ALLOY FUEL TANK SUMP / BAFFLE DESIGN

ALLOY FUEL TANK SUMP / BAFFLE DESIGN

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Discussion

M4gnu5

Original Poster:

9 posts

143 months

Friday 20th October 2017
quotequote all
I have a homemade alloy fuel tank in my westie and was looking to install a fuel sump due to poor location of pickup and starvation issues.

Was thinking of something like this. 100x100x25 situated in the middle of the tank.



Will this work? What is the usual design for these?

What is the standard baffle design? I am struggling to find anything on these....


gtmdriver

333 posts

180 months

Friday 20th October 2017
quotequote all
This is one design for a fuel tank baffle.


greenamex2

509 posts

262 months

Saturday 21st October 2017
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M4gnu5 said:
I have a homemade alloy fuel tank in my westie and was looking to install a fuel sump due to poor location of pickup and starvation issues.

Was thinking of something like this. 100x100x25 situated in the middle of the tank.



Will this work? What is the usual design for these?

What is the standard baffle design? I am struggling to find anything on these....
I tried something like this on my old race care. It work a bit better than standard but didn't completely resolve the issue.

You could combine that with tank foam and cut away the area of foam above the "sump". That would help some more.

Or you could just fit an external surge tank, like this -

http://www.compbrake.com/product/dome-fuel-swirl-p...

Steve_D

13,796 posts

265 months

Saturday 21st October 2017
quotequote all
Modifying an existing tank will be a right pain.
As already said use an external swirl/surge pot.
Fit a low pressure pump (with the required flow) between the tank and pot. Fit a return to the tank from the top of the pot. Fit a restriction in the return line to keep a positive pressure in the pot (restrictor with a 1mm hole will be OK). You don't care if very little fuel returns to the tank all you want to do is clear any air/vapour trapped in the top of the pot.
You don't say if the engine is carbs or fuel injection. You will need to add another pump of the correct pressure and flow after the pot. If it is high pressure for fuel injection the positive pressure in the pot will help avoid cavitation at the inlet to the pump.

Steve

M4gnu5

Original Poster:

9 posts

143 months

Monday 23rd October 2017
quotequote all
Thanks for the replies guys.

Car runs a set of Jevney carbs and a Facet fuel pump. There in only a single feed line from tank to pump and then a single feed from pump to carbs. No return lines.



The tank is home made, but the outlet has been positioned incorrectly as shown in picture. The outlet is at the front R/H side of the tank and this is causing fuel starvation on R/H corners and up hills, but running OK the rest of the time.

I can get the sump fitted FOC from one of my work contacts. Hopefully this will be a quick / easy / cheap fix. Certainly worth a try before thinking about a swirl pot.

Will post update in due course......

CrutyRammers

13,735 posts

205 months

Monday 23rd October 2017
quotequote all
Mine has a similar thing:


I'm not actually sure how the baffle looks inside, (I don't think it had any movable doors but could be wrong), I've never had starvation on track. It was done by Allyfab who was a good chap to deal with.

pigeondave

216 posts

235 months

Tuesday 24th October 2017
quotequote all
Drill a smaller hole than the sump being fitted. Ive got a 50mm hole and a 100mm sump, this allows fuel in and not to slosh out.
Also think about -AN fittings welded on to the side of the sump it makes for a neater finish.
https://www.flickr.com/photos/pigeondave/927779056...

M4gnu5

Original Poster:

9 posts

143 months

Friday 3rd November 2017
quotequote all
Sump now fitted and car running. Went for a 120x120 square sump with a 90x90 square internal hole





Not sure if it will solve the problem. Time will tell....

Fury1630

393 posts

234 months

Monday 6th November 2017
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My Fury's got pretty much the same thing - a little deeper maybe, but it works just fine.

JohnMcL

147 posts

150 months

Tuesday 14th November 2017
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Hi all,

Take a look at this. No sumps or baffles. Picks up every last drop.

https://www.holley.com/products/fuel_systems/hydra...