Are my expectations too high?

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What carb is on it? The reason I ask is I'm dealing with the same issue right now (stumble at the hit of the throttle) with my 950 XP carb. After a lot of tuning the right way (shooters, cams, mixture screws, etc), my guess is it has something to do with the controlled air-bleed feature (I don't recall the correct name for that thing) near the carb stud...or at least that is where I am looking next. I have a friend at the track that fought the same issues with an XP carb, and the only way he found to fix it was to close the "air-bleed thingy" and adjust the idle the old fashioned way.
 
What carb is on it? The reason I ask is I'm dealing with the same issue right now (stumble at the hit of the throttle) with my 950 XP carb. After a lot of tuning the right way (shooters, cams, mixture screws, etc), my guess is it has something to do with the controlled air-bleed feature (I don't recall the correct name for that thing) near the carb stud...or at least that is where I am looking next. I have a friend at the track that fought the same issues with an XP carb, and the only way he found to fix it was to close the "air-bleed thingy" and adjust the idle the old fashioned way.
It is a Holley 4779 750 DP. That’s weird because I have noticed a weird vacuum noise intermittent but cannot find a vacuum leak anywhere
 
It is a Holley 4779 750 DP. That’s weird because I have noticed a weird vacuum noise intermittent but cannot find a vacuum leak anywhere
Gotcha. That style does not have the "feature" that I'm talking about. Mine is more than likely a momentary lean stumble...which I should be able to cure, one way or another. Pump cams and shooters are usually the way to cure it.
 
Gotcha. That style does not have the "feature" that I'm talking about. Mine is more than likely a momentary lean stumble...which I should be able to cure, one way or another. Pump cams and shooters are usually the way to cure it.
It has out of the box squirters in it. I was thinking of stepping them up
 
What carb is on it? The reason I ask is I'm dealing with the same issue right now (stumble at the hit of the throttle) with my 950 XP carb. After a lot of tuning the right way (shooters, cams, mixture screws, etc), my guess is it has something to do with the controlled air-bleed feature (I don't recall the correct name for that thing) near the carb stud...or at least that is where I am looking next. I have a friend at the track that fought the same issues with an XP carb, and the only way he found to fix it was to close the "air-bleed thingy" and adjust the idle the old fashioned way.
Hey flyfish I tried to send you a PM but your inbox is full
 
Update: first time out on a hot August day the car went 12.94 @ 104.19 and the slowest time was a 13.003 @ 103.79 BUT I know there is a lot more in it. The car has a horrible stumble in it off the line that I need to work out and it needs jetted up. The plugs are on the lean side. I was very pleased on how consistent that the car is running within.006 of a second of itself with over 12 passes over a 3 day period at the Mopar Nats.

UPDATE: I found out why the engine was running lean and the stumble. Also the number 8 cylinder was getting oil in it. The intake was leaking causing the lean condition and also pulling oil into the #8 intake port. I also found out that I had WAAAAY too much timing in the motor. Not sure if both of these problems was a result of me thrashing hard to try and get this thing ready for the event or what but I re-sealed the intake and set the timing properly. This thing feels really good now. Waiting for the next opportunity to take this thing back out to the track.
 
UPDATE: I found out why the engine was running lean and the stumble. Also the number 8 cylinder was getting oil in it. The intake was leaking causing the lean condition and also pulling oil into the #8 intake port. I also found out that I had WAAAAY too much timing in the motor. Not sure if both of these problems was a result of me thrashing hard to try and get this thing ready for the event or what but I re-sealed the intake and set the timing properly. This thing feels really good now. Waiting for the next opportunity to take this thing back out to the track.
our Mag did the same thing on all 8 cyl due to mismatched intake ports on a ChiCom intake.
Took a min to figure out!!
 
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