Now that my '77 chassis is a completely rebuilt roller, I'm moving on to the fuel tank.

I'm installing an '86 Corvette TPI engine from which I'm removing all emissions to include the carbon cannister & its lines.

I know I'll need a different fuel pump to handle the TPI; however:

...can I use my stock '77 fuel tank? Or will I need something else?

...if I can use my '77's tank, is there anything I need to do to it?

 

It all depends on what you are going to do for a fuel pump. If you plan on using the factory fuel tank...and have an electric fuel pump modified so that it is installed inside the fuel tank...like GM does....then you may need to get a new fuel tank and have it modified...because I do not know anybody who would work on a tank that had fuel in it...due to possible welding of a baffle plate / resevoir inside the tank so the pump would not starve for fuel while turning a corner.

If you plan on using an external fuel pump...just be aware of possible "vapor lock" due to the pump getting hot. Which occurs around where I live in the summer months. You will also need to be FULLY aware of the pressure that the pump is producing and making sure that your fuel system is CORRECT...so you do not turn your car into a "roman candle".

You should also make sure that you incorporqate the "oil pressure/fuel pump cut-off switch" like GM did...so that if your engine looses oil pressure or dies...while the INGITION is still on...you fuel pump will stop running. This is to keep it so if you were hurt...and unable to turn off the ignition...the fuel pump would not pump fuel into an area of a potential fire....or feed one that has begun. It would be wise to make sure that this safety feature operates CORRECTLY.

You may be able to take measurements and see if a fuel tank off of an 85-96 would work. That way everything is as it should be.

Just a reminder...be aware of the fuel pressure and how you make and modify and clamp fuel lines and hoses together. When I do these conversions...I am SUPER **** about this area....because I can not afford to have any problems...and the system must last a very long time without any problems. I even incorporate the factory fuel filter and lines that feed the fuel rail/return....it is a pain...but I feel it is a MUST.
"DUB"
"DUB"

 

I was planning on using my original '77 tank with an external fuel pump but when I opened the meter to see what the inside of the tank looked like, I found that it has that formed plastic liner the factory used....will that cause a problem? I am also concerned that using an external electric fuel pump sucking fuel up to the top of the tank through the factory tank meter might also cause problems.

A second option I was thinking about was to buy a '73 tank that has the fuel pickup in the bottom of the tank....I thought that might work better with an external electric pump than my '77 with pickup on top.

 

The external fuel pump will not suck the liner or cause fuel to be at the top of the tank. Your sending unit should have a filter sock on it and this will prevent any issues. The pick-up on your sending unit is on the bottom of the tank...so fuel can not get to the top...even though it is being sucked to the top of the sending unit...it is not being sucked to the top of the tank. Just do not allow your tank top run low on fuel...so you do not starve the pump.

If you choose to change the tanks ...that is your choice...due to the sending unit being on the bottom. Once again...I prefer the pump IN THE TANK. By changing the tank to the earlier design....you will loose the restrictor that is in your filler neck that was put there due to being an UNLEADED car...and so you could not put LEADED fuel in it. You may want to see if this area is inspected for safety/emission inspections in your state. In my state...they CAN NOT be ALTERED.
"DUB"

 

Yep, I'm torn here....keep my tank & add an external electric pump..... or switch to an earlier tank that's not got the liner so I can cut a hole in the tank to insert an internal pump.....I don't believe I can cut my tank to insert an internal fuel pump.

Glad to hear that an external electric pump won't suck the liner....I like the idea of keeping my tank and adding a good, powerful external pump.

 

I welded on used tanks.Either send it out to be boiled at a radiator shop or flush it real good over and over again.

 

No body has mention Noise yet. A inline pump most often will make a very anoying buzzing sound. You will think you are in a Dentist Chair. Putting the Pump in the tank has a lot of advantages. The Late Sharks have a larger Fuel opening in them and You can place a pump in the Tank with out any Welding. I thought it was 78 when they went to the Liner but you say your 77 has it so dose it have an opening big enough to slide a Pump in?. Keep in mind this is what GM did in 82. The 82 is not known to be the best Pump however I have had good luck with a Bosch. I don't think a 78-82 Tank will fit your Car.

 

The 77 has a large enough opening to mount the pump in the tank. You need to get creative with the mounting. You could adapt a modern pump that has a sump built around the pump. No welding required in the tank. 77 has a blader which will have no effect on the pump

 

With Artsvette73 & Gale banks 80',

External pumps are noisy...even if you insulate the mounting as AWESOME as possible....they still "buzz".

And youopening should be large enough so you can get a pump for a 85-96 Vette and mount it to your sending unit. And also incorporate a resevior so you do not allow the pump to be starved for fuel. The only tricky parts I see is making sure that your electrical "bulkhead" connector that would go through the mounting plate of your current sending unit would need to be sealed well...along with the fuel resevoir for your fuel pump...would need to be CAREFULLY manufactured out of a material that would not tear or damage your inner liner....or at least have rubber pads on it so it would not damage the liner in the future...even though it would be vibrating when it is running. OR...reinforcing the tubing...or adding straps to the pump mounting area... so it can handle the weight of the resevoir and pump that would be suspended just above the liner. A job that sounds like CAREFUL measuring and testing....but I FEEL it would be worth it. I MAY be overthinking this...BUT it is your fuel system....NO ROMAN CANDLES!!!!

IF you can get a 78-82 tank to fit...then your worries are over...because you can then purchase a sending unit for a 1982 and install a pump for a 85-96 vette in it.

Good luck in your decision...and I hope that everything goes well..in what ever way your choose to go with this issue.
"DUB"

 

I used a late model GM f-body in tank fuel pump. Here is the link were I got the idea form and the mounting ring.
http://www.vetteworksonline.com/ls1_conversion_fuel.htm
And you can weld on fuel tanks they just have to be flushed properly and if your still feeling skittish fill them most of the way up with water before you weld.

 

I went with the Stock 82 Pump and sending Unit to start. Its pretty sleazy built so its more of a Pattern to build Your own but you don't even need that. I just built a copy of my own out of Stainless and used the Bocsh Pump. 1/2" Fuel line comes out the top just like stock but mine is An Thread with no push on Hose. I wouldn't get to uptight about Fuel Starving the Pump as long as the inlet is very close to the bottom. The stock 82 has no baffels what so ever. My Suction Line is a Tee and it Stubs out a bit eitherside laying right on the bottom. I have autocrossed and havn't had any issues.

 

That's a great setup....when you cut the hole in the tank & its liner, how do you keep fuel from getting behind the liner & push it away from the tank?

 

Or is it possible to cut the pick uo off & add an internal pump to it?

 

Yes Sir: Call Rock Valley and have them make you a new fuel tank out of Stainless Steel With new baffles and the right fuel pump. They already have the plans for them I do believe. Have a great day. Gene

 

So, I'm hearing the majority tell me to go with internal pump....as my '77 tank has the liner, I'm going to need a tank without the liner (they're always on ebay) so I can cut a new hole for the pump.

doctorgene: Does the internal pump from Rock Valley have a float?

& it would be nice if they had a pump/float setup the size of the opening in the '77 tank.....guess I've gotta call them tomorrow....no reason to continue working on my tank until I get some more answers.

 

It sounds to me that the later Tanks with the Liner have the larger opening. So as long as Your tank is in good shape you don't need to buy an earlier tank with a small opening so that you can cut a large opening.

 

True, my tank has the larger opening...problem is, I don't know of a fuel pump that will go in & share the area with everything that's underneath the lid.

 

Since they never answer their phone, lemme ask you a question - did the setup come with a float & connections for the fuel guage wiring?

 

An electric fuel pump and wiring can be incorporated into your original sending unit.
"DUB"

 

Yes Sir: You are doing the right thing, by calling Rock Valley... Have a great one. Gene