Vizard's LSA - CI/Inch Valve Diameter chart
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Obviously you are not familar with all the drilling modifing jetting pump adjusting etc.
Originally Posted by 1997bird
No, that is usually operator error. Nobody really knows how to work on them anymore, b/c everything has went to some form of injection over the last 19 yrs.
Originally Posted by LS1curious
Obviously you are not familar with all the drilling modifing jetting pump adjusting etc.
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I dunno I work on a blow through carbed 468 going mid 8's so maybe I know what I am talking about.
Originally Posted by 1997bird
I have no problems with my carbed motors and tuning them properly. I was stating that most people can't tune their combo's properly anymore, b/c of the popularity of fuel injection and the lack of people useing carb's today. That is where your statement about the carb's comes into play.......or is it you that can't get a carb to run right?
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How much oil do they consume on average ? There would be my idea of running like ****. You can make them drive nice but you will always have a spot in the curve where its to rich and it will wash the rings down and create oil consumption.
This would be why the Big 3 and all the foriegn manufacturers went to EFI in the first place. Reducded ring wear due to fuel wash secondly fuel control for emissions reasons.
.
You can make make a carbed car drive nice but it'll never be anywhere as good as an efi car at fuel control.
And the carbs go marching on.
This would be why the Big 3 and all the foriegn manufacturers went to EFI in the first place. Reducded ring wear due to fuel wash secondly fuel control for emissions reasons.
.
You can make make a carbed car drive nice but it'll never be anywhere as good as an efi car at fuel control.
And the carbs go marching on.
Originally Posted by edcmat-l1
Oh, but I am. And none of my carbed engines run like dog ****.
Originally Posted by LS1curious
How much oil do they consume on average ? There would be my idea of running like ****. You can make them drive nice but you will always have a spot in the curve where its to rich and it will wash the rings down and create oil consumption.
This would be why the Big 3 and all the foriegn manufacturers went to EFI in the first place. Reducded ring wear due to fuel wash secondly fuel control for emissions reasons.
.
You can make make a carbed car drive nice but it'll never be anywhere as good as an efi car at fuel control.
And the carbs go marching on.
This would be why the Big 3 and all the foriegn manufacturers went to EFI in the first place. Reducded ring wear due to fuel wash secondly fuel control for emissions reasons.
.
You can make make a carbed car drive nice but it'll never be anywhere as good as an efi car at fuel control.
And the carbs go marching on.
The only time it would be that rich would be either an accelerator pump shot, or the PV opening. Both of which (esp pump shot) are mechanical 'cover ups' for 2nd or 3rd circuits that arent working right.
The more 'sensitive' the main circuits are, the less of a pump shot you need.
Most people up the pump shot with bigger squirters, or bigger CC pumps, or both. I increase the sensitivity of the main circuit, or booster. How? Well, I could tell you, but I'd have to kill you!
So, back to the original topic. Carbs, set up right, are more forgiving than EFI.
The BIG 3 never intended EFI to control engines with 8 in of manifold vacuum, driving around at 1400 rpms.
[QUOTE=LS1curious]How much oil do they consume on average ? There would be my idea of running like ****. [QUOTE]
I don't know about that, I have tuned circle track "Modified's" that are on methanol and run at 7k+ most all of the time on the track. My combo's are running for a full season without blowby on the valve cover breather's. I have several motors that have two full season's on them without having to tear them down at all. They will be refreashed at the end of this season, as the blowby is starting to get progressively worse. These cars that I am talking about are in the top 6 this year for the points lead on their 46+ race engine's. I may not be the smartest guy in the automotive industry, but I am smart enough to know that you don't make blanket statements about all carb'd motors run like dogshit. If that was the case I guess all of the NHRA race team's have crappy running carb motors too.
I don't know about that, I have tuned circle track "Modified's" that are on methanol and run at 7k+ most all of the time on the track. My combo's are running for a full season without blowby on the valve cover breather's. I have several motors that have two full season's on them without having to tear them down at all. They will be refreashed at the end of this season, as the blowby is starting to get progressively worse. These cars that I am talking about are in the top 6 this year for the points lead on their 46+ race engine's. I may not be the smartest guy in the automotive industry, but I am smart enough to know that you don't make blanket statements about all carb'd motors run like dogshit. If that was the case I guess all of the NHRA race team's have crappy running carb motors too.
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the fact is that you'll never get a carb 100% right ever. If you could they would still come on new cars. there is no point in continuing the discussion becuase the case was closed on this long ago.
Metering circut senstitivty isn;t your issue. Try instead on graphing up your AF across various RPM and Load ranges. You see what I am talking about.
Metering circut senstitivty isn;t your issue. Try instead on graphing up your AF across various RPM and Load ranges. You see what I am talking about.
Originally Posted by edcmat-l1
If you're washing, rings you're carb is not right, point blank. To wash out rings, it would have to off considerably.
The only time it would be that rich would be either an accelerator pump shot, or the PV opening. Both of which (esp pump shot) are mechanical 'cover ups' for 2nd or 3rd circuits that arent working right.
The more 'sensitive' the main circuits are, the less of a pump shot you need.
Most people up the pump shot with bigger squirters, or bigger CC pumps, or both. I increase the sensitivity of the main circuit, or booster. How? Well, I could tell you, but I'd have to kill you!
So, back to the original topic. Carbs, set up right, are more forgiving than EFI.
The BIG 3 never intended EFI to control engines with 8 in of manifold vacuum, driving around at 1400 rpms.
The only time it would be that rich would be either an accelerator pump shot, or the PV opening. Both of which (esp pump shot) are mechanical 'cover ups' for 2nd or 3rd circuits that arent working right.
The more 'sensitive' the main circuits are, the less of a pump shot you need.
Most people up the pump shot with bigger squirters, or bigger CC pumps, or both. I increase the sensitivity of the main circuit, or booster. How? Well, I could tell you, but I'd have to kill you!
So, back to the original topic. Carbs, set up right, are more forgiving than EFI.
The BIG 3 never intended EFI to control engines with 8 in of manifold vacuum, driving around at 1400 rpms.
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Originally Posted by LS1curious
the fact is that you'll never get a carb 100% right ever. If you could they would still come on new cars. there is no point in continuing the discussion becuase the case was closed on this long ago.
Metering circut senstitivty isn;t your issue. Try instead on graphing up your AF across various RPM and Load ranges. You see what I am talking about.
Metering circut senstitivty isn;t your issue. Try instead on graphing up your AF across various RPM and Load ranges. You see what I am talking about.
You stated some crap about washing rings. I stated if you were washing rings your carb is wacked.
Now you wanna make it about graphing A/F across the entire MAP/RPM table.
You're pulling **** out your ***. You're not gonna have a carb, thats damn close for the most part, rich enough in the zones where its not close, to cause any type of ring wash.
I got alot of respect for you, but sometimes you just talk **** to be argumentative.
You aint talkin to some punk kid whos got a buddy wit a dis or dat. I've tuned, wrenched, built, assisted on TS cars, alcohol funnys, etc. Upwards of 2000 hp.
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From: Norn Iron
Originally Posted by edcmat-l1
I said they were more forgiving than EFI on radical cam engines.
When a carb relies totally in intake manifold vacuum present, a radical cam can **** this up entirely with very poor vacuum signal.
A modern efi system can be tuned, with total disregard to manifold vacuum, which means you can tune it pretty much perfectly, and easily everywhere, regardless of how big or small a cam is.
When people started switching from carbs to efi, this was one of its biggest assets. The ability to smooth and tame what were previously horrible cams to use down low.
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I can get EFI to run on **** a carb wouldn't have a prayer at. I have run EFI with zero idle vacum. Alpha-N blending is a thing of beauty.
And yes you will have metering issue across load RPM ranges. No matter how sophisticated your carb is its still a beer can full of gas with a straw in it.
there are also sevral SAE papers on this discussion and the studys that they did. go read some papers on ring wash and engine life come back here and we can disucss this on the same footing.
And yes you will have metering issue across load RPM ranges. No matter how sophisticated your carb is its still a beer can full of gas with a straw in it.
there are also sevral SAE papers on this discussion and the studys that they did. go read some papers on ring wash and engine life come back here and we can disucss this on the same footing.
Originally Posted by edcmat-l1
I never said you could get a carb 100% perfect. I said they were more forgiving than EFI on radical cam engines. And they are.
You stated some crap about washing rings. I stated if you were washing rings your carb is wacked.
Now you wanna make it about graphing A/F across the entire MAP/RPM table.
You're pulling **** out your ***. You're not gonna have a carb, thats damn close for the most part, rich enough in the zones where its not close, to cause any type of ring wash.
I got alot of respect for you, but sometimes you just talk **** to be argumentative.
You aint talkin to some punk kid whos got a buddy wit a dis or dat. I've tuned, wrenched, built, assisted on TS cars, alcohol funnys, etc. Upwards of 2000 hp.
You stated some crap about washing rings. I stated if you were washing rings your carb is wacked.
Now you wanna make it about graphing A/F across the entire MAP/RPM table.
You're pulling **** out your ***. You're not gonna have a carb, thats damn close for the most part, rich enough in the zones where its not close, to cause any type of ring wash.
I got alot of respect for you, but sometimes you just talk **** to be argumentative.
You aint talkin to some punk kid whos got a buddy wit a dis or dat. I've tuned, wrenched, built, assisted on TS cars, alcohol funnys, etc. Upwards of 2000 hp.
Blah, Blah, Blah.
Carbs are more forgiving. Alpha-N or not. And you aint tunin no **** with no idle vacuum.
And believe me, I've cleaned up more tunes than I can count. Idle problems, surge problems, **** others cant seem to figure out. Even 'well known' tuners.
Carbs are not near as sensitve as EFI is. Even with very low vacuum, and lots of intake reversion.
And just from a pure performance standpoint, why has Harold Martins EFI NOS Pro Mod never been able to keep up with the Carb cars? Hes got all the backing in the world.
I'm not an EFI critic. I love EFI. I'm an electronics guy for the past 15 plus years. But I know their limitations.
I've tuned some of the craziest **** out there. And I know what works and what doesnt. And what you can get away with and what not.
Your analogy of a carb being a 'can of gas with a straw in it' explains your misunderstanding of the level of technology of carburators these days.
Carbs are more forgiving. Alpha-N or not. And you aint tunin no **** with no idle vacuum.
And believe me, I've cleaned up more tunes than I can count. Idle problems, surge problems, **** others cant seem to figure out. Even 'well known' tuners.
Carbs are not near as sensitve as EFI is. Even with very low vacuum, and lots of intake reversion.
And just from a pure performance standpoint, why has Harold Martins EFI NOS Pro Mod never been able to keep up with the Carb cars? Hes got all the backing in the world.
I'm not an EFI critic. I love EFI. I'm an electronics guy for the past 15 plus years. But I know their limitations.
I've tuned some of the craziest **** out there. And I know what works and what doesnt. And what you can get away with and what not.
Your analogy of a carb being a 'can of gas with a straw in it' explains your misunderstanding of the level of technology of carburators these days.
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From: Norn Iron
Originally Posted by edcmat-l1
Blah, Blah, Blah.
Carbs are more forgiving. Alpha-N or not. And you aint tunin no **** with no idle vacuum.
Carbs are more forgiving. Alpha-N or not. And you aint tunin no **** with no idle vacuum.
But defo cases where vacuum is very low. I can only think, that if you think carbs are easier...you must be trying to tune with a calculator. Because it sure isnt a modern efi system !!
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hmm I think you don't understand highoutput 4cylinder ITB stuff. 90 kpa idle on its best day.
No matter what you do to a carburator it'll never be anything beyond a gas can with a straw sticking out of it period.
You can add a ton of air bleeding and emulsifiying orifices and circuts you can redesign the discharge orifices all day but its doesn't change that fact ever. A carberator is a pressure differential device. No pressure difference no function. Sure a carb can tolerate low idle vacum becuase the venturi it self genrates Some of the signal. but as soon as that fuel hits the plenum it falls right out of suspension.
we have a huge difference between a Electronics guy and someone who does what he talks about for a living. Honestly the EFI system is not holding the EFI pro-mod back. Something else in the system is.Could be the ratting for flow on the TB's honestly. You have one TB with a rating at 1.5 inchs of mercury and another at 28inch of water deprssion. You also have a laminar flow elemnt in the carberator which is the venturi itself the helps drive airflow through the plate.
but I am done with this topic. EFI wins if carbs are so great why is proof is in the pudding. F1 runs EFI. if a carb had an advatage I think the companies spending millions daily to find HP would be all over it.
If you want to talk fankly about fuel atomoization differences between carberators and EFI glad to have that discussion.
No matter what you do to a carburator it'll never be anything beyond a gas can with a straw sticking out of it period.
You can add a ton of air bleeding and emulsifiying orifices and circuts you can redesign the discharge orifices all day but its doesn't change that fact ever. A carberator is a pressure differential device. No pressure difference no function. Sure a carb can tolerate low idle vacum becuase the venturi it self genrates Some of the signal. but as soon as that fuel hits the plenum it falls right out of suspension.
we have a huge difference between a Electronics guy and someone who does what he talks about for a living. Honestly the EFI system is not holding the EFI pro-mod back. Something else in the system is.Could be the ratting for flow on the TB's honestly. You have one TB with a rating at 1.5 inchs of mercury and another at 28inch of water deprssion. You also have a laminar flow elemnt in the carberator which is the venturi itself the helps drive airflow through the plate.
but I am done with this topic. EFI wins if carbs are so great why is proof is in the pudding. F1 runs EFI. if a carb had an advatage I think the companies spending millions daily to find HP would be all over it.
If you want to talk fankly about fuel atomoization differences between carberators and EFI glad to have that discussion.
Originally Posted by edcmat-l1
Blah, Blah, Blah.
Carbs are more forgiving. Alpha-N or not. And you aint tunin no **** with no idle vacuum.
And believe me, I've cleaned up more tunes than I can count. Idle problems, surge problems, **** others cant seem to figure out. Even 'well known' tuners.
Carbs are not near as sensitve as EFI is. Even with very low vacuum, and lots of intake reversion.
And just from a pure performance standpoint, why has Harold Martins EFI NOS Pro Mod never been able to keep up with the Carb cars? Hes got all the backing in the world.
I'm not an EFI critic. I love EFI. I'm an electronics guy for the past 15 plus years. But I know their limitations.
I've tuned some of the craziest **** out there. And I know what works and what doesnt. And what you can get away with and what not.
Your analogy of a carb being a 'can of gas with a straw in it' explains your misunderstanding of the level of technology of carburators these days.
Carbs are more forgiving. Alpha-N or not. And you aint tunin no **** with no idle vacuum.
And believe me, I've cleaned up more tunes than I can count. Idle problems, surge problems, **** others cant seem to figure out. Even 'well known' tuners.
Carbs are not near as sensitve as EFI is. Even with very low vacuum, and lots of intake reversion.
And just from a pure performance standpoint, why has Harold Martins EFI NOS Pro Mod never been able to keep up with the Carb cars? Hes got all the backing in the world.
I'm not an EFI critic. I love EFI. I'm an electronics guy for the past 15 plus years. But I know their limitations.
I've tuned some of the craziest **** out there. And I know what works and what doesnt. And what you can get away with and what not.
Your analogy of a carb being a 'can of gas with a straw in it' explains your misunderstanding of the level of technology of carburators these days.
Originally Posted by stevieturbo
If there was no vacuum...I guess the engine probably wouldnt be running lol, so thats maybe an extreme example.
But defo cases where vacuum is very low. I can only think, that if you think carbs are easier...you must be trying to tune with a calculator. Because it sure isnt a modern efi system !!
But defo cases where vacuum is very low. I can only think, that if you think carbs are easier...you must be trying to tune with a calculator. Because it sure isnt a modern efi system !!
Originally Posted by LS1curious
hmm I think you don't understand highoutput 4cylinder ITB stuff. 90 kpa idle on its best day.
No matter what you do to a carburator it'll never be anything beyond a gas can with a straw sticking out of it period.
You can add a ton of air bleeding and emulsifiying orifices and circuts you can redesign the discharge orifices all day but its doesn't change that fact ever. A carberator is a pressure differential device. No pressure difference no function. Sure a carb can tolerate low idle vacum becuase the venturi it self genrates Some of the signal. but as soon as that fuel hits the plenum it falls right out of suspension.
we have a huge difference between a Electronics guy and someone who does what he talks about for a living. Honestly the EFI system is not holding the EFI pro-mod back. Something else in the system is.Could be the ratting for flow on the TB's honestly. You have one TB with a rating at 1.5 inchs of mercury and another at 28inch of water deprssion. You also have a laminar flow elemnt in the carberator which is the venturi itself the helps drive airflow through the plate.
but I am done with this topic. EFI wins if carbs are so great why is proof is in the pudding. F1 runs EFI. if a carb had an advatage I think the companies spending millions daily to find HP would be all over it.
If you want to talk fankly about fuel atomoization differences between carberators and EFI glad to have that discussion.
No matter what you do to a carburator it'll never be anything beyond a gas can with a straw sticking out of it period.
You can add a ton of air bleeding and emulsifiying orifices and circuts you can redesign the discharge orifices all day but its doesn't change that fact ever. A carberator is a pressure differential device. No pressure difference no function. Sure a carb can tolerate low idle vacum becuase the venturi it self genrates Some of the signal. but as soon as that fuel hits the plenum it falls right out of suspension.
we have a huge difference between a Electronics guy and someone who does what he talks about for a living. Honestly the EFI system is not holding the EFI pro-mod back. Something else in the system is.Could be the ratting for flow on the TB's honestly. You have one TB with a rating at 1.5 inchs of mercury and another at 28inch of water deprssion. You also have a laminar flow elemnt in the carberator which is the venturi itself the helps drive airflow through the plate.
but I am done with this topic. EFI wins if carbs are so great why is proof is in the pudding. F1 runs EFI. if a carb had an advatage I think the companies spending millions daily to find HP would be all over it.
If you want to talk fankly about fuel atomoization differences between carberators and EFI glad to have that discussion.
F1=huge technology. No doubt.
Indy car, same thing, or close anyways.
But, you gotta give some props to the NASCAR guys (I'm not a big fan) for gettin it done on 1960s technology. Not to mention all the thousands of bracket cars, circle track cars, that run engines for sometimes several seasons without tear down, and never experience "ring wash" that would be severely detrimental to the performance, and life of the engine.
PS, I also recognize the atomization difference between the two.
We can be done here.
Originally Posted by stevieturbo
But defo cases where vacuum is very low. I can only think, that if you think carbs are easier...you must be trying to tune with a calculator. Because it sure isnt a modern efi system !!
I tune LS1s, LT1s, aftermarket systems, yada, yada. There nothing "easy" about any of them. Not to make a cam with 8 in of idle vacuum drive nice, and idle nice, and return to idle, and not surge.
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Originally Posted by edcmat-l1
I'm sure you can lugg thru a school zone, in second gear, at 25 mph, and 1200 rpms, right?
It won't run at 25 mph and 1200 RPM in 2nd gear (3.42 rear gear) - 1200 RPM 2nd gear is about 14 mph .
It will lope along ....at 1200 rpm in 3rd gear at about 22 mph. Lope ...riding on the cam.
FWIW .
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actually carb are far less forgiving then EFI. EFI systems when properly setup and designed are self compensating.
Sure you can make anything work barely with enough time. If Nascar engine builder could switch to ITB with injector above the plate setups like F! it would happen tommorow.
As for ring wash I ain't gonna waste the time pulling pictures of the many engines I have discetted over the years from the various experts at carb tunning with wasted *** rings and cylinder walls.
What looks good to you might be a totaly failure in my book.
Check the SAE papers on ring and cylinder wear. Look at the average life of a modern engine. in 1980 average engine life was about 70K or so. By 1987 and with the standardization of efi ,engine and seal life doubled. directly attribuable to fuel control.
Sure you can make anything work barely with enough time. If Nascar engine builder could switch to ITB with injector above the plate setups like F! it would happen tommorow.
As for ring wash I ain't gonna waste the time pulling pictures of the many engines I have discetted over the years from the various experts at carb tunning with wasted *** rings and cylinder walls.
What looks good to you might be a totaly failure in my book.
Check the SAE papers on ring and cylinder wear. Look at the average life of a modern engine. in 1980 average engine life was about 70K or so. By 1987 and with the standardization of efi ,engine and seal life doubled. directly attribuable to fuel control.
Originally Posted by edcmat-l1
I do do what I'm talking about for a living. I never said carbs were "better" than fuel injection. I said, and I'll repeat it again for you guys that like to twist words; Carbs are more forgiving than EFI. Listening to the two of you, you would wonder how anything every ran with less than 20 in of idle vacuum before the introduction of EFI.
F1=huge technology. No doubt.
Indy car, same thing, or close anyways.
But, you gotta give some props to the NASCAR guys (I'm not a big fan) for gettin it done on 1960s technology. Not to mention all the thousands of bracket cars, circle track cars, that run engines for sometimes several seasons without tear down, and never experience "ring wash" that would be severely detrimental to the performance, and life of the engine.
PS, I also recognize the atomization difference between the two.
We can be done here.
F1=huge technology. No doubt.
Indy car, same thing, or close anyways.
But, you gotta give some props to the NASCAR guys (I'm not a big fan) for gettin it done on 1960s technology. Not to mention all the thousands of bracket cars, circle track cars, that run engines for sometimes several seasons without tear down, and never experience "ring wash" that would be severely detrimental to the performance, and life of the engine.
PS, I also recognize the atomization difference between the two.
We can be done here.