Finally got the car to the track for the first time tonight. 528 hemi challenger, 10.3 compression, 630/618 lift, 295 duration, iron heads with some mild clean up work, factory intake opened up, 2 original hemi afb's, 2 1/8 headers, 3.5 collectors to about 18" of pipe to 3.5" aero chambers, 727 ,foot brake, 3500 converter, 4.30 geared dana, 29" tire. I made 3 passes tonight with it. It's 60 foot was 1.607, which I'm fine with since I was only leaving at about 2800rpm. I wanted to get a feel for the car a bit before I leave harder. It pulls well up to about the 1/8th and falls on its face at about the 1000 foot. I'm in 3rd before the 1/8. 1st and 2nd pull strong to about 6500 where I was shifting at. It doesn't break up or miss or anything, it just falls flat on it's face and stops pulling. My plugs look really good. Where do I start? I'm at a loss here. 7.4 at 92mph 1/8 and 11.95 at 96 mph was my best 1/4 of the 3 passes.

Sounds like its running out of fuel. What kind of fuel system do you have?

Holley blue pump with 1/2 inch (8an) line to a high flow filter, I forget the make, to a regulator under the hood that splits with 2, 3/8 lines (6an) lines, 1 going to each carb.

The fuel cell "output" fitting is 8 or 10an, I'm not sure, but the line at the cell is definately an 8 (1/2 inch).

Where is the filter in relation to the pump and tank? I had problems with using a B.G. 500 fuel filter with a 10 micron paper elemnet restricting the fuel to the pump from the tank Have you flow tested your system at all? If so how long does it take to fill a one gallon container? If not try that and let us know how long it takes, flow it through both lines into one container if you can

The pump is about 12" from the fuel cell, and below it. Cell in the trunk, pump under the trunk. The filter is on the subframe connector. The filter is pretty big and made to go after the pump and although I don't remember the make of it, I do remember the flow rate on it was really high. I have not flow tested the system. Guess I know what I'll be doing tomorrow morning. Any numbers I should be shooting for? Less than so many gallons per minute is bad? I ask because our local speed shop closes at noon so if I'm buying a pump, I have to get it figured out by then. I want to get back to the track Sunday!!

Two things that come to mind are:
1. Are you getting full throttle (butterflies opening completely)?
2. What size needle and seats are you using ? Too small could be restricting fuel into the bowls.

What was the rpm in 3rd at 1000 ft ?

no mention of fuel pressure ????

3 things come to mind, flow test it, fuel pressure,
and those carbs only have a single inlet and bowl and
they do have a tendency to empty the bowl at high revs

You need more info:
1. Fuel PSI at the carbs downtrack
2. What jetting & etc (i.e. stock 426?)
3. Any restrictions in fittings, etc (some really neck down)
4. Do plugs look lean, really clean?
5. RPM @ 1000ft/3rd gear

check fuel pressure
have 7 1/2 # and only slight drop off at w o t
may think about alittle better pump for the hp you have going and the amout of draw on the fuel system,
also just for giggles, check your vent , do not want a restriction there as well,

Another thing, you say the plugs look good, but it's falling on it's face at 1,000'. When are you checking the plugs? I'd shut it off when it falls off and tow it back and check them.

Well thanks all for all the input! The needle and seat are the largest available for an AFB. I had bought all good fittings that don't neck down. I'll be checking the flow and for trash in the lines and vent, and everything else everyone said. RPM when it falls off is about 4000. 1st and 2nd shifts are around 6500 and its still pulling strong.... good point on the plugs. I'm pulling them after I get back to the pits. I'll look over everything today and get back on here with my findings. Hopefully the weather holds out for tomorrow. 60% chance of rain,,,, but better than

If you can fill a one gallon container in under 30 seconds you should be good for a 11 second car, BG use to have a flow chart on thier website saying that a nine second car needed one gallon in or under 20 seconds, 10 second was, maybe, 25 seconds My memory is horrible, maybe someone else on here knows of another site that has flow numbers for testing and will post a link or say where to go to The comment on the needles and seats is very apprpriate, I have gone through that on many carbs, a .110 needle and seat would starve the motor according the wide ban and a .120 was more than enough Good luck, fix it before you burn the motor up In other words lift if it noses over

If it falls down at the 1/8 let off completely then get back in if it pulls strong it was low on fuel in the carbs.

1 gallon in 45 seconds from the blue pump. Picked up a Holley 150 black pump today. It's flow rate is pretty good, came with a new regulator, and it's alcohol compatible if I ever decide to change over. Looking like rain for tomorrow so hopefully if it's dry Wednesday night I'll bring it up to Island for a few passes. http://www.holley.com/12-150.asp

Cab, I think you're about right on the secs/gal; I seem to recall that 20 secs/gal is good for a low-10-sec car.
Fig, take a really good look at your spark plugs & check your float settings, and if there's any rubber hose in the system, make sure there aren't any internal cuts that can create a flap inside the hose that reduces the amount of fuel it can flow. If you're running a stock pickup, make sure the fuel isn't pulling away from it; on my Roadrunner, I added a length of suitable hose that lays on the bottom and extends rearward a bit inside the tank. My Duster uses a sump.