C3 Gas tank upgrade??
 

Is it possible to install a bigger tank than the stock tank without losing
the spare tire?

I bought one on Ebay last year that was advertised as 24gal , but it measured exactly the same size as my 52 liter tank.....I got taken.

In the pics of the auction description, it looked like the tank would be deeper
and you would have to lose the spare wheel to get it to fit. I probably paid for a 24gal tank and got sent a 13gal tank.....too much shipping to send it back, so I sold it locally to someone who wanted a stock size tank.

Still wondering though if a bigger tank could fit!

Re: C3 Gas tank upgrade?? (Summerfun)
 

OK I'm confused. Isn't 52 liters about 13 gals? (.26 x L = G). '74s did not come with a 13 gal tank. I'd check Quanta. http://www.quantaproducts.com




[Modified by KenSny, 9:50 AM 5/11/2004]

Re: C3 Gas tank upgrade?? (Summerfun)
 

Awwwww crap ... one of our Aussie friends here upgraded to a ~25 gal tank IIRC. It was years ago when I saw that thread though. Maybe he'll chime in? Hellooooooooooo?

Re: C3 Gas tank upgrade?? (KenSny)
 

The 74 came with an 18 gal tank. Some later cars had a larger tank due to the fastback roof line allowing more space at the top of the tank.

tom...

Re: C3 Gas tank upgrade?? (Tom73)
 

My tank is not the original tank!
Previous owner (more than 9 years ago) installed it out of , I believe, an early 80's Vette....but I don't know

It takes just over 50liters however.....and drives me crazy, for I can hardly get 200km per tank....if I drive nicely!!

Re: C3 Gas tank upgrade?? (Summerfun)
 

I've got an 18 gallon "bladder" tank in my 76.

Re: C3 Gas tank upgrade?? (KenSny)
 

BTW, I just assumed that the tank that I had bought was 13 gal, as it was the same size (I measured it) as my current tank of 52 liters.

Just checked my file: The tank I had bought had the following dimensions:

38"longX15 3/4"wideX11 3/4"tall.......11 3/4" tall sloping to 7" front to back

Re: C3 Gas tank upgrade?? (Summerfun)
 

I'd check Quanta for the dimensions of their stock replacement tank. They were running about $200 (maybe less) when I seen them at Carlisle. I think they are more than 18gals, close to 20.....

BTW: Those dimensions are pretty close to my '75 (which I currently have on the bench) and it holds about 18gals. A '74 tank will bolt up in my '75 car exactly the same except the the sender is on top for a 75 and on the bottom for a '74.

I don't think you can get a tank from the later cars with the slope/hatch glass. The filler neck would be in the wrong location on a '74 car. You would have to modify the deck.



[Modified by KenSny, 11:31 AM 5/11/2004]

Re: C3 Gas tank upgrade?? (Summerfun)
 

Fuel tank capacity is all over the map on these cars for some reason. I have the same range problems as you with a advertised capacity of 16 gallons US, but I've never been brave enough to use more tha about 14.2 gallons. That works out to 110 - 120 miles between fill-ups :mad .

There was a thread about a year ago on this and a custom made 28 gallon alloy fuel cell could be special ordered for around $600 dollars US from an outfit in Los Angeles somewhere. It was attractive to me because of the safety issue and better range, but the spare has to go as it drops down into that space. I pulled my spare and carrier a long time ago to lose the excess weight, so it's not an issue for me.

Hans

Re: C3 Gas tank upgrade?? (Wrencher)
 

I had a shop build me a custom aluminum tank. It has internal baffles, an integrated sump and holds a little over 21 gallons.

Edit: It also clears the spare tire.


[Modified by zwede, 10:40 AM 5/11/2004]

Re: C3 Gas tank upgrade?? (zwede)
 

Oooh, got any pictures? Is it wider and longer? Nice that it clears the tire.
How much that set you back?

Hans

Re: C3 Gas tank upgrade?? (zwede)
 

Zwede,
It would be GREAT if you could give us the measurements of that tank!
If it is not too much trouble!

It installs from the bottom without difficulty and clears the spare too?

Re: C3 Gas tank upgrade?? (Summerfun)
 

Here's a pic:

http://www.corvetteforum.net/c3/zwed.../efi/tank2.jpg

It is fairly close to stock width/height. The sump holds almost a gallon and I guess straightening out the corners bumped capacity some also. Yes, it installs from the bottom and clears the spare. Also uses the stock sending unit and filler neck.

As for the price, the fabricator is a friend of mine and we swapped favors, parts etc and worked it out that way. He said he can make more of them for about $400 but he's in Europe so shipping would be a killer. I took mine as checked luggage on the plane during a business trip there.

Re: C3 Gas tank upgrade?? (Summerfun)
 

I replaced the tank in my 71 a couple of years ago and researched this. I came to the conclusion that I could use a Quanta 71 tank and increase the capacity by modifying the neck. Pre 71, the neck was short and almost all 18 gal were usuable. 71 and post used a longer neck to permit an air pocket for venting purposes for emissions reduction.
Since I seldom dirve the 71, I installed a shorter neck and got the 2 gal usable back.

Re: C3 Gas tank upgrade?? (zwede)
 

zwede - nice tank :thumbs:


:lurk:

Re: C3 Gas tank upgrade?? (Summerfun)
 

Was it US gallons or Imperial gallons???????

Re: C3 Gas tank upgrade?? (zwede)
 

Here is a thread from last year made by a talented guy here on the forum
http://forums.corvetteforum.com/zerothread?id=595064

:cool:

Re: C3 Gas tank upgrade?? (71coupe)
 

Thanks 71coupe,
I'll send Eric an e-mail and see what he has to say!

Re: C3 Gas tank upgrade?? (Barry)
 

Barry,
I was talking US Gallons.

I know, according to the other posts there must be something wrong inside my tank.....bladder folded on itself or something of the sort, as I can not get more than 52 liters in there. They all say 18 US gal....which is 72L

Re: C3 Gas tank upgrade?? (Summerfun)
 

Now that puts a whole different slant on things. Wish you would have said you have a tank with a bladder. OF COURSE a 74 DID NOT COME WITH A BLADDER TANK. So you must have some aftermarket installed.

My '75s bladder collasped so bad that I could only get 7-8 gals in from empty. Pulled the bladder. The tank was clean inside so no need to replace. Now I just need to get it back in after I replace the rear bumper and such.



[Modified by KenSny, 8:23 AM 5/12/2004]