Fuel Tank Questions

[C10Slim]

So I am thinking about buying one of the CPP aluminum bed mount tank kits. Comes with sending unit and all of that.

http://cgi.ebay.com/ebaymotors/1963-...Q5fAccessories

Have some questions:

• Whats the difference in a 30 and 90ohm sending unit? Which do I need?
• Do you just run the fuel line off the nipple on the sending unit?
• This tank has 2 an type fitting near the bottom of the tank do I use those instead?
• Mechanical pump or do I need an electric?
• What are you guys using for fuel line? Hard lines? Braided hose?

Basically looking for someone to help me design a fuel system that will feed a 383 SB.

Answers/Thoughts/Ideas?

Thanks!

[Captainfab]

What year is your truck? I believe all up thru '66 use the 0-30 ohm sender, I could be wrong though, '66 might be different.

Here's a link that was just posted in 'Racing and High Performance' that talks about fuel systems, and also the thread on this forum.

http://www.centuryperformance.com/fu...e-spg-140.html

http://www.67-72chevytrucks.com/vboa...d.php?t=376000

[lakeroadster]

Whats the difference in a 30 and 90ohm sending unit? Which do I need?

- I assume you have a 60-66 truck. The stock gas gage is made to use a 30 ohm sending unit. If non-stock you need to use whatever sending unit your gage is designed for.

Do you just run the fuel line off the nipple on the sending unit?

- If the sending unit also has has a dip tube that sticks down into the tank to within about 1/4" - 3/8" from the bottom of the tank then that is the line you use for the gas line that runs to your carb. Some tanks have a seperate plate for the gas line fittings, some have everything incorporated into one plate.

This tank has 2 an type fitting near the bottom of the tank do I use those instead?

- If these are just fittings without any internal tubes you don't want to use them for the fuel line that runs to the carb. Pulling the gas out off the bottom means you will also be pulling any dirt and grime into your carb. Not good. These fittings may be return lines for an electric fuel pump.

Mechanical pump or do I need an electric?

For a stock or near stock engine running a carb. a mechanical will work fine. IMHO Keep it simple.

What are you guys using for fuel line? Hard lines? Braided hose

I personally used a 3/8" aluminum hard line from my rear mount tank , running it inside the passenger side frame rail. To connect it to the tank and to the fuel line I used a small length of fuel line.

I hope this helps.

Here is a link to my set-up, Go to post #8: http://67-72chevytrucks.com/vboard/s...d.php?t=363509

[C10Slim]

You guys rock!! Gave me everything I needed. Thanks!

[vin63]

Originally Posted by C10Slim

So I am thinking about buying one of the CPP aluminum bed mount tank kits. Comes with sending unit and all of that.

http://cgi.ebay.com/ebaymotors/1963-...Q5fAccessories

Have some questions:

• Whats the difference in a 30 and 90ohm sending unit? Which do I need?
  The stock gauges are 0-30 ohm and most aftermarket gauges for GM applications work on a 0-90 ohm spec. So, it depends on the gauge you will be using.
  
• Do you just run the fuel line off the nipple on the sending unit?
  For a mechanical fuel pump application, this works fine.
  
• This tank has 2 an type fitting near the bottom of the tank do I use those instead?
  The NPT bungs at the bottom of the tank are generally for electric fuel pump applications - electric fuel pumps are designed to push a column of fuel rather than pull fuel from the tank.
  
• Mechanical pump or do I need an electric?
  This is a personal preference, but if your mechanical pump is working fine, then no need to change. Just plug the bottom bungs in the tank.
  
• What are you guys using for fuel line? Hard lines? Braided hose?
  I use both in many instances - a flex line from the tank and to and from the fuel pump. I use a hardline for the span along the chassis.

Basically looking for someone to help me design a fuel system that will feed a 383 SB.

Answers/Thoughts/Ideas?

Thanks!

Good luck...sounds like a great project.

[C10Slim]

Thanks Vin!


Have one more question eveyone:

Where it the gas tank on a 66 Burb?? I was thinking I could get a pre-bent fuel line for burb and it might get me close enough to the underbed tank mount.

[Oklahoma]

If you are looking for pretty that one looks good for 500$, I got one out of a 79 Blazer for 30$ and it works great. I'm a broke SOB so I use what I can.

[protrash64]

Originally Posted by C10Slim

Thanks Vin!


Have one more question eveyone:

Where it the gas tank on a 66 Burb?? I was thinking I could get a pre-bent fuel line for burb and it might get me close enough to the underbed tank mount.

The gas tank is behind the rear axle on a 'burb. The fuel line runs down the passenger frame rail and stops in that area....a rubber hose attaches the tank to the line. There is also a small rubber 'jumper hose' about 1/2 way down the frame in the middle of the line. I would just buy fuel line and install it...its a straight shot pretty much with the exception of the kick up in front for the suspension/crossmember area.

[51 okie]

I am using the rear fuel tank from LMC. Do I seal the return tube to the tank? Or do I need to put some sort of vented tube on there? It comes with a little rubber cap but I guess the pressure popped it off in the heat of the sun. No bed floor in the truck yet.

[markeb01]

I can’t tell by looking at the LMC catalog page if there is any provision for venting designed into the tank. If there isn’t any, you’ll need to use a vented cap to allow air into the tank to replace the gasoline as it is consumed. If you use a sealed gas cap and that tube is your only vent source, you’ll need to run a line preferably to a fuel filter to keep debris out of the tank. I’m sure the rubber cap was only added as a temporary means to keep dirt out of the tank during shipping, and wasn’t designed as a permanent installation item. Whatever hose is used in the final installation requires some form of mechanical clamp to hold it in place.

[51 okie]

Thanks for your reply Markeb01. When you say "run a line to fuel filter" , I'm thinking a line from that tube on the tank with fuel filter attached at the end acting as an air filter/ vent. Am I correct in that?