'79 304 Edelbrock carb problems vs Holley carbs?

The rule of thumb was during the muscle car era, was any carburetor
that came form the factory needed to be jetted by about ten percent, of
course that was too rich for the street and fouled plugs, but it was
that little edge I had on everyone.
God Bless America, Bill O|||||||O
http://www.billhughes.com/

c wrote:
>
> 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, you shouldn't have a problem tuning the Carter/Edelbrock carb, and
yes, they are basically the same carb inside. I believe the jets and rods
interchange, but I'm not positive on that. I do know that the Edelbrock carb
is heavily based on the Carter design. If you understand basic carb
functioning, and what the rods and jets do for the mixture, it will be a
simple process to get it dialed in. If you ruin in to problems, I'm sure we
can get you going in the right direction. Also, there is a book available
called Carter Carb Tuning. Most of it will apply to the Edelbrock as well. I
had the book at one time, but loaned it out and never got it back. I do know
that the book is very thorough.

Chris


"Dave Milne" > wrote in message
. uk...
> Thanks. Looks like perhaps I should have ordered the calibration kit in
> retrospect. Anyhow, after a 2 week wait, it has arrived so I'll fit at the
> weekend.
>
> Quite looking forward to it - my carb experience has been mainly with
> multiple SU's (single barrel downdraft) and the odd side draft Weber -
> never done anything on a 4 barrel like Holley or Edelbrock before.
>
> Dave Milne, Scotland
> '91 Grand Wagoneer, '99 TJ
> "c" > wrote in message
> ...
>> 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.
>> >
>> >
>> >
>>
>>
>
>

This one?

Super Tuning and Modifying Carter Carburetors for Performance,
Street and Off-Road Applications, Dave Emanuel

http://www.amazon.com/o/ASIN/0931472113/


"c" > wrote in message
...
> Dave, you shouldn't have a problem tuning the Carter/Edelbrock
> carb, and yes, they are basically the same carb inside. I
> believe the jets and rods interchange, but I'm not positive on
> that. I do know that the Edelbrock carb is heavily based on the
> Carter design. If you understand basic carb functioning, and
> what the rods and jets do for the mixture, it will be a simple
> process to get it dialed in. If you ruin in to problems, I'm
> sure we can get you going in the right direction. Also, there
> is a book available called Carter Carb Tuning. Most of it will
> apply to the Edelbrock as well. I had the book at one time, but
> loaned it out and never got it back. I do know that the book is
> very thorough.
>
> Chris
>
>
> "Dave Milne" > wrote in message
> . uk...
>> Thanks. Looks like perhaps I should have ordered the
>> calibration kit in
>> retrospect. Anyhow, after a 2 week wait, it has arrived so
>> I'll fit at the
>> weekend.
>>
>> Quite looking forward to it - my carb experience has been
>> mainly with
>> multiple SU's (single barrel downdraft) and the odd side
>> draft Weber -
>> never done anything on a 4 barrel like Holley or Edelbrock
>> before.
>>
>> Dave Milne, Scotland
>> '91 Grand Wagoneer, '99 TJ
>> "c" > wrote in message
>> ...
>>> 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.
>>> >
>>> >
>>> >
>>>
>>>
>>
>>
>
>

AFB: http://www.carburetorfactory.com/expvw04.html
God Bless America, Bill O|||||||O
http://www.billhughes.com/

c wrote:
>
> Dave, you shouldn't have a problem tuning the Carter/Edelbrock carb, and
> yes, they are basically the same carb inside. I believe the jets and rods
> interchange, but I'm not positive on that. I do know that the Edelbrock carb
> is heavily based on the Carter design. If you understand basic carb
> functioning, and what the rods and jets do for the mixture, it will be a
> simple process to get it dialed in. If you ruin in to problems, I'm sure we
> can get you going in the right direction. Also, there is a book available
> called Carter Carb Tuning. Most of it will apply to the Edelbrock as well. I
> had the book at one time, but loaned it out and never got it back. I do know
> that the book is very thorough.
>
> Chris

Yup, that's the one.

Chris

"Frank" > wrote in message
newscQLg.10407$YZ3.927@trnddc03...
> This one?
>
> Super Tuning and Modifying Carter Carburetors for Performance, Street and
> Off-Road Applications, Dave Emanuel
>
> http://www.amazon.com/o/ASIN/0931472113/
>
>
> "c" > wrote in message
> ...
>> Dave, you shouldn't have a problem tuning the Carter/Edelbrock carb, and
>> yes, they are basically the same carb inside. I believe the jets and rods
>> interchange, but I'm not positive on that. I do know that the Edelbrock
>> carb is heavily based on the Carter design. If you understand basic carb
>> functioning, and what the rods and jets do for the mixture, it will be a
>> simple process to get it dialed in. If you ruin in to problems, I'm sure
>> we can get you going in the right direction. Also, there is a book
>> available called Carter Carb Tuning. Most of it will apply to the
>> Edelbrock as well. I had the book at one time, but loaned it out and
>> never got it back. I do know that the book is very thorough.
>>
>> Chris
>>
>>
>> "Dave Milne" > wrote in message
>> . uk...
>>> Thanks. Looks like perhaps I should have ordered the calibration kit in
>>> retrospect. Anyhow, after a 2 week wait, it has arrived so I'll fit at
>>> the
>>> weekend.
>>>
>>> Quite looking forward to it - my carb experience has been mainly with
>>> multiple SU's (single barrel downdraft) and the odd side draft Weber -
>>> never done anything on a 4 barrel like Holley or Edelbrock before.
>>>
>>> Dave Milne, Scotland
>>> '91 Grand Wagoneer, '99 TJ
>>> "c" > wrote in message
>>> ...
>>>> 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.
>>>> >
>>>> >
>>>> >
>>>>
>>>>
>>>
>>>
>>
>>
>
>

Our rule of thumb was to leave the carbs alone and fix the ignition
system first. Then open up the exhaust with good headers and pipes at
which point you could usually go a bit richer on the carbs without
fouling plugs as much at low speed. Best to put on a good manifold as
well. With a really good ignition, the plug fouling was usually not as
big a problem, often with a bypass to go back to stock to make it easier
to read the plugs for tuning the gas/air flow.




L.W.(Bill) Hughes III proclaimed:

> The rule of thumb was during the muscle car era, was any carburetor
> that came form the factory needed to be jetted by about ten percent, of
> course that was too rich for the street and fouled plugs, but it was
> that little edge I had on everyone.
> God Bless America, Bill O|||||||O
> http://www.billhughes.com/
>
> c wrote:
>
>>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

Mallory dual point, total 38 degrees on the crank. first transistor
ignitions were junk along with all factory stock ignition that limited
at five grand.
God Bless America, Bill O|||||||O
http://www.billhughes.com/

Lon wrote:
>
> Our rule of thumb was to leave the carbs alone and fix the ignition
> system first. Then open up the exhaust with good headers and pipes at
> which point you could usually go a bit richer on the carbs without
> fouling plugs as much at low speed. Best to put on a good manifold as
> well. With a really good ignition, the plug fouling was usually not as
> big a problem, often with a bypass to go back to stock to make it easier
> to read the plugs for tuning the gas/air flow.

Chrysler's first generation electronic ignition was accurate to 9000+ rpm.

They came both with and without limiters. The models with limiters came in
2 or 3 settings

There was also an easy to install retrofit available from the parts
department that was initially limited to the V-8 models.

"L.W.(Bill) Hughes III" > wrote in message
...
> Mallory dual point, total 38 degrees on the crank. first transistor
> ignitions were junk along with all factory stock ignition that limited
> at five grand.
> God Bless America, Bill O|||||||O
> http://www.billhughes.com/
>
> Lon wrote:
>>
>> Our rule of thumb was to leave the carbs alone and fix the ignition
>> system first. Then open up the exhaust with good headers and pipes at
>> which point you could usually go a bit richer on the carbs without
>> fouling plugs as much at low speed. Best to put on a good manifold as
>> well. With a really good ignition, the plug fouling was usually not as
>> big a problem, often with a bypass to go back to stock to make it easier
>> to read the plugs for tuning the gas/air flow.

Best ignition ever made used radar pulse transformers with local
oscillators and a pickup wheel rather than points. Generated a pretty
good burst of high voltage pulses that were width modulated by the
pickup wheel. No point bounce, superheavy spark at low rpm, the voltage
could be bumped at high rpm. Not too many sold commercially by the guy
that invented it, but you could build your own if you were a radar tech.
A bit noisy in the RF range since you were generating a pulse train
rather than a single spark, and rather pricey unless you had access to
something like a T-9 Radar. Then Delta and a few other folks made
electronic ignitions that didn't suck as badly...

Dual points worked, dual plugs worked even better but dunno anyone using
them since the old straight 8 Nash engines of the late 30's.

L.W.(Bill) Hughes III proclaimed:

> Mallory dual point, total 38 degrees on the crank. first transistor
> ignitions were junk along with all factory stock ignition that limited
> at five grand.
> God Bless America, Bill O|||||||O
> http://www.billhughes.com/
>
> Lon wrote:
>
>>Our rule of thumb was to leave the carbs alone and fix the ignition
>>system first. Then open up the exhaust with good headers and pipes at
>>which point you could usually go a bit richer on the carbs without
>>fouling plugs as much at low speed. Best to put on a good manifold as
>>well. With a really good ignition, the plug fouling was usually not as
>>big a problem, often with a bypass to go back to stock to make it easier
>>to read the plugs for tuning the gas/air flow.

Alfa Romeo have been using "twin spark" engines as they call them, since the
60's (and still use them today).
I had the 3.0 v6 hemi which was conventional - they only did them on the 4
cylinder models which ran up to 2 litres.

Dave Milne, Scotland

"Lon" > wrote in message
. ..

> Dual points worked, dual plugs worked even better but dunno anyone using
> them since the old straight 8 Nash engines of the late 30's.