Well just got back from the track, and let me tell ya I should have staied home.First off I had to stop three times on the way out there, cause my trailer lights went out.. So I can deal with that, I got them fixed and on our way. Get to the track and un-load the car and take it to warm up. Right of the car just didn't sound right.. it starts to stall, now what.. Well dumby me forgot to take the cab hat off.. Well that wouldn't be the last time for that.. I ended up doing it three times total. Okay so I take the car up and do the burn out, all is right with the world, stage the car and bam I slap the gas, the car just blows the tired off.. then went hard to the left, what the heck is that.. so I'm out of the gas right after second gear.Come back check the tire pressure, its at 20lbs not good.. So I drop the pressure, take the car back up.. Stage it leave, okay that felt better, pull second its still pulling hard, pull third and thats when it all starts, the car starts bucking, falling on its face and then picking up again.. I look at the fuel pressure and its at 2.5 and bouncing to 3.0 and back, so I get out of the gas at the 1000ft marker and runs 10.17 at 132.963 So I think the prerssure is to low.. Soooooo I raise it up to 7, I had it set at 6 the runs before.. Go back up and the same thing happens.. third gear falls om its face, 2.5, 3 pounds, so I back out of it again at little past the 1000 ft runs 10.02 134.623 What the crap is going on.. Come back jack the pressure up to 7.5 pounds, go back up for the same thing.. Third gear 2.5, 3 pounds, runs 10.02 130.236.. Man I'm done, so I load it up and come home. Sooo whats the deal???  I got no idea, the only thing I did was replace the holley blue pump with the new Mallory 140 plus regulator.. I don't understand what the problem is.. I'm bout ready to pull the pump off and throw it as far as I can, and put my crappy blue pump back on. Go with a better pump and go slower, went 9.80 with the crappy blue pump..  Any ideas.. Let them fly..

What prompted the changes you made?

Are ya running a braided rubber "non colapsable line. My buddys dirt car did that after a fresh pump swap, they have to run mechanicle, but anyhow, the pump sucked way better and the fuel line on the inside would pull together, and pinch off the fuel. If you have aluminum line, I have no idea..

Kasey

Now that does sound like a crappy night.

Any thing restricting the flow on the new lines? Can you disconnect the lines and have it pump into a jug to see that it remains steady for 30 or so seconds.

Might be worth swapping the pumps at the track if its not too much work. I dont have any experience with the mallory pumps. But know the blue has been and was the staple for many many years.

Could be a filter.... time to do the gallons per
minute test(flow rate)

I just been kicking around the pump change. I talk to some people, even a post on here, and most everyone thought I was at the usefully end of the holley pump.. Kasey, Its all braided line from the front to the back..  

What is between the pump and the tank? A freind of mine recently upgraded his fuel system and had a similsr problem, the new pump would suck the fuel filters dry which ended up driving the fuel pressure down at the carbs. His old system was two Holley blues(one started leaking) with two Fram chrome canister fuel filters between the fuel cell and the pumps, out of the pumps into a Y (all # 8 lines between the Y and the fuel cell) and then a # 8 to the front with two little Holley fuel regulators, one for each carb. He replaced the pump with a BG 480 and athe little Holley regulators with a four port Aeromotive return style regulator with a #10 feed from the back and a # 10 return to the cell The only thing he left was the two Fram fuel filters fed by 2 # 8 lines into the Y and then into the BG 480 He now has two inline 40 Micron Aeromotive fuel fliters that are rated to flow a lot more than the two Frams that where rated at 90 GPH or less

Codys late models line that would flap shut happened right where is came around the tube bars from the cell, it was only 3 years old, but it was definatly the problem. We dicected the line basically like a fish, and fount that. Just an Idea...
Mr P ight be onto something with the filter, or fuel log...

Kasey

First thing I thought of while reading your post was ,did he forget to put the fuel in? Maybe you have a pinched line? crap in the filter. The new pump seems to be building pressure while the motor isn't using it but can't keep up at high rpm.I would put the old blue back on to see if it is the new pump.

Nope It had fuel in it, I even put more in it.. I am running a fram filter. I was thinks that might be it. But any how its got two -8 off the tank to a Y then to the fram fiter, to the pump with -8 and to the front of the car with -8 to the regulator, and two -8s to the carb..

What do ya mean MR P Body.. How do I check that??

Its just like doing a volume check with a diesel, Get a graduated can, mark it off in say 3" incruments, and time how ling it takes to reach a certain line, do the calculation and you have it.

In a new EFI dodge it is day half a liter in 20 seconds I think, something like that, I dont have the chart in front of me.

Kasey

Hows the voltage to the pump? are you using an altenator? if not your ignition could be drawing most of the current and leaving the pump low on amperage as the rpms increase so does the demand for more current for the ignition and the pump. Maybe you new pump demands more current than the holley did. Just somthing to think about.

First of all, it wasn't THAT bad; you didn't wad it up or blow it up!

I had the EXACT same problem once. Reset psi, changed regulators twice, changed pump relay, pump switch, re-wired pump/relay wiring, changed carbs twice, changed pumps THREE times...same problem. Changed brands of fuel THREE times, no solution. Pump test? Each time and each pump passed with flying colors? I'm pullin' what's left of my hair out...GRRRRRRRRRRRR. Wife says, you've changed everything but the fuel cell, might as well try that. I do it, all the while thinking she's nuts, but what the heck...

New cell: Problem solved. Turns out the foam was breaking apart and upon acceleration a chunk was covering the sump!! Who woulda thunk THAT??!!??

Cover ALL of the basics first, don't ASSume all components are working correctly...check everything!!

Good luck and let us know what happened.

I checked the voltage, its Okay. It has a charging system on it. I'm going to check the flow rate here in a bit. It still has the stock tank on it, with a sump. I'm trying to not over look anything though, I will find the problem..

FWIW, I was running the mallory 140 in the coronet with the old motor making 550 hp or so.
With the new motor doing 770 on the dyno, Brian was concerned that the 140 wouldn't be enough pump.

I called RobbMC (before opening his business he was a design engineer at mallory) and he confirmed the 140 would be marginal at best at my new power level.
Mallory lists it as for 600 hp max (600-700 with a return style regulator), and he said they do build a safety factor into their published numbers.

They list the 250 as the recommended pump for 700-1200 hp applications.
So, the car now has a mallory 250 in it.

Based on your et's, you're makng around the same or better hp than I am, so I'm going to say the 140 just isn't enough pump.

Okay Bob, I thought the same thing but the old bule was carring that thing to 9.80s.. Time and again.. So I talk to a rep at mallory and he siad that it should be fine for it..

I also did a flow check, took the line off the regulator and checked it, it filled a gallon in 29.32 seconds. So I took the fram filter out of the canister and checked it again, it flowed a gallon in 23.25 seconds.. The pump was changing the out put from hard to light with the fram filter in it, then when it was off it didn't change at all.. What do you think..