My '68 Cutlass S really sat for a number of years before I bought it and really needs a new gas tank. The old tank is rusty, and I am seeing a lot of crud in the fuel filter,

I currently only have one fuel line (no return), and I am running a carb. At some point I am thinking of converting to a Holley Sniper or if I can afford it one of cutlassefi's multi-port fuel injection systems, but for the foreseeable future, I was planning to keep the mechanical pump and carb. I know that Holley has some EFI units that do not need a return line, but it seems like it would be best to have one anyway.

Since I am needing to change the tank, would it be a good idea to get a tank that is ready for EFI? Which of these options would you recommend?
1) Get a stock replacement and worry about the EFI later.
2) Replace the tank with one that has a return line. Add an external electric fuel pump and return line when I convert to EFI.
3) Go ahead and get an EFI ready tank now with a return line and an in-tank fuel pump. Install a regulator to reduce the pressure for the carb.
4) Screw the carb and take the plunge to EFI right now with the new tank, etc.

Thanks in advance!

 

I’m in camp 1 or 3, either one will leave you with a similarly valued leftover. A regulator would be fairly easy to sell, a leftover tank not so much. If you do EFI tank/pump/lines now, it will save you a day or two when the EFI install happens.

Go get em! Just how is up to you.

——-

 

Thanks! I had not considered resale. That is a good catch.

 

I just put a Tanks Inc 24 gal EFI in. The base kit is exactly as the name implies- cheap, universal sender and pump hanger. Upgrade to the tube style sender and ditch the ping-pong ball. It's easy to get backwards if you rush it; ask me how I know. The fittings on the pump hanger were too short to get a wrench on, as they sandwich between the trunk floor and top of the tank. Some 1/4" pipe fittings fix it, but I had to find that out the hard way, too. Also, the filler neck wouldn't seat my fill cap. Another adventure- I got the capless fill cap and neck (another "upgrade"). Other than those, it works, comes with straps, and I'm stoked about 24 gallon extra range.

 

Thanks for the recommendation. I will look into it.

 

RobbMC sells a sending unit that includes a pick up and return line that you can install in a standard replacement tank. Mine came with 1/2" in and out, with -8 AN fittings.

 

A stock gas tank is easy to retrofit to a EFI capable pump, I like my install.

 

theres a stainless tank DR Dan, Dans72 here told everyone about a few years back, very nice, and you can use it with a stock pickup for a carb or a holley in tank pump and sending unit for the sniper EFI

 

I’m into the simplest/cheapest solution. If your plans are to go EFI in the future, buy the EFI tank. Eliminate all the factory fuel lines and install hose EFI capable. Remove the EFI pump from the sender, use a section of hose to omit the pump. Connect the EFI hose to the mechanical pump. Just make sure to leave enough extra hose to make the EFI fuel connections later.

When your ready to jump into the EFI project, remove the hose and reinstall pump. Remove the mechanical pump and connect the hose to the EFI.

One tank purchase, one fuel line purchase, minimal waste of money and effort.

 

I ran a small EFI pump on a carb. You just need a good return regulator and a big return line. Anybody want to buy a nice Mallory regulator?

 

I would just clean your stock tank thoroughly reinstall and add an inline fuel filter before the fuel pump. When you decide to go efi, then change the tank.

 

Lot's of great advice here, guys. Thank you, all.

I had not considered that the stock line could be cleaned. I figured it was past saving, but that is something to look into. If it is beyond saving, I will probably just bite the bullet and convert to EFI when replacing the tank with an EFI-ready tank.

 

One other thing that I did not see mentioned; your current fuel line is probably 5/16" diameter pipe, you would want to increase that to 3/8" diameter pipe.

 

Thank you!

 

I'm in the same boat now. I have decided to go with a Tanks Inc EFI set-up with an In tank pump. Increase lines to at least 3/8. Install low pressure bypass regulator for carb. When I'm ready for EFI unit all you have to do is remove low pressure regulator and your all set to go. Go on Tanks Inc web site and they have all the diagrams and directions on a multitude of setups. Or give them a call and they will walk you through it. They do this all day long.

 

If you are going to run an in tank pump regulated to carb pressure you will not be disappointed. That said, if you do use one in a carb application, get a relay like linked below. This primes the pump for 3 seconds when you key on and then will only run the pump when there is an active tach signal. I consider them a safety measure not to be ignored.

Fuel Pump Timer Relay

 

Will do.
Very good advice !
Smart thinking...

 

Great advice! This is why I love this site. This is a totally logical, smart modification for safety that I would have likely not thought about when making the change.

 

I also installed a 10psi Hobbs pressure switch (normally closed) on the regulator, so that if the pressure ever spiked, it would kill ground to the pump relay coil. I didn't want to overload the needles and seats in the carb, washing down the bores or spewing fuel out of the vents. Captain Safety reporting for duty, sir!