I've moved this topic from the parts for sale forum to the engine forum, it is far too interesting to be lost over in the parts for sale section. I hope this doesn't cause any confusion. keep it up.
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It's funny how the webers appear to come in waves, I know they look awesome, but hear is what I found out about them, They take quite abit of time to dial in and they seem to run differant everyday do to weather condititions,and if you have a new motor I would suggest running a single carb to search out the little bugs and break in. the webers are not something you just bolt on and go, it takes alot of time to get them right for your application, every engine is differant and you need to run them for a period time then make jet changes one at a time. it could run rich or lean at low, medium, high rpm, you have quite a few jets and air jets to consider.
But there is know way anything looks better.
So good luck and happy motoring
Dennis
But there is know way anything looks better.
So good luck and happy motoring
Dennis
Yes to what you said denis. They change with good air and bad air just like a race car does. Jetting on a C is actually very easy. The base line is 140/160 F5. Idles are F.70. I've run with home made .65 idles.
Chokes are about all you need to play with. They come stock with 37mm. Hall only sells them with 32mm. 289 race size is 42mm. I've run as big as 45mm. Mine are 40.5 now but that could change depending on what I'm doing that day.
The Pantera linkage doesn't seem to twist up as bad as other applications but it isn't too unusual to have to re-syn it after running under race conditions for a while. That's not that big a deal.
The problem with the Pantera is how to keep water out of them because they are hagging out on the veranda.
Webers are a way of life.
Chokes are about all you need to play with. They come stock with 37mm. Hall only sells them with 32mm. 289 race size is 42mm. I've run as big as 45mm. Mine are 40.5 now but that could change depending on what I'm doing that day.
The Pantera linkage doesn't seem to twist up as bad as other applications but it isn't too unusual to have to re-syn it after running under race conditions for a while. That's not that big a deal.
The problem with the Pantera is how to keep water out of them because they are hagging out on the veranda.
Webers are a way of life.
My 2 cents !! LOL
I can only say I have tuned them on a friends car many times. They might be a little harder then a 4V carb becaue there are 4 of them instead of 1. Yes the linkage has to be in sinc, but if you ever ran 2 4V's on a V8 these are the same issues. I have them on the 351c they are on the motor let the games begin.
One comment ..... the 4V carb doesnt bolt on out of any box.... the most common mistake ever made with a Holley Carb is its bolted on out of the box.
I think every body should own a Holley carb book. I bought the Weber book and read it. These manuals address many issues besides the induction system.
I can only say I have tuned them on a friends car many times. They might be a little harder then a 4V carb becaue there are 4 of them instead of 1. Yes the linkage has to be in sinc, but if you ever ran 2 4V's on a V8 these are the same issues. I have them on the 351c they are on the motor let the games begin.
One comment ..... the 4V carb doesnt bolt on out of any box.... the most common mistake ever made with a Holley Carb is its bolted on out of the box.
I think every body should own a Holley carb book. I bought the Weber book and read it. These manuals address many issues besides the induction system.
If they are hard to keep tuned they may have the wrong inserts which is common. With correct inserts they should stay reasonably in tune. Like anything else, they have theyer own techniques.
Gary
Gary
Heck why don't you guys just buy the ones that just look like webers but are actually really secret fuel injectors inside?? Then all you gotta do is hook it up to the computer and drive away.
They are more sensative, actually the engine is, because it is an IR and each cylinder has it's own carb. There is no community plenum for them to share and average out the changes.
I always found it interesting that the Holley Carb size chart does not apply to an IR setup. A typical set of 48IDA's is flowing around 2400cfm.
They are also very sensative to reverberation in the manifold. If you are going to seriously try to tune them you should limit the cam overlap to 30 to 35 degrees. In other words a special "weber cam".
Big overlap cams don't work well with them. The overlap on the exhaust actually reverses the flow of the carb and blows it back out of the stack.
Another caution, make sure that you use high pressure fuel inlet valves, low fuel pressure (3psi) and heat isolating gaskets. If you don't when you shut the enging off hot, the fuel will perkulate like in a coffee pot and turn into "old faithful", the geiser.
Want to see your hot engine swimming is gas? It'll take years off of your life.
I'm sure there are a couple of little things I left out but you'll have a wonderful time experiencing the wonderful world of weber on your own. Enjoy!
I always found it interesting that the Holley Carb size chart does not apply to an IR setup. A typical set of 48IDA's is flowing around 2400cfm.
They are also very sensative to reverberation in the manifold. If you are going to seriously try to tune them you should limit the cam overlap to 30 to 35 degrees. In other words a special "weber cam".
Big overlap cams don't work well with them. The overlap on the exhaust actually reverses the flow of the carb and blows it back out of the stack.
Another caution, make sure that you use high pressure fuel inlet valves, low fuel pressure (3psi) and heat isolating gaskets. If you don't when you shut the enging off hot, the fuel will perkulate like in a coffee pot and turn into "old faithful", the geiser.
Want to see your hot engine swimming is gas? It'll take years off of your life.
I'm sure there are a couple of little things I left out but you'll have a wonderful time experiencing the wonderful world of weber on your own. Enjoy!
What would life be without things to tackle right?!
Gary
Gary
...it's called pressure, I actually can do without it.
Well, I have had mine running on the car for 5 months and I have them working pretty well, They seem to run a little differant each day depending on the weather, but its worth it. they look and sound awesome.
Good Luck Guys
Dennis
Good Luck Guys
Dennis
They take just a bit of getting used to. I think that they are infectous like Malaria. You think that you are over them and suddenly the fever reappears.
I will never get used to the exhaust popping when you step off and brake hard. That can be a little unnerving and startling to unwary bystanders.
I will never get used to the exhaust popping when you step off and brake hard. That can be a little unnerving and startling to unwary bystanders.
Pantera Doug,
Couple questions if you dont mind ?
"Third Progression Hole Modification" Is recommend as a modification to IDA's that are going to be used on street engines, since it makes them significantly more drivable, have you ever done this ?
You stated "high pressure fuel inlet valves" ? On holleys these check valves can be installed in place of the little filter in the carb, where would these go, is there a place in the weber or are they an inline item ? Or is one installed on the main feed with the regulator ?
Thanks,
Ron
Couple questions if you dont mind ?
"Third Progression Hole Modification" Is recommend as a modification to IDA's that are going to be used on street engines, since it makes them significantly more drivable, have you ever done this ?
You stated "high pressure fuel inlet valves" ? On holleys these check valves can be installed in place of the little filter in the carb, where would these go, is there a place in the weber or are they an inline item ? Or is one installed on the main feed with the regulator ?
Thanks,
Ron
I'm enjoying your banter back & forth guys.
I think Dennis has the right attitude. They look bitchen, they sound bitchen, the throttle response is bitchen, but they are fussy. NO body using them has said they aren't. You say it different ways. But they're fussy.
Webers are like a religion. Of course, the adherents of some religions beat themselves with chains too! Others handle rattle snakes. You get the picture.
I have a picture of Dennis' motor pinned next to my bed! lol....You should hear it, man, with those 180s & those Webers, it wails! I had to take a cold shower after hearing his car run. I've never met a woman that excites me that much.
But I'm glad it's his car with those Webers & not mine. lol......
George
I think Dennis has the right attitude. They look bitchen, they sound bitchen, the throttle response is bitchen, but they are fussy. NO body using them has said they aren't. You say it different ways. But they're fussy.
Webers are like a religion. Of course, the adherents of some religions beat themselves with chains too! Others handle rattle snakes. You get the picture.
I have a picture of Dennis' motor pinned next to my bed! lol....You should hear it, man, with those 180s & those Webers, it wails! I had to take a cold shower after hearing his car run. I've never met a woman that excites me that much.
But I'm glad it's his car with those Webers & not mine. lol......
George
I think it would be a good topic of discussion George on the engine forum.
I have briefly written about Webers a couple of times in the past. Perhaps one of you guys who have owned them for a long term would like to write a Weber essay for the Bulletin Board?
George
George
I have had Webers since 1981 and been very pleased with them under almost all circumstances other than high altitude conditions when they perform poorly and you have lots of glorious black smoke pouring out. Webers are not for everybody. Having to notch out your rear decklid is too much for some owner's to handle for starters. The most concerning thing for me is the increased fire hazard. I do have a Halon system and have actually had to deploy it once.
Be mindful that four Weber 2-bbl carburetors offers more CFM than you can imagine, in my case 2600 CFM. When some owners are noting that a 850 Holley is too big, imagine having the Webers to dial in.
Cam selection is crucial and the overlap problem earlier noted is for real. Since a Weber manifold doesn't have a plenum, excess fuel has nowhere to go but up into the "stand-off" plume which is obviously quite flammable.
Having suffered two air cleaner based fires when the stand-off ignites, I no longer run with air cleaners. Fire proof air cleaners won't prevent a fire but only provide less fuel for the fire. I am always alert and vigilant and watch in my rear view mirror, just to be safe.
I am fortunate to have crossed paths with Augie Delgado in Orange County who took my Webers to the next level. He tunes the carburetors every two years.
I have ridden in all types of Panteras from single carbs to multiple carbs to forced induction and nitrous on tap. I favor Webers for my use because of the look, the sound and the instant power, especially when exiting a turn.
I would not recommend Webers to an owner that is looking for a seamless installation and operation. We have taken off more Weber set-ups than installed them.
Since my car was raced with Webers, historically, I have sympatico with them. Since this is an expensive modification, be sure you know what you want and that you have good technical help to get you through the learning curve.
Finally, most Weber owners have a similar experience to my own with a flat spot at a varying RPM range or "transition". I consider this trivial and simply have gotten used to it. With my present configuration, no amount of tuning will dispell it.
Respectfully,
Dave
Be mindful that four Weber 2-bbl carburetors offers more CFM than you can imagine, in my case 2600 CFM. When some owners are noting that a 850 Holley is too big, imagine having the Webers to dial in.
Cam selection is crucial and the overlap problem earlier noted is for real. Since a Weber manifold doesn't have a plenum, excess fuel has nowhere to go but up into the "stand-off" plume which is obviously quite flammable.
Having suffered two air cleaner based fires when the stand-off ignites, I no longer run with air cleaners. Fire proof air cleaners won't prevent a fire but only provide less fuel for the fire. I am always alert and vigilant and watch in my rear view mirror, just to be safe.
I am fortunate to have crossed paths with Augie Delgado in Orange County who took my Webers to the next level. He tunes the carburetors every two years.
I have ridden in all types of Panteras from single carbs to multiple carbs to forced induction and nitrous on tap. I favor Webers for my use because of the look, the sound and the instant power, especially when exiting a turn.
I would not recommend Webers to an owner that is looking for a seamless installation and operation. We have taken off more Weber set-ups than installed them.
Since my car was raced with Webers, historically, I have sympatico with them. Since this is an expensive modification, be sure you know what you want and that you have good technical help to get you through the learning curve.
Finally, most Weber owners have a similar experience to my own with a flat spot at a varying RPM range or "transition". I consider this trivial and simply have gotten used to it. With my present configuration, no amount of tuning will dispell it.
Respectfully,
Dave
An essay? Who is going to grade it? Why don't we just discuss them here? Or is that disgust them? Maybe if we talk about Webers here, someone will actually buy this guys setup from this classified ad?
To answer your questions ACCobra I know about the third transition hole modification. I personally wouldn't buy an IDA if I know it has it.
Webers are already, very, very streetable. It's the engine that is finaky with this much carburetion.
The modification, to try to put it in a nut shell, is to correct or overcome what the "Weber guys" call "the transition flat spot". Some days it's there some days no.
It shows itself generally between 2800 rpm and 3000 rpms.
The carbs are essentially running on the idle circuit to about 3000 rpm in a 48ida. This is the point that the main circuit starts to take effect.
Some days the idle makes it to 3000 some days it doesn't.
You may already know that the main circuit has a fuel jet an air jet and an emmulsion tube.
They are all changeable. The 351c likes a 140f, 160a and an F5 tube.
The most important of these three components are the fuel jet and air jet. They need to be kept in the same proportion when making changes, generally speaking. What the emulsion tube does is effect the strength of the air/fuel ratio at different engine rpms. It does this by reacting to vacuum drop through key located orafices in the carburetor.
The idle system in the IDA can only have the fuel jet changed in order to affect the strength of the circuit. One cannot change the air jet or the emmulsion tube for the idle circuit. It doesn't really have one, it's an idle jet holder.
That is the problem that creates the flat spot.
The fuel jet is plenty large enough but the "idle jet holder" is letting the mixture lean out "SOMETIMES". (air temp, humidity, altitude, barometric pressure all effect it). Racers just shorten it and say good air or bad air.
The third hole tries to fix this by giving more fuel at a cirtain throttle position but it doesn't need more fuel there, it needs a stronger mixture. There is a big difference.
If it was the main circuit we could try the various emullsion tubes until we found one better suited to richening the last 200rpm. In the idle circuit you can't. It isn't the quantity of the fuel that is causing the problem it is the strength of the emullsion.
What is the emullsion? Fuel itself won't combust. It needs to be mixed with air, oxygen specifically (that's in our air).
Stoiochemic (perfect chemical ratio for emissions) is 14.7:1. (sorry I don't spell real good, gosh golly!) The larger number is the portion of air and the one is the fuel. Fuel becomes volitile (explosive) at 20:1. Power in american v-8s is thought to be optimum at 12.9:1. You couldn't race at 14.7. If you could wind it up you would put a hole in a piston or burn it or the valves or do something really bad to the engine.
What "we" are doing with the jets and emulsion tubes is mechanically writing a fuel graph as close to optimum as our butts will inform us of.
Computer controlled cars can be programed to read a script much closer to what we can do mechanically. Frankly they rarely do.
Of course if you want to go on a dyno, hook it to an exhaust analizer and a computer that can load the drive train to simulated the course you are optimizing for, you could probably elliminate a lot of redundancey. It would certainly get you to a point at which I just put you here with the Webers for free. Of course you wouldn't be a real Weber person either.
I don't know if the "transition" can ever be completely eliminated. Not until someone wants to try to do a new idle jet holder for the IDA.
...and like Bob Dylan says in the song, "it ain't me babe!"
You asked another question too, but what was it? huh?
Barkeep, a couple of Buttery Nipples please!
To answer your questions ACCobra I know about the third transition hole modification. I personally wouldn't buy an IDA if I know it has it.
Webers are already, very, very streetable. It's the engine that is finaky with this much carburetion.
The modification, to try to put it in a nut shell, is to correct or overcome what the "Weber guys" call "the transition flat spot". Some days it's there some days no.
It shows itself generally between 2800 rpm and 3000 rpms.
The carbs are essentially running on the idle circuit to about 3000 rpm in a 48ida. This is the point that the main circuit starts to take effect.
Some days the idle makes it to 3000 some days it doesn't.
You may already know that the main circuit has a fuel jet an air jet and an emmulsion tube.
They are all changeable. The 351c likes a 140f, 160a and an F5 tube.
The most important of these three components are the fuel jet and air jet. They need to be kept in the same proportion when making changes, generally speaking. What the emulsion tube does is effect the strength of the air/fuel ratio at different engine rpms. It does this by reacting to vacuum drop through key located orafices in the carburetor.
The idle system in the IDA can only have the fuel jet changed in order to affect the strength of the circuit. One cannot change the air jet or the emmulsion tube for the idle circuit. It doesn't really have one, it's an idle jet holder.
That is the problem that creates the flat spot.
The fuel jet is plenty large enough but the "idle jet holder" is letting the mixture lean out "SOMETIMES". (air temp, humidity, altitude, barometric pressure all effect it). Racers just shorten it and say good air or bad air.
The third hole tries to fix this by giving more fuel at a cirtain throttle position but it doesn't need more fuel there, it needs a stronger mixture. There is a big difference.
If it was the main circuit we could try the various emullsion tubes until we found one better suited to richening the last 200rpm. In the idle circuit you can't. It isn't the quantity of the fuel that is causing the problem it is the strength of the emullsion.
What is the emullsion? Fuel itself won't combust. It needs to be mixed with air, oxygen specifically (that's in our air).
Stoiochemic (perfect chemical ratio for emissions) is 14.7:1. (sorry I don't spell real good, gosh golly!) The larger number is the portion of air and the one is the fuel. Fuel becomes volitile (explosive) at 20:1. Power in american v-8s is thought to be optimum at 12.9:1. You couldn't race at 14.7. If you could wind it up you would put a hole in a piston or burn it or the valves or do something really bad to the engine.
What "we" are doing with the jets and emulsion tubes is mechanically writing a fuel graph as close to optimum as our butts will inform us of.
Computer controlled cars can be programed to read a script much closer to what we can do mechanically. Frankly they rarely do.
Of course if you want to go on a dyno, hook it to an exhaust analizer and a computer that can load the drive train to simulated the course you are optimizing for, you could probably elliminate a lot of redundancey. It would certainly get you to a point at which I just put you here with the Webers for free. Of course you wouldn't be a real Weber person either.
I don't know if the "transition" can ever be completely eliminated. Not until someone wants to try to do a new idle jet holder for the IDA.
...and like Bob Dylan says in the song, "it ain't me babe!"
You asked another question too, but what was it? huh?
Barkeep, a couple of Buttery Nipples please!
I say PD and Whiplash ..... I do say thanks and I would like to be able to consult with you guys if thats OK ?
But I feel with my experience with Racing Cars and 22 of Mechanical Systems... LOL I think I'm ready to give it a shot..... and Whiplash a halon system would probably not be a bad idea...and yes I have installed them in a Methane Plant in the Bronx.
Couple minor questions to start.
1. Cam ? any specs. the motor is a fresh rebuilt 351C basically stock I choose this route since I'm having another one built as we speak, but would like the learning curve to be on this one.
2. PD this is for you ? Do those specs for Mai Jet, Air Jet and ET apply for a stock motor, I ask for this only to establish a base line to start.
3. As I asked before ? The high pressure fuel inlet valves ( check valves ) point me in the right direction ?
4. Fuel pump ? you recommend manual set to 3psi ?
5. Linkage seems straight foward ? Vacumm for the breaks...simple plumbing SWAGELOCK SS fittings.
6. Gaskets for non transfer of heat.. point well taken.
Last but not least .... have we anyone here in NY to help me tune this car... you sound like a good canidate ??? LOL
I have to ask for your email PD ?
I know all the weber talk is a little discouraging at times, but I dont discourage easy.... but who knows maybe you will say some day I told you soooo. That wont be the first time either... LOL
Again THANKS GUYS I LOVE YA !!!
But I feel with my experience with Racing Cars and 22 of Mechanical Systems... LOL I think I'm ready to give it a shot..... and Whiplash a halon system would probably not be a bad idea...and yes I have installed them in a Methane Plant in the Bronx.
Couple minor questions to start.
1. Cam ? any specs. the motor is a fresh rebuilt 351C basically stock I choose this route since I'm having another one built as we speak, but would like the learning curve to be on this one.
2. PD this is for you ? Do those specs for Mai Jet, Air Jet and ET apply for a stock motor, I ask for this only to establish a base line to start.
3. As I asked before ? The high pressure fuel inlet valves ( check valves ) point me in the right direction ?
4. Fuel pump ? you recommend manual set to 3psi ?
5. Linkage seems straight foward ? Vacumm for the breaks...simple plumbing SWAGELOCK SS fittings.
6. Gaskets for non transfer of heat.. point well taken.
Last but not least .... have we anyone here in NY to help me tune this car... you sound like a good canidate ??? LOL
I have to ask for your email PD ?
I know all the weber talk is a little discouraging at times, but I dont discourage easy.... but who knows maybe you will say some day I told you soooo. That wont be the first time either... LOL
Again THANKS GUYS I LOVE YA !!!
Mark, your the best .... you got me into this mess ... !! LOL just joking ... and who are they ?? my email ronmarl@optonline.net or post it here if you prefer ? Thanks Mark.
Ron
Ron
You don't luv us, trust me, it's the Buttery Nipples talking.
You can email me at hammer99@erols.com.
Me personally, I don't see any point in a hydraulic lifter CJ with Webers. They are for performance. You run a solid lifter, triple valve spring, titanium valves, high compression engine (rev limiter is a great idea incidentally). I don't agree with anyone who puts them on JUST for looks. That's rediculous. That's like buying a nuclear device because you like the black paint on it.
Webers aren't necessarily faster off the line, but they are better then anything I have ever driven coming out of a turn and they play over 100 like...well you have to experience that to believe it. I rember putting 10 lengths on a supercharged 66 GT350 and I was waiting for him.
I got a glimse of him beating the steering wheel with both hands to make it go faster... but back to your questions.
The 140 main is more representative to the size of the engine more then anything else. 289's take 125/215's. It will run on a box stock CJ cleanly. You can idle them down to a 125 m (with proportionate air corrector) and pretty much be limited to about 5500 rpm like a rev limiter. The F5 would stay the same. You coud use 65 idles on that one also.
You also need to get a unisync. You can't work without them. Idle screws should be between 1/2 turn and 3/4 turn out. I like about 5/8.
The size of the chokes is more signifigant to your useage and capabilaty of the engine then anything.
You can use 32mm (custom made for you) like Hall does. That's the most you should close them down. Personally I think thats a waste of carburetors.
I'd recommend useing the stock 37mm and go up as you feel. 42mm will change the entire nature of the carb and engine and move the torque peak up.
You could prove that you lost torque by that move but not by me.
A 42mm choke engine means that you flat out whale on it, no holds barred.
If you assemble all the parts we suggested, can bolt the thing together, and adjust the linkage with the unisync then you really don't need much help from me. You have been granted the knowledge of the ages, I certainly don't know much more about them.
I do recommend that you do use a manifold with the center pivot tower like Hall makes for the Pantera. It works great with the Pantera's stock pull throttle cable.
The side pivot would be for a C in another chassis like the Mustang. A lot of these manifolds are modified Hall manifolds. The Mustang guys like to mill the tower out and grind Hall Pantera off of it.
Inglese Inductions is right near us in CT. His prices on the parts you need are as good as anyone else and he's got everything that you need.
Also, count on needing the hottest ignition you can put in the car. There is just a "little" tendancy to foul the plugs.
As far as tuning your car? With all due respect, I'm way over my head with what I've got already.
With any luck I should be done with my stuff by the next millenium... hopefully.
I'm only on the Net 'cause it's my form of group therapy ( and cheaper).
You can email me at hammer99@erols.com.
Me personally, I don't see any point in a hydraulic lifter CJ with Webers. They are for performance. You run a solid lifter, triple valve spring, titanium valves, high compression engine (rev limiter is a great idea incidentally). I don't agree with anyone who puts them on JUST for looks. That's rediculous. That's like buying a nuclear device because you like the black paint on it.
Webers aren't necessarily faster off the line, but they are better then anything I have ever driven coming out of a turn and they play over 100 like...well you have to experience that to believe it. I rember putting 10 lengths on a supercharged 66 GT350 and I was waiting for him.
I got a glimse of him beating the steering wheel with both hands to make it go faster... but back to your questions.
The 140 main is more representative to the size of the engine more then anything else. 289's take 125/215's. It will run on a box stock CJ cleanly. You can idle them down to a 125 m (with proportionate air corrector) and pretty much be limited to about 5500 rpm like a rev limiter. The F5 would stay the same. You coud use 65 idles on that one also.
You also need to get a unisync. You can't work without them. Idle screws should be between 1/2 turn and 3/4 turn out. I like about 5/8.
The size of the chokes is more signifigant to your useage and capabilaty of the engine then anything.
You can use 32mm (custom made for you) like Hall does. That's the most you should close them down. Personally I think thats a waste of carburetors.
I'd recommend useing the stock 37mm and go up as you feel. 42mm will change the entire nature of the carb and engine and move the torque peak up.
You could prove that you lost torque by that move but not by me.
A 42mm choke engine means that you flat out whale on it, no holds barred.
If you assemble all the parts we suggested, can bolt the thing together, and adjust the linkage with the unisync then you really don't need much help from me. You have been granted the knowledge of the ages, I certainly don't know much more about them.
I do recommend that you do use a manifold with the center pivot tower like Hall makes for the Pantera. It works great with the Pantera's stock pull throttle cable.
The side pivot would be for a C in another chassis like the Mustang. A lot of these manifolds are modified Hall manifolds. The Mustang guys like to mill the tower out and grind Hall Pantera off of it.
Inglese Inductions is right near us in CT. His prices on the parts you need are as good as anyone else and he's got everything that you need.
Also, count on needing the hottest ignition you can put in the car. There is just a "little" tendancy to foul the plugs.
As far as tuning your car? With all due respect, I'm way over my head with what I've got already.
With any luck I should be done with my stuff by the next millenium... hopefully.
I'm only on the Net 'cause it's my form of group therapy ( and cheaper).