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Drink 02-22-2004 09:23 PM

No Measurable Vacuum at Idle???
 
Here's something I've pondered for years...
When I tune the Jeep, I have no measurable vacuum at idle. If I raise the
RPM above idle around 1,000 and up (revving high), it shows plenty of
vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter YF
carb with minimal emissions. In fact, the only thing I have is the vacuum
advance ported from the carb, PCV to manifold, canister to manifold and
canister pulling vapor from around the bowl. The intake manifold ports were
all plugged with bungs. I'm describing the plumbing from memory. So, don't
quote me but I'm pretty sure that's it. The engine runs just fine besides
being cold natured. but, it ain't a problem down here in Florida.
All the hoses are in fine shape and I can't find any leaks anywhere. I've
torqued the manifolds and they've never leaked either through various head
and manifold swaps. The carb's tight too. So, what's the deal with an
otherwise healthy engine that shows good compression. The distributor's new
and I've ruled out a ruptured diaphragm. What could it be? Am I being
stupid and there shouldn't be any measured vacuum at idle?
o_o_o_o
Best Regards, /| ,[_____],
Jim, WP3JQ |¯¯¯L --O|||||||O-
()_)¯()_) ¯¯¯¯¯ )_)
EM60qk 30.447439N 086.628959W



L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III 02-22-2004 10:10 PM

Re: No Measurable Vacuum at Idle???
 
That's normal and is the venturi vacuum port, the stock and what
Mike here likes to hook the distributor diaphragm to, that advances the
timing as the engine increases in revolutions per minute. You find full
manifold vacuum down at the butterfly throttle plates about fifteen
inches of mercury at idle. This port I favor for full advance at idle
(makes for smooth idle) yet instantly retards for torque when you stick
it, and gradually advances with the centrifugal weights to reach full
advance together somewhere between two and three grand.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Drink wrote:
>
> Here's something I've pondered for years...
> When I tune the Jeep, I have no measurable vacuum at idle. If I raise the
> RPM above idle around 1,000 and up (revving high), it shows plenty of
> vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter YF
> carb with minimal emissions. In fact, the only thing I have is the vacuum
> advance ported from the carb, PCV to manifold, canister to manifold and
> canister pulling vapor from around the bowl. The intake manifold ports were
> all plugged with bungs. I'm describing the plumbing from memory. So, don't
> quote me but I'm pretty sure that's it. The engine runs just fine besides
> being cold natured. but, it ain't a problem down here in Florida.
> All the hoses are in fine shape and I can't find any leaks anywhere. I've
> torqued the manifolds and they've never leaked either through various head
> and manifold swaps. The carb's tight too. So, what's the deal with an
> otherwise healthy engine that shows good compression. The distributor's new
> and I've ruled out a ruptured diaphragm. What could it be? Am I being
> stupid and there shouldn't be any measured vacuum at idle?
> o_o_o_o
> Best Regards, /| ,[_____],
> Jim, WP3JQ |¯¯¯L --O|||||||O-
> ()_)¯()_) ¯¯¯¯¯ )_)
> EM60qk 30.447439N 086.628959W


L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III 02-22-2004 10:10 PM

Re: No Measurable Vacuum at Idle???
 
That's normal and is the venturi vacuum port, the stock and what
Mike here likes to hook the distributor diaphragm to, that advances the
timing as the engine increases in revolutions per minute. You find full
manifold vacuum down at the butterfly throttle plates about fifteen
inches of mercury at idle. This port I favor for full advance at idle
(makes for smooth idle) yet instantly retards for torque when you stick
it, and gradually advances with the centrifugal weights to reach full
advance together somewhere between two and three grand.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Drink wrote:
>
> Here's something I've pondered for years...
> When I tune the Jeep, I have no measurable vacuum at idle. If I raise the
> RPM above idle around 1,000 and up (revving high), it shows plenty of
> vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter YF
> carb with minimal emissions. In fact, the only thing I have is the vacuum
> advance ported from the carb, PCV to manifold, canister to manifold and
> canister pulling vapor from around the bowl. The intake manifold ports were
> all plugged with bungs. I'm describing the plumbing from memory. So, don't
> quote me but I'm pretty sure that's it. The engine runs just fine besides
> being cold natured. but, it ain't a problem down here in Florida.
> All the hoses are in fine shape and I can't find any leaks anywhere. I've
> torqued the manifolds and they've never leaked either through various head
> and manifold swaps. The carb's tight too. So, what's the deal with an
> otherwise healthy engine that shows good compression. The distributor's new
> and I've ruled out a ruptured diaphragm. What could it be? Am I being
> stupid and there shouldn't be any measured vacuum at idle?
> o_o_o_o
> Best Regards, /| ,[_____],
> Jim, WP3JQ |¯¯¯L --O|||||||O-
> ()_)¯()_) ¯¯¯¯¯ )_)
> EM60qk 30.447439N 086.628959W


L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III 02-22-2004 10:10 PM

Re: No Measurable Vacuum at Idle???
 
That's normal and is the venturi vacuum port, the stock and what
Mike here likes to hook the distributor diaphragm to, that advances the
timing as the engine increases in revolutions per minute. You find full
manifold vacuum down at the butterfly throttle plates about fifteen
inches of mercury at idle. This port I favor for full advance at idle
(makes for smooth idle) yet instantly retards for torque when you stick
it, and gradually advances with the centrifugal weights to reach full
advance together somewhere between two and three grand.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Drink wrote:
>
> Here's something I've pondered for years...
> When I tune the Jeep, I have no measurable vacuum at idle. If I raise the
> RPM above idle around 1,000 and up (revving high), it shows plenty of
> vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter YF
> carb with minimal emissions. In fact, the only thing I have is the vacuum
> advance ported from the carb, PCV to manifold, canister to manifold and
> canister pulling vapor from around the bowl. The intake manifold ports were
> all plugged with bungs. I'm describing the plumbing from memory. So, don't
> quote me but I'm pretty sure that's it. The engine runs just fine besides
> being cold natured. but, it ain't a problem down here in Florida.
> All the hoses are in fine shape and I can't find any leaks anywhere. I've
> torqued the manifolds and they've never leaked either through various head
> and manifold swaps. The carb's tight too. So, what's the deal with an
> otherwise healthy engine that shows good compression. The distributor's new
> and I've ruled out a ruptured diaphragm. What could it be? Am I being
> stupid and there shouldn't be any measured vacuum at idle?
> o_o_o_o
> Best Regards, /| ,[_____],
> Jim, WP3JQ |¯¯¯L --O|||||||O-
> ()_)¯()_) ¯¯¯¯¯ )_)
> EM60qk 30.447439N 086.628959W


Drink 02-22-2004 10:49 PM

Re: No Measurable Vacuum at Idle???
 
You lost me, I think, about where to connect vacuum advance. From the
passenger side, there are two vacuum ports. At the base, where I'm
connecting distributor vacuum, is all the way down on the right. About 3/4
inch higher, to the left is the other. I checked vacuum at both and neither
presents measurable vacuum but the lower (my connection) provides more
vacuum at RPM. So, where do you connect?
What benefit do you get by connecting your way? It seems backwards until
much higher RPM since you have vacuum advance at idle and then no advance
upon acceleration. At rev, it sounds like vacuum catches up and you're back
to where you want to be.
o_o_o_o
Best Regards, /| ,[_____],
Jim, WP3JQ |¯¯¯L --O|||||||O-
()_)¯()_) ¯¯¯¯¯ )_)
EM60qk 30.447439N 086.628959W
"L.W. (ßill) ------ III" <----------@cox.net> wrote in message
news:40396F0C.E76FCBD5@cox.net...
> That's normal and is the venturi vacuum port, the stock and what
> Mike here likes to hook the distributor diaphragm to, that advances the
> timing as the engine increases in revolutions per minute. You find full
> manifold vacuum down at the butterfly throttle plates about fifteen
> inches of mercury at idle. This port I favor for full advance at idle
> (makes for smooth idle) yet instantly retards for torque when you stick
> it, and gradually advances with the centrifugal weights to reach full
> advance together somewhere between two and three grand.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Drink wrote:
> >
> > Here's something I've pondered for years...
> > When I tune the Jeep, I have no measurable vacuum at idle. If I raise

the
> > RPM above idle around 1,000 and up (revving high), it shows plenty of
> > vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter

YF
> > carb with minimal emissions. In fact, the only thing I have is the

vacuum
> > advance ported from the carb, PCV to manifold, canister to manifold and
> > canister pulling vapor from around the bowl. The intake manifold ports

were
> > all plugged with bungs. I'm describing the plumbing from memory. So,

don't
> > quote me but I'm pretty sure that's it. The engine runs just fine

besides
> > being cold natured. but, it ain't a problem down here in Florida.
> > All the hoses are in fine shape and I can't find any leaks anywhere.

I've
> > torqued the manifolds and they've never leaked either through various

head
> > and manifold swaps. The carb's tight too. So, what's the deal with an
> > otherwise healthy engine that shows good compression. The distributor's

new
> > and I've ruled out a ruptured diaphragm. What could it be? Am I being
> > stupid and there shouldn't be any measured vacuum at idle?
> > o_o_o_o
> > Best Regards, /| ,[_____],
> > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > ()_)¯()_) ¯¯¯¯¯ )_)
> > EM60qk 30.447439N 086.628959W




Drink 02-22-2004 10:49 PM

Re: No Measurable Vacuum at Idle???
 
You lost me, I think, about where to connect vacuum advance. From the
passenger side, there are two vacuum ports. At the base, where I'm
connecting distributor vacuum, is all the way down on the right. About 3/4
inch higher, to the left is the other. I checked vacuum at both and neither
presents measurable vacuum but the lower (my connection) provides more
vacuum at RPM. So, where do you connect?
What benefit do you get by connecting your way? It seems backwards until
much higher RPM since you have vacuum advance at idle and then no advance
upon acceleration. At rev, it sounds like vacuum catches up and you're back
to where you want to be.
o_o_o_o
Best Regards, /| ,[_____],
Jim, WP3JQ |¯¯¯L --O|||||||O-
()_)¯()_) ¯¯¯¯¯ )_)
EM60qk 30.447439N 086.628959W
"L.W. (ßill) ------ III" <----------@cox.net> wrote in message
news:40396F0C.E76FCBD5@cox.net...
> That's normal and is the venturi vacuum port, the stock and what
> Mike here likes to hook the distributor diaphragm to, that advances the
> timing as the engine increases in revolutions per minute. You find full
> manifold vacuum down at the butterfly throttle plates about fifteen
> inches of mercury at idle. This port I favor for full advance at idle
> (makes for smooth idle) yet instantly retards for torque when you stick
> it, and gradually advances with the centrifugal weights to reach full
> advance together somewhere between two and three grand.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Drink wrote:
> >
> > Here's something I've pondered for years...
> > When I tune the Jeep, I have no measurable vacuum at idle. If I raise

the
> > RPM above idle around 1,000 and up (revving high), it shows plenty of
> > vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter

YF
> > carb with minimal emissions. In fact, the only thing I have is the

vacuum
> > advance ported from the carb, PCV to manifold, canister to manifold and
> > canister pulling vapor from around the bowl. The intake manifold ports

were
> > all plugged with bungs. I'm describing the plumbing from memory. So,

don't
> > quote me but I'm pretty sure that's it. The engine runs just fine

besides
> > being cold natured. but, it ain't a problem down here in Florida.
> > All the hoses are in fine shape and I can't find any leaks anywhere.

I've
> > torqued the manifolds and they've never leaked either through various

head
> > and manifold swaps. The carb's tight too. So, what's the deal with an
> > otherwise healthy engine that shows good compression. The distributor's

new
> > and I've ruled out a ruptured diaphragm. What could it be? Am I being
> > stupid and there shouldn't be any measured vacuum at idle?
> > o_o_o_o
> > Best Regards, /| ,[_____],
> > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > ()_)¯()_) ¯¯¯¯¯ )_)
> > EM60qk 30.447439N 086.628959W




Drink 02-22-2004 10:49 PM

Re: No Measurable Vacuum at Idle???
 
You lost me, I think, about where to connect vacuum advance. From the
passenger side, there are two vacuum ports. At the base, where I'm
connecting distributor vacuum, is all the way down on the right. About 3/4
inch higher, to the left is the other. I checked vacuum at both and neither
presents measurable vacuum but the lower (my connection) provides more
vacuum at RPM. So, where do you connect?
What benefit do you get by connecting your way? It seems backwards until
much higher RPM since you have vacuum advance at idle and then no advance
upon acceleration. At rev, it sounds like vacuum catches up and you're back
to where you want to be.
o_o_o_o
Best Regards, /| ,[_____],
Jim, WP3JQ |¯¯¯L --O|||||||O-
()_)¯()_) ¯¯¯¯¯ )_)
EM60qk 30.447439N 086.628959W
"L.W. (ßill) ------ III" <----------@cox.net> wrote in message
news:40396F0C.E76FCBD5@cox.net...
> That's normal and is the venturi vacuum port, the stock and what
> Mike here likes to hook the distributor diaphragm to, that advances the
> timing as the engine increases in revolutions per minute. You find full
> manifold vacuum down at the butterfly throttle plates about fifteen
> inches of mercury at idle. This port I favor for full advance at idle
> (makes for smooth idle) yet instantly retards for torque when you stick
> it, and gradually advances with the centrifugal weights to reach full
> advance together somewhere between two and three grand.
> God Bless America, ßill O|||||||O
> mailto:-------------------- http://www.----------.com/
>
> Drink wrote:
> >
> > Here's something I've pondered for years...
> > When I tune the Jeep, I have no measurable vacuum at idle. If I raise

the
> > RPM above idle around 1,000 and up (revving high), it shows plenty of
> > vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter

YF
> > carb with minimal emissions. In fact, the only thing I have is the

vacuum
> > advance ported from the carb, PCV to manifold, canister to manifold and
> > canister pulling vapor from around the bowl. The intake manifold ports

were
> > all plugged with bungs. I'm describing the plumbing from memory. So,

don't
> > quote me but I'm pretty sure that's it. The engine runs just fine

besides
> > being cold natured. but, it ain't a problem down here in Florida.
> > All the hoses are in fine shape and I can't find any leaks anywhere.

I've
> > torqued the manifolds and they've never leaked either through various

head
> > and manifold swaps. The carb's tight too. So, what's the deal with an
> > otherwise healthy engine that shows good compression. The distributor's

new
> > and I've ruled out a ruptured diaphragm. What could it be? Am I being
> > stupid and there shouldn't be any measured vacuum at idle?
> > o_o_o_o
> > Best Regards, /| ,[_____],
> > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > ()_)¯()_) ¯¯¯¯¯ )_)
> > EM60qk 30.447439N 086.628959W




L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III 02-22-2004 11:10 PM

Re: No Measurable Vacuum at Idle???
 
I know I'll get an argument out of Mike Romain here, but manifold
vacuum will get you a better idle and fuel mileage. Try the port over
the number 59 in this view:
http://www.carburetorfactory.com/expvw03.html You might go around it
tightening all the screws, because it should have been easy for you to
find full vacuum, virtually all of them other than the venturi one.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Drink wrote:
>
> You lost me, I think, about where to connect vacuum advance. From the
> passenger side, there are two vacuum ports. At the base, where I'm
> connecting distributor vacuum, is all the way down on the right. About 3/4
> inch higher, to the left is the other. I checked vacuum at both and neither
> presents measurable vacuum but the lower (my connection) provides more
> vacuum at RPM. So, where do you connect?
> What benefit do you get by connecting your way? It seems backwards until
> much higher RPM since you have vacuum advance at idle and then no advance
> upon acceleration. At rev, it sounds like vacuum catches up and you're back
> to where you want to be.
> o_o_o_o
> Best Regards, /| ,[_____],
> Jim, WP3JQ |¯¯¯L --O|||||||O-
> ()_)¯()_) ¯¯¯¯¯ )_)
> EM60qk 30.447439N 086.628959W
> "L.W. (ßill) ------ III" <----------@cox.net> wrote in message
> news:40396F0C.E76FCBD5@cox.net...
> > That's normal and is the venturi vacuum port, the stock and what
> > Mike here likes to hook the distributor diaphragm to, that advances the
> > timing as the engine increases in revolutions per minute. You find full
> > manifold vacuum down at the butterfly throttle plates about fifteen
> > inches of mercury at idle. This port I favor for full advance at idle
> > (makes for smooth idle) yet instantly retards for torque when you stick
> > it, and gradually advances with the centrifugal weights to reach full
> > advance together somewhere between two and three grand.
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
> > Drink wrote:
> > >
> > > Here's something I've pondered for years...
> > > When I tune the Jeep, I have no measurable vacuum at idle. If I raise

> the
> > > RPM above idle around 1,000 and up (revving high), it shows plenty of
> > > vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter

> YF
> > > carb with minimal emissions. In fact, the only thing I have is the

> vacuum
> > > advance ported from the carb, PCV to manifold, canister to manifold and
> > > canister pulling vapor from around the bowl. The intake manifold ports

> were
> > > all plugged with bungs. I'm describing the plumbing from memory. So,

> don't
> > > quote me but I'm pretty sure that's it. The engine runs just fine

> besides
> > > being cold natured. but, it ain't a problem down here in Florida.
> > > All the hoses are in fine shape and I can't find any leaks anywhere.

> I've
> > > torqued the manifolds and they've never leaked either through various

> head
> > > and manifold swaps. The carb's tight too. So, what's the deal with an
> > > otherwise healthy engine that shows good compression. The distributor's

> new
> > > and I've ruled out a ruptured diaphragm. What could it be? Am I being
> > > stupid and there shouldn't be any measured vacuum at idle?
> > > o_o_o_o
> > > Best Regards, /| ,[_____],
> > > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > > ()_)¯()_) ¯¯¯¯¯ )_)
> > > EM60qk 30.447439N 086.628959W


L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III 02-22-2004 11:10 PM

Re: No Measurable Vacuum at Idle???
 
I know I'll get an argument out of Mike Romain here, but manifold
vacuum will get you a better idle and fuel mileage. Try the port over
the number 59 in this view:
http://www.carburetorfactory.com/expvw03.html You might go around it
tightening all the screws, because it should have been easy for you to
find full vacuum, virtually all of them other than the venturi one.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Drink wrote:
>
> You lost me, I think, about where to connect vacuum advance. From the
> passenger side, there are two vacuum ports. At the base, where I'm
> connecting distributor vacuum, is all the way down on the right. About 3/4
> inch higher, to the left is the other. I checked vacuum at both and neither
> presents measurable vacuum but the lower (my connection) provides more
> vacuum at RPM. So, where do you connect?
> What benefit do you get by connecting your way? It seems backwards until
> much higher RPM since you have vacuum advance at idle and then no advance
> upon acceleration. At rev, it sounds like vacuum catches up and you're back
> to where you want to be.
> o_o_o_o
> Best Regards, /| ,[_____],
> Jim, WP3JQ |¯¯¯L --O|||||||O-
> ()_)¯()_) ¯¯¯¯¯ )_)
> EM60qk 30.447439N 086.628959W
> "L.W. (ßill) ------ III" <----------@cox.net> wrote in message
> news:40396F0C.E76FCBD5@cox.net...
> > That's normal and is the venturi vacuum port, the stock and what
> > Mike here likes to hook the distributor diaphragm to, that advances the
> > timing as the engine increases in revolutions per minute. You find full
> > manifold vacuum down at the butterfly throttle plates about fifteen
> > inches of mercury at idle. This port I favor for full advance at idle
> > (makes for smooth idle) yet instantly retards for torque when you stick
> > it, and gradually advances with the centrifugal weights to reach full
> > advance together somewhere between two and three grand.
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
> > Drink wrote:
> > >
> > > Here's something I've pondered for years...
> > > When I tune the Jeep, I have no measurable vacuum at idle. If I raise

> the
> > > RPM above idle around 1,000 and up (revving high), it shows plenty of
> > > vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter

> YF
> > > carb with minimal emissions. In fact, the only thing I have is the

> vacuum
> > > advance ported from the carb, PCV to manifold, canister to manifold and
> > > canister pulling vapor from around the bowl. The intake manifold ports

> were
> > > all plugged with bungs. I'm describing the plumbing from memory. So,

> don't
> > > quote me but I'm pretty sure that's it. The engine runs just fine

> besides
> > > being cold natured. but, it ain't a problem down here in Florida.
> > > All the hoses are in fine shape and I can't find any leaks anywhere.

> I've
> > > torqued the manifolds and they've never leaked either through various

> head
> > > and manifold swaps. The carb's tight too. So, what's the deal with an
> > > otherwise healthy engine that shows good compression. The distributor's

> new
> > > and I've ruled out a ruptured diaphragm. What could it be? Am I being
> > > stupid and there shouldn't be any measured vacuum at idle?
> > > o_o_o_o
> > > Best Regards, /| ,[_____],
> > > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > > ()_)¯()_) ¯¯¯¯¯ )_)
> > > EM60qk 30.447439N 086.628959W


L.W.(=?iso-8859-1?Q?=DFill?=) Hughes III 02-22-2004 11:10 PM

Re: No Measurable Vacuum at Idle???
 
I know I'll get an argument out of Mike Romain here, but manifold
vacuum will get you a better idle and fuel mileage. Try the port over
the number 59 in this view:
http://www.carburetorfactory.com/expvw03.html You might go around it
tightening all the screws, because it should have been easy for you to
find full vacuum, virtually all of them other than the venturi one.
God Bless America, ßill O|||||||O
mailto:-------------------- http://www.----------.com/

Drink wrote:
>
> You lost me, I think, about where to connect vacuum advance. From the
> passenger side, there are two vacuum ports. At the base, where I'm
> connecting distributor vacuum, is all the way down on the right. About 3/4
> inch higher, to the left is the other. I checked vacuum at both and neither
> presents measurable vacuum but the lower (my connection) provides more
> vacuum at RPM. So, where do you connect?
> What benefit do you get by connecting your way? It seems backwards until
> much higher RPM since you have vacuum advance at idle and then no advance
> upon acceleration. At rev, it sounds like vacuum catches up and you're back
> to where you want to be.
> o_o_o_o
> Best Regards, /| ,[_____],
> Jim, WP3JQ |¯¯¯L --O|||||||O-
> ()_)¯()_) ¯¯¯¯¯ )_)
> EM60qk 30.447439N 086.628959W
> "L.W. (ßill) ------ III" <----------@cox.net> wrote in message
> news:40396F0C.E76FCBD5@cox.net...
> > That's normal and is the venturi vacuum port, the stock and what
> > Mike here likes to hook the distributor diaphragm to, that advances the
> > timing as the engine increases in revolutions per minute. You find full
> > manifold vacuum down at the butterfly throttle plates about fifteen
> > inches of mercury at idle. This port I favor for full advance at idle
> > (makes for smooth idle) yet instantly retards for torque when you stick
> > it, and gradually advances with the centrifugal weights to reach full
> > advance together somewhere between two and three grand.
> > God Bless America, ßill O|||||||O
> > mailto:-------------------- http://www.----------.com/
> >
> > Drink wrote:
> > >
> > > Here's something I've pondered for years...
> > > When I tune the Jeep, I have no measurable vacuum at idle. If I raise

> the
> > > RPM above idle around 1,000 and up (revving high), it shows plenty of
> > > vacuum; 16 inches or so I think. I have a '76 258 with the ole' Carter

> YF
> > > carb with minimal emissions. In fact, the only thing I have is the

> vacuum
> > > advance ported from the carb, PCV to manifold, canister to manifold and
> > > canister pulling vapor from around the bowl. The intake manifold ports

> were
> > > all plugged with bungs. I'm describing the plumbing from memory. So,

> don't
> > > quote me but I'm pretty sure that's it. The engine runs just fine

> besides
> > > being cold natured. but, it ain't a problem down here in Florida.
> > > All the hoses are in fine shape and I can't find any leaks anywhere.

> I've
> > > torqued the manifolds and they've never leaked either through various

> head
> > > and manifold swaps. The carb's tight too. So, what's the deal with an
> > > otherwise healthy engine that shows good compression. The distributor's

> new
> > > and I've ruled out a ruptured diaphragm. What could it be? Am I being
> > > stupid and there shouldn't be any measured vacuum at idle?
> > > o_o_o_o
> > > Best Regards, /| ,[_____],
> > > Jim, WP3JQ |¯¯¯L --O|||||||O-
> > > ()_)¯()_) ¯¯¯¯¯ )_)
> > > EM60qk 30.447439N 086.628959W



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