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Discussion Starter · #1 ·
I have a 69 fastback with a fresh 393 stroker with the Edelbrock RPM package. While driving it on the freeway last fall, it seems I am running the bowls dry when running down the freeway for a length of time. When pulling off the road, the bowls of course catch up and the car starts running again.

I rpelaced the filter, which had some resistence, but not bad, and put away the car for the winter. As spring is just around the corner, I think it is time for a fuel system upgrade. First thing to note; when getting all my parts for the complete build, I went with a stock pump, and the stock pump looks like it was for a 302 rather than a 351. The diaphragm was smaller that the previous 351 pump I had in there, and it matched the 302 pump in my Maverick. That could be problem number one.

In upgrading, I have read that engines making over 400 HP heed a larger diameter fuel line than the 5/16ths from the factory. The problem is that the system can only flow as well as it's smallest restriction, and the outlet from the fuel gauge assembly in the tank has a 5/16th outlet that would be tough to change without some custom welding.

I would like to stick "bolt-on", and I would like to stick mechanical, if possible.

What are you guys with similar applications using in your set-ups?

(see, it only took me 500 words to ask a simple question!)
 

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bolt on, get the fuel pickup for a 69 Boss 302, 428 SCJ/CJ or Boss 429 gas tank, then just run they're larger fuel line. Also use a Boss 302 fuel pump or Holley mech fuel pump. Cost you more for the HiPo parts but it'll look stock that way and have the larger lines and pump.. 5/16 in way to small for anything more then a stock 302 2V
 

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On my 65' I also wanted to upgrade my fuel system. 3/8" fuel lines are availabe pre-bent from most Mustang parts places.

When it came to the fuel sensor, I was pleasantly surprised that aftermarket replacements were built using 3/8" lines. I checked with my supplier and he verified it before I ordered. I'm sure it will be just as easy to get one for your 69' too since larger engines were common.

I bought an Edelbrock street mechanical fuel pump that had 3/8" inlets and outlets. It give a solid 7 lbs of pressure to the carb--I believe it is rated at 110 gph.

_________________
Dennis

65' Stang

393 stroker, Toploader 4 spd, 3:50 rear.

Victor Jr. knockoff heads, 282S cam, Stealth intake, Bigs Stage 5 750DP, Accufab headers, Scattershield, Caltracs.



<font size=-1>[ This Message was edited by: dennis111 on 2/26/06 7:50am ]</font>
 

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Discussion Starter · #5 ·
Good info. Thanks! I had no idea they used larger diameter lines for the Bosses.

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77 Maverick
69 Mustang Fastback 393



<font size=-1>[ This Message was edited by: MaxPower on 2/27/06 5:10am ]</font>
 

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I think if you're running the bowls dry at highway speeds you've got other problems. The motor isn't making anywhere near full power cruising down the road, it only takes a small amount of power to push a car at highway speeds. Not sure exactly, but well under 100 HP. Even with 5/16" lines you shouldn't have any problem keeping the bowls full. I owuld check the pressure at the carb with a gauge first, your pump may be defective. Also I would pull the pickup out and make sure it's clean. If it's never been out, it's sure to be dirty. Or you could just upgrade everything anyway!
 

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cruising shouldnt drain the car on 5/16 lines. my reolacement mustang tank came with a 3/8 pickup.
 

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I would suspect trash in the tank is blocking the pickup tube.
 
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