I tried this once, and the thread got tagged onto the end of my earlier post. I am adding a surge tank between the fuel tank, and the high pressure fuel pump, which I plan on feeding with the stock mechanical pump. Does any body know the volume, or flow rate of the stock pump? The surge tank is about a 1 and 1/2 quart. How long can I run the turbo at WOT before I drain the fuel from the surge tank.? In other words, is there a chance in hell the volume of the stock pump can keep up with a turbo slant with 30 lb injectors? If not, what is the difference in the flow rate of the mechanical pump and the demand of the injectors?

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69 Dart Swinger, 230 ci slant, t-5 five speed, intercooled turbo, 4 wheel disk brakes, tubular upper control arms.

I would rate a stock fuel pump's flow at 50-60 gph. (gallons per hour)
Who knows if that will be enough to keep the surge tank supplied.
One option I have used is to buy a high volume pump for a BB Mopar and switch the activating arm with one off a SL6 pump. The Carter HV pump flows 120 gph.
DD

http://www.dutra.org/pictures/engine/fuel-pump.jpg

Thanks for the tip Doc! I am sitting here trying to figure if this will work the way I have set it up. I have not fired it up yet. The concern is that the electric pump is not entirely below the level of the fuel in the surge tank. I am afraid it might not pick up a prime. Has anybody out there mounted an electric pump about half way down the level of the fuel tank, and still had it work, or am I trying to do something impossible here? The electric pump is where it is for a lot of complicated reasons.

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69 Dart Swinger, 230 ci slant, t-5 five speed, intercooled turbo, 4 wheel disk brakes, tubular upper control arms.

I would say unless you are on a racetrack and running WOT for several minutes, you will not have a problem with the stock pump.

Your motor, with injectors maxed out, will consume about 160-180 lbs/hr or 3lb/min. Your tank will hold about 1.5lbs. Doubt you'll be at WOT and max RPM for more than 30 sec at a time...

Lou

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Home of Slant6-powered fun machines since 1988

My surge tank is about 1 liter and my injectors are 36#'s. I've never run dry with the stock mechanical pump keeping it topped.

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Cheers!
Al T

BTW, my 68 Dart is now up and running with MS/MP-EFI. Smooth as silk and still tuning up.

Yep, that fuel pump is loud...

Lou

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Home of Slant6-powered fun machines since 1988

The fuel pump does seem to work as I have it mounted. Under the hood, I can't hear the pump anymore. There are still a few bugs to be gotten out. One of my sensors must not be giving reliable info to the ECU, as she still exhibits a sudden and annoying change in AF ratio every once in awhile. You might have noticed my other post about the ignition switch. I have a spare, but no key for it. I could go to a locksmith, but he would charge as much as a new switch, and then I still have an old switch. Lou, your formula for the availability of fuel, and how long it would last sounds reassuring, especially if you figure the mechanical pump is always refilling the tank. It should last way longer than 30 secs. And you are right, even if I were to road race it, which is not likely to happen, there would few times I would leave the pedal to the metal that long. Congrats on your '68 being up and running!

Does anybody know how "three deuce webber" got under my name? It is not true of my car, and I don;t know what made it appear.

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69 Dart Swinger, 230 ci slant, t-5 five speed, intercooled turbo, 4 wheel disk brakes, tubular upper control arms.

"3 duce webber" means you have over 50 posts.
Keep posting and someday you will get to "EFI"
DD