Dave,

When the companies that make carb give them their initial settings from the
factory, they take all kinds of compromised in to consideration. They don't
know if the carb will be used on a large or small displacement engine, or if
it will be used in hot or cold climate, high altitude, etc. They also don't
know what other mods have been done to these engines. The baseline settings
they give these carbs will allow them to run on most of the applications
they will see, but they almost always require tuning to get them to be
optimal. My guess would be that this carb would still be a little rich, but
it is just a guess. I'm not saying it won't run, it will, and it will
probably be pretty damn close to right.

The metering rod system that Carter/Edelbrock uses will "adjust" the mixture
based on engine vacuum. The rods are controlled by a piston and spring,
similar to many other carbs. When the engine vacuum is low, the metering rod
spring will start to overtake the vacuum pulling the piston down. The rods
are tapered, and when they move up in the bore they are in, a smaller
diameter of the rod will still be inside the main jet, effectively
increasing the total main jet area that fuel can pass thru. If the engine
runs too rich at high vacuum conditions, but is ok at low vacuum or wide
open throttle, then you simply change the metering rod to on the has a
larger diameter on the part of the rod that is in the jet at high vacuum
conditions. It really is a simple process, and normally will only require 1
or 2 sets of rods to get the carb where you need it to be.

Chris


"Dave Milne" > wrote in message
. uk...
> Any idea if the Edelbrock 600cfm 1405 Performer + Edelbrock 2131 manifold
> will require a metering or jet change on a stock 360 '91 Grand Wagoneer ?
>
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
> "c" > wrote in message
> ...
>> Without knowing what size carb, choke or no choke, and which manifold, it
> is
>> hard to tell you what the problem could be. What I can tell you is that
>> Edelbrock and Holley carbs are both set up from the factory with a
>> general
>> tune. This mean the carb may or may not need to be set up properly for
> your
>> particular engine. In general, the Edelbrock carbs run too rich with the
>> factory set up. Normally they will require a metering rod change, and
> maybe
>> a jet change as well. You also don't specify the cam specs.
>
>
>