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Sure I have.Keep using it to make changes and you keep slowing down.It cant predict track or air .So once again carbs will compensate for small changes.Every round guys dicking around with laptop.Carbs we are not !
Its scary that someone may actually listen to the things you post
 

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Maybe you should hit mike up,Our shit runs what the dyno says!!Maybe he can save yours!
I set a goal, and I've met it. I'm proud of where I am with the car on my budget. My pockets aren't deep enough to run a faster car on a regular basis. Thank you for your positive words of encouragement.

I've worked alongside Mike on a car much faster than mine. He has already made suggestions concerning my car, and said that when I'm ready to bolt on perfection, let him know, he can give me a hand.
 

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We have bought and used multiple systems had supposed some of best gurus in efi work on them,we have have dynoed multiple deals and learned them ourselfs.Still back to carbs every time!!!
I'd still like to hear how a carb can adjust itself for conditions? I think the point you are missing is that carbs can be dialed in on a dyno but that means you better be racing in those exact same conditions or your tune will be off, It might be slightly off or it might be way off either way it won't be making the same power it was on the dyno and as close as EFI is to a carb on the dyno it has the potential to make more power than the carb at the track unless you can tune the carb just as well as it was when it was on the dyno and most people can't/don't/or won't bother.
 

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It cant predict track or air .
Last I knew a carb couldn't predict the track either, EFI doesn't predict because it doesn't need to, It actively monitors fuel ratio and adjusts as needed and it does it faster than the ratio can get out of wack. There is a video on youtube that shows the tuner take half the fuel away from the fuel table and then do a full dyno pull and the ratio was still perfect because the Holley added more fuel where it was needed.
 

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Last I knew a carb couldn't predict the track either, EFI doesn't predict because it doesn't need to, It actively monitors fuel ratio and adjusts as needed and it does it faster than the ratio can get out of wack. There is a video on youtube that shows the tuner take half the fuel away from the fuel table and then do a full dyno pull and the ratio was still perfect because the Holley added more fuel where it was needed.
One pass on my FT550 and the next pass the AFR was spot on the whole pass.
 

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There is some misinformation going on here, a carb does "self adjust" to a degree. It delivers fuel based on a pressure differential between atmosphere (bowl pressure), and pressure inside the booster. As the Baro changes these pressures will change as well. If I remember correctly Jay from Hendrick said in his experience their carbs would not need to be rejetted unless the DA swing was more then 800 ft. I would say most bracket racers are not rejetting their carbs if the DA swings 500-600 foot and they still run right on the number. The difficult thing with a carb is setting it up to deliver the proper amount of fuel under varying air speed / load values.

EFI just does what you tell it to do. Closed loop is reacting to a combustion event that already occured in order to adjust for a predicted future event. If you completely rely on the closed loop to adjust it will always be trying to play catch up and sometimes those swings can vary. This is why its important to adjust the main fuel table based off the closed loop correction to stay closer to your target. The benefit is typically it only takes 3 or 4 passes to do this. Depending on the EFI system you are using you can have tables setup to adjust the main table for each gear, cylinder, air temp, and even DA.

When both are setup correctly, manifold pressure is similar, and both deliver the proper amount of fuel for the given rpm/load, the power numbers are extremely close.

This is just my opinion from what I have personally learned working on higher rpm carb and efi engines
 

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There is some misinformation going on here, a carb does "self adjust" to a degree. It delivers fuel based on a pressure differential between atmosphere (bowl pressure), and pressure inside the booster. As the Baro changes these pressures will change as well. If I remember correctly Jay from Hendrick said in his experience their carbs would not need to be rejetted unless the DA swing was more then 800 ft. I would say most bracket racers are not rejetting their carbs if the DA swings 500-600 foot and they still run right on the number. The difficult thing with a carb is setting it up to deliver the proper amount of fuel under varying air speed / load values.

EFI just does what you tell it to do. Closed loop is reacting to a combustion event that already occured in order to adjust for a predicted future event. If you completely rely on the closed loop to adjust it will always be trying to play catch up and sometimes those swings can vary. This is why its important to adjust the main fuel table based off the closed loop correction to stay closer to your target. The benefit is typically it only takes 3 or 4 passes to do this. Depending on the EFI system you are using you can have tables setup to adjust the main table for each gear, cylinder, air temp, and even DA.

When both are setup correctly, manifold pressure is similar, and both deliver the proper amount of fuel for the given rpm/load, the power numbers are extremely close.

This is just my opinion from what I have personally learned working on higher rpm carb and efi engines
Nice,logical info
 
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That's Common sense 4 you, with the Rules of a 4 stroke combustible engine.
Pro Stock or Nascar proved it...
#6 on the list showed us with EFI University.
 

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EFI can be used with fuel delivery just like a carb with computer monitoring to react due to different conditions, quicker than.
Technology I tell you

Colorado said it.
Common sense on Mimicking what's known as King with technology.. carb is good 👍 but....
 
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There is some misinformation going on here, a carb does "self adjust" to a degree. It delivers fuel based on a pressure differential between atmosphere (bowl pressure), and pressure inside the booster. As the Baro changes these pressures will change as well. If I remember correctly Jay from Hendrick said in his experience their carbs would not need to be rejetted unless the DA swing was more then 800 ft. I would say most bracket racers are not rejetting their carbs if the DA swings 500-600 foot and they still run right on the number. The difficult thing with a carb is setting it up to deliver the proper amount of fuel under varying air speed / load values.

EFI just does what you tell it to do. Closed loop is reacting to a combustion event that already occured in order to adjust for a predicted future event. If you completely rely on the closed loop to adjust it will always be trying to play catch up and sometimes those swings can vary. This is why its important to adjust the main fuel table based off the closed loop correction to stay closer to your target. The benefit is typically it only takes 3 or 4 passes to do this. Depending on the EFI system you are using you can have tables setup to adjust the main table for each gear, cylinder, air temp, and even DA.

When both are setup correctly, manifold pressure is similar, and both deliver the proper amount of fuel for the given rpm/load, the power numbers are extremely close.

This is just my opinion from what I have personally learned working on higher rpm carb and efi engines
Thank you.
I call carbs "infinitely intelligent".
 

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I would say most bracket racers are not re-jetting their carbs if the DA swings 500-600 foot and they still run right on the number.
You are correct that many racers don't need to swap jets on small DA swings. The carb will compensate for a proper air-fuel ratio if tuned correctly. An experienced bracket racer will adjust his dial-in based on atmospheric conditions. DA has less of an effect on vehicles running superchargers, turbos, or nitrous.

For example, my car is naturally aspirated. First two time trial runs, early in the day, I ran a 10.06 and 10.07. By second round, DA was on the upswing. I dialed-in a 10.13 and ran a 10.122.
 

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There is some misinformation going on here, a carb does "self adjust" to a degree. It delivers fuel based on a pressure differential between atmosphere (bowl pressure), and pressure inside the booster. As the Baro changes these pressures will change as well. If I remember correctly Jay from Hendrick said in his experience their carbs would not need to be rejetted unless the DA swing was more then 800 ft. I would say most bracket racers are not rejetting their carbs if the DA swings 500-600 foot and they still run right on the number. The difficult thing with a carb is setting it up to deliver the proper amount of fuel under varying air speed / load values.

EFI just does what you tell it to do. Closed loop is reacting to a combustion event that already occured in order to adjust for a predicted future event. If you completely rely on the closed loop to adjust it will always be trying to play catch up and sometimes those swings can vary. This is why its important to adjust the main fuel table based off the closed loop correction to stay closer to your target. The benefit is typically it only takes 3 or 4 passes to do this. Depending on the EFI system you are using you can have tables setup to adjust the main table for each gear, cylinder, air temp, and even DA.

When both are setup correctly, manifold pressure is similar, and both deliver the proper amount of fuel for the given rpm/load, the power numbers are extremely close.

This is just my opinion from what I have personally learned working on higher rpm carb and efi engines
Good post.

I'll add a vote for the carb side. All else aside, I like the lack of wiring and the simplicity of a carb.
 

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What is this "dial in" you speak of? 🤪
 

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So with EFI what would be the spread between good air and bad? My home built carbs are usually less than .15 from best to worst air, would efi narrow that? That's probably a 3000ft change in da, I never jet for bad air.
 

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So with EFI what would be the spread between good air and bad? My home built carbs are usually less than .15 from best to worst air, would efi narrow that? That's probably a 3000ft change in da, I never jet for bad air.
Lots of variables there. Closed loop vs open loop.But my bracket bike running a Motec in closed loop varied about the same as yours.It ran high 5.0s at sea level and a worse of low 5.20s at almost 4000ft
 

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So with EFI what would be the spread between good air and bad? My home built carbs are usually less than .15 from best to worst air, would efi narrow that? That's probably a 3000ft change in da, I never jet for bad air.
Lots of variables there. Closed loop vs open loop.But my bracket bike running a Motec in closed loop varied about the same as yours.It ran high 5.0s at sea level and a worse of low 5.20s at almost 4000ft
We see right around the same, roughly .10-.12 and 2 mph from a 2500-3k foot swing, Carb or EFI
 
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