My quest for a 9, I failed.

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Yep that's the one I would use. And I agree with "quieter" . My 250 Mallory gerotor is way quieter than my vane Paxton 150, or the trick fuel 140 that replaced it.
Edit: this post may be confusing. The 250 Mallory is on a 9 second small block car, and still works perfectly. The Paxton 150 vane was on a low 11s big block car, but was consistently losing prime, and I got tired of that and replaced it with the trick flow. When the Paxton was primed, it worked just fine.
 
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Thumper built my carb and installed .128” bottom feed needles. His instructions were to run 5 1/2 psi. My current pump is a Holley billet 150, I have a Magnafuel 275 that needs resealed. I resealed it once and it leaked again in short order, may give another try.
You may know this but Magnafuel "warrants" their pumps indefinitely. You can send it back to them, they go through it and replace anything needed then flow test it. All you do is pay for parts. I have an older 275 (maybe 10-15 years old) that quit. Called them, they said send it in, and sent me back essentially a new pump only reusing the housing. Cost less than $70. I was impressed!
 
You may know this but Magnafuel "warrants" their pumps indefinitely. You can send it back to them, they go through it and replace anything needed then flow test it. All you do is pay for parts. I have an older 275 (maybe 10-15 years old) that quit. Called them, they said send it in, and sent me back essentially a new pump only reusing the housing. Cost less than $70. I was impressed!

They didn't mention that when I called. This is the last Magnafuel I'll ever own, apparently the pumps are made here but the motors are sourced overseas.
 
They didn't mention that when I called. This is the last Magnafuel I'll ever own, apparently the pumps are made here but the motors are sourced overseas.
I wouldn't know where their parts are sourced. The pump I have came with my car when I bought it a couple years back. I had sent them an email and got a quick call back from Jeff. I was shocked! Anyhow, they kept me apprised of where my pump was and turned it around in about 2-1/2 week over the Labir Day holidays. If the pump holds up with all these new parts, that kind of service will keep me a customer. The fuel pressure never wavers on mine at the track but your car has considerably more power. (My best is 7.11 in the 1/8th ) FWIW!!
 
I would just flow test the system at the desired pressure and see what it will support.
The system is either up to the task, or it isn’t.
Easy enough to find out.

I have a customer who recently put together a 440 powered street/strip car.
Nothing too serious...... mid-11’s.
He had some sort of Holley 150 thing on it that was absolutely not keeping up.
By the specs, it certainly looked like it should.
If I’m remembering the story right, they had a Holley “Black” 140 on their other car, and they put it on this car for a test.
The problem(motor laying down after 1/2 track) was gone.

Nowadays, when I suspect there might be a fuel delivery issue...... I don’t rely on the specs so much.
I flow the system.

For Justin’s combo, the system should be capable of filling a one gallon can, while maintaining the desired pressure(5.5psi in his case), in just under a minute.
 
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It's got 9s in it. My Dart has always run very close to yours in the 1/8th mile. On Test and Tune day at Drag Week I went 9.95 and it was a 6.338 in the 1/8th. Had to slow mine down a bit to run in the 10.00 class.

What was the DA that day? I've always wanted to go to Moparty but It's always when we are driving back from Dragweek.

Dart 7.jpg
 
I don’t honestly feel the fuel system was holding me back. Is it marginal for 1/4 mile racing? Yes. But holding me back? No. It pulls like a freight train all the way through.

I’m not really disappointed. IMHO, any pump gas small block running 10 flat at 3300# is pretty cool, mine or not. It’ll hurt a lot of big block guys feelings. :lol:
 
Curiosity, what am I seeing there for a fan? is it attached to the water pump, not clear in the pic.
 
I use a Holley Black pump on my 408 with e85 and it works just fine, runs low 10's with an AFR of 0.78 lambda.....and it is flowing ~30% more fuel than you pump gas folks (i.e. the Black pump can support that no problem).
 
I would just flow test the system at the desired pressure and see what it will support.
The system is either up to the task, or it isn’t.
Easy enough to find out.

I have a customer who recently put together a 440 powered street/strip car.
Nothing too serious...... mid-11’s.
He had some sort of Holley 150 thing on it that was absolutely not keeping up.
By the specs, it certainly looked like it should.
If I’m remembering the story right, they had a Holley “Black” 140 on their other car, and they put it on this car for a test.
The problem(motor laying down after 1/2 track) was gone.

Nowadays, when I suspect there might be a fuel delivery issue...... I don’t rely on the specs so much.
I flow the system.

For Justin’s combo, the system should be capable of filling a one gallon can, while maintaining the desired pressure(5.5psi in his case), in just under a minute.
 
Electric water pump and fan combo has picked up right at a tenth on 4 or 5 different combo’s my brother and i have made that change to.
 
Electric water pump and fan combo has picked up right at a tenth on 4 or 5 different combo’s my brother and i have made that change to.
This is why I asked. Shy of skipping the chili cheese dog and fries, ditching the fan set-up could net some gains.
 
I would just flow test the system at the desired pressure and see what it will support.
The system is either up to the task, or it isn’t.
Easy enough to find out.

I have a customer who recently put together a 440 powered street/strip car.
Nothing too serious...... mid-11’s.
He had some sort of Holley 150 thing on it that was absolutely not keeping up.
By the specs, it certainly looked like it should.
If I’m remembering the story right, they had a Holley “Black” 140 on their other car, and they put it on this car for a test.
The problem(motor laying down after 1/2 track) was gone.

Nowadays, when I suspect there might be a fuel delivery issue...... I don’t rely on the specs so much.
I flow the system.

For Justin’s combo, the system should be capable of filling a one gallon can, while maintaining the desired pressure(5.5psi in his case), in just under a minute.
How do you recommend that test be done? Metered orifice in the fuel line, or both float bowls in a bucket, or......? If a metered orifice, how do you determine size? Calculated from n&s size?
 
This is how i did it
remove fuel line from carburetor. I have two lines coming off the regulator going to the front and rear bowls. needle and seat keep one bowl with 0 flow and the other you do your test with.

now you need to add to that line a fuel pressure gauge(not in line) a shut off valve and several bucket. Gas can with Gal increments on the side.
With hose from your new line with the gauge and the valve into a bucket. any bucket will do.
Now turn on your pump (this only works with electric fuel pumps that can be activated with out the eng running) Close down shut off valve until your pressure comes up to.5.5 psi in this case.

when you have a stable fuel flowing at 5.5 psi. You move it to a measuring container and start your stop watch. when a minute has past you close the shut of valve completely and read how much fuel you got in one minute.
I when 2 minutes and then divided by 2 to get a better average of how much fuel you got in a minute.
 
Fuel delivery issues "at the top end", I'd be making sure the tank can vent properly and isn't creating a vacuum, filler cap problem?
 
I had to put my backup motor in a few weeks ago and have been trying to get in the 9's.
I finally did.
But it's been a pretty good 10.0 index motor if I ran that class...

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I had to put my backup motor in a few weeks ago and have been trying to get in the 9's.
I finally did.
But it's been a pretty good 10.0 index motor if I ran that class...

Congrats on your 9! What power plant and weight are you running?
 
How do you recommend that test be done?

I run a hose off the regulator to a can.
Ball valve in the end of the line, gauge in the line right before the ball valve.

With the pump running set the ball valve to where the gauge reads the desired minimum pressure you’d be happy seeing down track.
Shut off the pump(don’t change valve setting).
Get your one gallon can ready........ turn on pump and time how long it takes to fill the can while maintaining the minimum desired pressure.
Figure out the gallons/hr of flow you have and compare to the engine requirements.
 
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