plugs are new & all firing. Any
input is appreciated-- Thanks, Terry
The screws you descibe are for idle adjustment, they will have no effect at
higher RPM. You need to change main jets and/or metering rods. Metering rods
may do it, and they are accessable from small covers in the top of the carb.
Greg, ok, I think I remember doing that a long time ago, my only experience
is the old Rochester Quadrajets. But how do I know if it's running too rich
or too lean? Should I
try various settings, trial and error, or just take it to a mechcanic to
have it fine tuned?
I'd rather work on this car myself than pay a garage-- thanks for your help,
I just took the Camaro out for a drive on the highway, it misses pretty bad
over 55 mph,
maybe it is running too lean. I'll have to check the timing too. I just
purchased this car a couple
weeks ago, so I haven't done much besides put in a new set of spark plugs.
-- Terry M.
OK, I pulled a spark plug, it has very light grey coating. Looks pretty
normal to me,
definitely not too rich. There's a little engine oil on the spark plug
threads too, but none
on the exterior of the head-- is it a sign of trouble? I'm no engine
mechanic so I'm not
sure how to interpret this. Thanks guys for your help, Terry
Plugs look ok, plug wires look new, dist. cap looks new. Here's what
car idles ok, a little miss. When I drive and accelerate slowly, car misses
with medium acceleration it's worse, sounds like it might die but doesn't.
If I floor it and open
up the 4 barrels, car accelerates fine, really takes off....anyone know what
might be causing this?
Since the carb is brand new, I'm not sure what step to do next.
Greg, I think this carb might be running lean just like you said. I took
in to a speed shop that specializes in Chevys (Corvettes) and that was the
first possibility that
they mentioned. The car was driven in Nevada so re-jetting the carb might do
the trick--- Terry
Sounds like a possible accelerator pump problem to me. Take the air clean
off and with the engine not running and cool, operate the carb a few times
to wide open position and loof for a steady stream of gas flow.
Here's a link to the manual for the Edelbrock Performer carb:
If you are going to tune the carb, you might have to buy a calibration kit
to richen the primary circuit. The calibration kit comes with jets, metering
rods and metering rod springs of various sizes.
Are you sure you don't have a vacuum leak?
Check the near the lower center front area for the carb number. It should be
something like 1405, 1406 & etc.
Then go to Edelbrock's web page and download the manual for the performer
series carbs. There is extensive tuning info in the manual.
Look up the stock components for rods, springs and jets. Buy a complete set
for your carb.
Then remove your carb and install all new stock components.
Tim, good advice I'll do just that. This morning I was considering buying a
type carb instead, because I know they are dependable and smooth running,
but it seems
like a waste of money because this Edel. carb is nearly new.
Thanks again for the help-- Terry M.
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