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Small Block Talk => Small Block Windsors => Topic started by: 82-GT on February 27, 2018, 01:53:09 pm



Title: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on February 27, 2018, 01:53:09 pm
Planning on upgrading to 3/8 line and an electric fuel pump this spring The stock pickup of coarse like the rest of the stock fuel line is about like trying to suck fuel through a catheter so I'll need to go bigger there as well.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: scienceguy on February 27, 2018, 03:03:24 pm
Less ground clearance?   Have to be careful to not back into something?  Mine has been sumped for years.  No problems.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: juiced coupe on February 27, 2018, 03:50:35 pm
Installation is the biggest problem, if you want to call it that.

On a Fox body, oveall ground clearance is about the same. The sump and lines will obviously be hanging in a location where there was previously nothing.

Why 3/8? If you are buying parts, the price difference to 1/2 is negligible.

If you are using any AN hoses and plan on running pump gas, I'd spend a little more and get an E85 rated hose. It'll hold up to the ethanol better.

Even better, PTFE hose. To my knowledge, it would only need replacement if damaged.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on February 28, 2018, 11:56:03 am
No particular reason for 3/8. I just figured the fittings on the fuel pump, filter and regulator were 3/8 and this nothing more than a 300 odd h.p. street car so no reason to go bigger. If there is an advantage to running 1/2" in this application I certainly can.




Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on February 28, 2018, 12:09:50 pm
This is what I have in my cart so far. I know I'm missing something. This is the major stuff. I know I'll need fittings and other odds and ends. Any other major components I need? I can switch the sump and fuel line to 1/2" if there is any advantage on my car.

https://www.summitracing.com/parts/aei-11203

https://www.summitracing.com/parts/aei-13201

https://www.summitracing.com/parts/aei-12308

https://www.summitracing.com/parts/hly-12-810

https://www.summitracing.com/parts/rnb-576-105

https://www.summitracing.com/parts/sum-g2538

https://www.summitracing.com/parts/cee-4040



Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: juiced coupe on February 28, 2018, 12:48:01 pm
The fuel pump is 3/8 NPT, which is a perfect match for 1/2 hard line or -8 hose.


I'd look into a Fox Mustang specific sump. They are a much better fit than the universal ones.


You want a 100 micron filter on the suction of the pump. This is to protect the pump from debris, yet not restrict flow. A restrictive filter on the pump inlet will damage it. Aeromotive has something in their tech area about it.

Even if you use 3/8 lines downstream of the pump, use the larger line on the suction. Same reason as the filter, don't restrict the inlet side. Remember, the inlet side isn't pressurized.


That is a good pump. Just be aware that you can't get replacement parts for it. Once the warranty is out, its a throw away item.


Personally, I'd get the NPT version of the regulator. But I'd be using larger line too. Honestly, a Holley regulator is just as capable and much cheaper.



Before it failed (after a long time), I used to have the same pump on my car. I used a -10 on the suction, with a large screen type filter. I used 1/2 on the outlet, up to Holley 803 regulators. I have 40 micron filters at the carb inlets.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on February 28, 2018, 01:16:10 pm
Thanks. I'll make the changes and search out a sump. Thank you for being patient with all my questions.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: scienceguy on February 28, 2018, 03:06:43 pm
Yea, use 1/2" line.  As was said 3/8 NPT is bigger than 3/8".

A tip for AN fittings...  They go in 1/16th of an inch. 
For example: 
#6 is 6/16"...  which reduces to 3/8"
#8 is 8/16"...  which reduces to 1/2"
#12 is 12/16"...  which reduces to 3/4"

Now, you know...  if you didn't already.  :)


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: juiced coupe on February 28, 2018, 03:14:56 pm
Maybe look into the Mallory 140. Mallory is now owned by MSD, which is owned by Holley. They will sell you nearly any part that you may need for those pumps.

It seems that those pumps have been around forever, and for good reason. They work.

For a little under $400, you get the pump and your choice of regulator. Deadhead or bypass (return).

The return style will require more line and a return line at the top of the tank, but may be better suited to a street car.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on March 01, 2018, 12:37:07 am
Yea, use 1/2" line.  As was said 3/8 NPT is bigger than 3/8".

A tip for AN fittings...  They go in 1/16th of an inch. 
For example: 
#6 is 6/16"...  which reduces to 3/8"
#8 is 8/16"...  which reduces to 1/2"
#12 is 12/16"...  which reduces to 3/4"

Now, you know...  if you didn't already.  :)


Thanks. Never knew this though I feel like I should have. Great information.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on March 01, 2018, 12:43:31 am
Maybe look into the Mallory 140. Mallory is now owned by MSD, which is owned by Holley. They will sell you nearly any part that you may need for those pumps.

It seems that those pumps have been around forever, and for good reason. They work.

For a little under $400, you get the pump and your choice of regulator. Deadhead or bypass (return).

The return style will require more line and a return line at the top of the tank, but may be better suited to a street car.

I'll look into the Mallory pump.. I was originally going to try a Holley Blue pump but a guy at work went through 3 of them in one summer so he switched to the Aeromotive and the problem was solved. His problems kind of turned me away from the Holley Blue fuel pump.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: juiced coupe on March 01, 2018, 03:04:19 am
Don't get me wrong, the Aeromotive is an excellent pump. However, the fact that it isn't serviceable is a disadvantage.

If you still want the Aeromotive pump, there is nothing wrong with that choice. Just know that you can't rebuild it.


The Holley pumps seem to be hit and miss. I've seen some fail in no time, while others seem to last forever. A friend has a set of blue pumps on his street/strip truck that ard around 15 years old. The red pump that I used after the Aeromotive quit was from the mid 90s. Sitting up with fuel (especially pump gas) in them seems to be the cause of many of the fuel pump failures that I've seen.

Regardless of the pump used, having a restrictive inlet line, restrictive inlet filter, or having the pump trying to otherwise suck the fuel are good ways to damage them. The harder the pump has to work, the more likely it is to cavitate.

While hard to do with a sumped factory tank, its best to have the pump near level with the sump. This ensures that the pump gets a good gravity feed.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: scienceguy on March 01, 2018, 09:17:41 am
Maybe look into the Mallory 140. Mallory is now owned by MSD, which is owned by Holley. They will sell you nearly any part that you may need for those pumps.

It seems that those pumps have been around forever, and for good reason. They work.

For a little under $400, you get the pump and your choice of regulator. Deadhead or bypass (return).

The return style will require more line and a return line at the top of the tank, but may be better suited to a street car.

I have Mallory 140's on my car...  one for the engine, one for the nitrous.  They both use the #4309 return style regulators.  The one on the engine has been on there since the fairly early 1990's!  Never a problem with it, and it's seen a LOT of hours and street miles.  It's really old.  It even has replaceable brushes.  The one for the nitrous has been on there since later in the 1990's.  Never a problem with either one.  The return style regulators put less strain on the pumps, and allow them to run cooler, as it's not constantly pumping at full pressure against a 'deadhead' regulator, and the cool fuel is continually cycling through.  They also run quieter.  I HIGHLY recommend a return style regulator.  The Mallory units have been good to me!

Good Luck!


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 289nate on March 01, 2018, 04:56:13 pm
I have also been very happy with my Mallory pump.  I run mine with a return style regulator for the very reasons Mike mentioned.  I've done a rebuild kit on one too.  Not a big deal to rebuild them and yes the kit even comes with knew brushes for the electric motor.

Does anyone happen to have the part number for the E85 safe rebuild kit?  Found at one point then couldn't find the part number later on when I searched.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 289nate on March 01, 2018, 05:01:52 pm
I've found no down side to a sumped tank on the street.  Had a sump welded onto the stock gas tank in my '65 and have never looked back.

E85 safe line was mentioned earlier.  You need an E85 compatible filter element IF you ever plan on running that fuel.  The problem is the E85 can dissolve the glue used on standard elements.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: juiced coupe on March 01, 2018, 05:14:53 pm
You would use the kit for the methanol pump or regulator, depending on which one you are referring to.

I suggested the E85 hose because it holds up better to the ethanol blended gasoline made today. PTFE holds up even better, but requires specific hose ends and costs more.

I have switched all my regulator diaphragms over to GFLT versions to extend service life. As soon as I use up my current supply of carburetor accelerator pump diaphragms, I will be switching them as well (I typically replace them every year).


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 289nate on March 02, 2018, 04:21:34 pm
Thanks for clarifying.  You're not joking about the diaphragms on the accelerator pumps.  Couldn't figure out why my car ran like garbage one day and it turned out the accelerator pump diaphragms were hard as a rock.  Now have the light green ones.  The additional alcohol in today's fuel screws with small carbureted engines (pressure washers and generators in my experience) as well.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on April 28, 2018, 05:23:53 pm
I can't believe how small the stock fuel line is on my 82 GT. It doesn't look like it would feed a stock 4 let alone a v8. If I had realized just how small it was I would have replaced it years ago. Did all year fox bodies come with that small a line? Fuel injected cars must have been bigger.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: juiced coupe on April 28, 2018, 05:45:52 pm
Nope. 5/16".

At 40#, the efi cars can push more fuel through the same size line than a mechanical pump can suck through it.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on June 07, 2018, 12:38:49 pm
Can anyone see any issues that need attention before I button everything up? I know it's probably not ideal but very little I do is, I'm more concerned with will it work and safety issues right now.

(http://i137.photobucket.com/albums/q218/Rumpelhardt/_DSC0012%202_zpsrlqm7wlz.jpg)

(http://i137.photobucket.com/albums/q218/Rumpelhardt/_DSC0013_zpsyaiasrvt.jpg)


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 69 Merc on June 07, 2018, 02:46:54 pm
That top pic's fuel regulator and fittings just above this posting sure are close and above the headers ...    :jawdrop:


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on June 07, 2018, 03:21:08 pm
Closest to the headers is about 2" where the fuel line comes out from under the car. Everything else is 6" or better Do you think that will be a problem? The old fuel line was run through the same spot. I have some header wrap I cam put on it if that would help.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 69 Merc on June 07, 2018, 06:34:11 pm
Posted on: Today at 03:21:08 pm Posted by: 82-GT

"Closest to the headers is about 2" where the fuel line comes out from under the car. Everything else is 6" or better Do you think that will be a problem? The old fuel line was run through the same spot. I have some header wrap I cam put on it if that would help."

It just makes me nervous from the pic directly above the headers because if a fitting got loose it could be disastrous!


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on June 08, 2018, 12:34:44 am
Hmmmm you have a great point. That never dawned on me until you mentioned it. Guess it's back to the drawing board under the hood.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on June 08, 2018, 10:58:53 am
This look a little less nerve wracking? Sure does look less cluttered.  Problem is now I have to order more fittings. I've averaged about one order a week to Summit since I started this little fiasco.

(http://i137.photobucket.com/albums/q218/Rumpelhardt/_DSC0012%203_zpsdisclp7h.jpg)


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on June 08, 2018, 12:29:40 pm
....and yes I know I need to put the fuel line into the side port on the regulator not the end.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: quickshift on June 08, 2018, 08:36:37 pm
I've had no issues.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: quickshift on June 08, 2018, 10:06:10 pm
deleted


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: quickshift on June 08, 2018, 10:19:13 pm
.....newer pic that shows more. Also posted at a different resolution.


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: 82-GT on June 20, 2018, 01:47:53 pm
Got it all together and the highest pressure I can get is 4 lbs. No leaks that I can see. Is this normal or did I screw something up?


Title: Re: What are the major short comings to a sumped stock gas tank on a street car?
Post by: Chickenbone on July 13, 2018, 04:43:40 pm
It may be a little late for this; but I used DEI heat sleeves for the sections of my fuel line leading into the engine compartment.  If you do this, you will need to go 2 sizes larger than your line to accommodate your fittings.  I ran 1/2" line, but had to use 1" heat sleeves to slip over the 8AN fittings.