Fuel Vent Question/Newbie

[Dnrice]

As some of you know, I am new to this forum. I ran across the SLC when surfing the web looking at other replica/build companies and have fallen in love with the SLC's exotic look.
I have been reading build threads, searching using the search engine and wanted to start off before going full in with the purchase by studying different stages of the build. IE. Stage 7 - Steering, Stage 8- Brake Components etc...
One area I have been reading about is the Fuel System.

Can one use a fuel cap with a vent vs. venting the fuel tank? Which fuel cap would fit? Also, if using LS376, do I have to use a surge tank?

Thanks, Dnrice (A Newbie)

 

[Jack]

A fitting may be welded to the fuel fill adapter and a line ran to the tank, or a seperate vent line run. Swirl/surge tank recommended for any LS engine. Not too difficult to do. There are a few SL-C's without it though.
THe fuel system is straight forward, just a little tight on packaging depending where you wish to place the components.

 

[Alex]

I sumped my gas tank so I didn't have to do a surge tank. Vent is simple; just weld a - 8AN fitting on the top and run it, through a filter, to the ground

 

[Dnrice]

Thanks for the responses. Didn't even think about using the sump.

 

[Bill]

I've been thinking about going with a sump as well for my street SLC.

Is it worling ok for you?

Do you have any PICs of the added sump?

 

[Alex]

Sumpity sump sump

I know some people think their swirl pot is better, but I'll put up my baffled 1/2 gal. sump over the excess plumbing anyday

 

[Bill]

Oh my goodness! You've done some significant surgery...Nice work

Does the sump depth extend all the way down to flush with the bottom of the car, or did you leave some space for safety against a possible road hazard?

 

[Dnrice]

Very cool Alex! I assume you hired someone to do the welding or did you do it? And I am also wondering the same question as Bill about possible road hazzard.

 

[Alex]

My car came with an aluminum plate riveted under that area, so it's protected. I drilled a few, erm, speed holes (ehehehehe) under it incase it ever leaks so fuel won't puddle there...it'll leak out the bottom and at least I'll know I have a leak

 

[Fran Hall RCR]

So Alex...making a new fuel tank is easier than installing a few fuel lines and plumbing a surge tank....HHHMMM...not convinced mate..

 

[Alex]

So Alex...making a new fuel tank is easier than installing a few fuel lines and plumbing a surge tank....HHHMMM...not convinced mate..

Under Alex-style logic, yes, yes it is

Sometimes I look back at some of the things I did and wonder just how bored I was in order to come up with some of my ideas that resulted in countless hours of frustration

 

[Mike]

The surge/lift/swirl tank is supplied low pressure fuel from the gas tank and also from the fuel return which pumps fuel back to this smaller (always full) tank....you will always have fuel in the surge tank.

 

[Troy Truglio]

I have been using a surge tank for about 2 years now with no issues in my other mid engine track car. I got the one for the SLC off ebay for like $70, some an lines and fittings with the pumps and done. I have to wire up and hook up all the hoses for the pumps anyway so I do not see it as much more work at all or adding much time. Now cutting up the tank and making sure it never leaks, that I do not think I want to do, yet you did do an amazing job. I just see the surge as way way easier and might even be a better solution for the track and street.

BTW- I spy an older BMW, maybe E30.

 

[Bill]

Sump vs surge tank

My FFR '33 Hot Rod has a fuel tank very similar to the SLC (longitudinally long with a flat bottom. I have never experienced fuel starvation in hard cornering. The one complaint I do have is that I can only get 12 gallons out of the 15 gallon tank. This where a dropped sump section comes in handy.

My Hot Rod corners quite well, but no where near the side Gs of the SLC. In SLC hard cornering the fuel sloshes from side to side, but the internal baffles slows the movement. Unless you are running with a low fuel level, the sump should stay full.



The above are all fine for a street car, but a track car has different needs and a surge tank is probably a better choice:

• If you are doing skid pad testing, a surge tank will feed the engine longer (fuel stays on one side of tank for an extend period).
• To save weight on the track, you may want to run with less fuel in the tank.
• Except for endurance racing, you don't care about getting full capacity from the tank.

I'm building a street car, so I think I'm going to add a sump to the tank before I put gas in it for the first time. I know a local aluminum fabricator who specializes in fuel tanks and his rates are very reasonable. If I experience starvation sputter, its easy to add a surge tank later.

 

[Cam]

The day i added the swirl pot i never had any starvation problems. Before that, it would cut out pretty easily on braking and left turns, even acceleration unless you had 3/4 of a tank left. The SLC puts out more G's on cornering and braking than any production car. OK maybe short of an Enzo. I guess a sump with a bunch of baffles can handle that G load but a swirl pot is pretty easy to put in line. Plus it gives you an extra half gallon of fuel in the system...

 

[Dnrice]

Thanks Cam. Learning a bunch on this forum. Very cool.