Sunday, July 14, 2013

MGB GT gets an FIA rated ATL Fuel Cell

At the LeMons 2013 Capitol Offense race, we were politely told to fix the ass end of the car, as described in our race report.

What we did...


  • ATL 15 gallon FIA rated LeMons Legal fuel cell, direct off the Lemons web site in order to guarantee this cell is acceptable. 
  • Mounted in the OEM gas tank location (a little higher so we don't drag on bad entries to The Karussell!)
  • Using professional Speedway Motors Fuel Cell Bracket mount bolted to the frame
  • We have the OEM back bumper and an additional internal bumper (built from old roll cage material) behind the cell to help in heavier fender benders
  • No splash bulkhead required (though we may add one later)

The fuel cell install has begun!

Here's some pics, not done yet but here it is so far:

Where the mount meets the car; long horizontals (marked '1 inch steel' here) were cut to 38 inches so they overlap the upper frame for mounting. The section of roll bar you see was existing, and has a vertical piece (inside, between two frames) about 2 inches high that welds it to the lower frame.
ATL Fuel Cell in an MGB GT hatchback

The horizontal side pieces are used from Speedway unmolested, however the verticals were cut down to 8 inches and re-drilled (oddly, one of the eight holes was the wrong size from the factory):
ATL Fuel Cell in an MGB GT hatchback - side traps
Here is the first fitting, without the improved fuel cell cage frame pieces. We could not move it forward any further without hitting the differential! It's in the OEM position, so will be OK. Well, we could move it forward, but it would be sitting on the drivers shoulders... and that's just ridiculous since we already have a cool-shirt system.
ATL Fuel Cell in an MGB GT hatchback - snugly in place

Here is the original frame from Speedway Motors; note the two upper short horizontal bars (outermost) are held in place by magnets in this picture; we were fitting the fuel cell and moving those pieces around. The holes to mount those pieces permanently have not been drilled yet, we are waiting to finish the extra L-Channel trap frame before doing so, in order to ensure a nice tight fit.

Here are the pieces of the L-Channel trap frame (I don't know the proper name for it, but it is made of L Channel steel and it traps the bottom of the fuel cell, so that's what I am calling it). We made pieces to go around all the edges on the bottom and then up the sides on the corners. Measurements in inches are 24 5/8 (two), 18 1/4 (two), 9 1/4 (four). The vertical corner pieces do not hit the upper flange, we did not want that to be a stress point.

Here is the cage tack welded, before complete joint welding by pro:
The Speedway Motors Fuel Cell Cage - augmented with angle iron to protect edges, tack welded, prior to full weld.

Update 2013-08-06 - Cage back from the welder!

Painted, mounted:
Fuel cell cage, resting in well; about 6 inches higher than normal MGB gas tank and a bit more forward

Looks simple, doesn't it?

That vent line is just a place holder

MGB Fuel Cell corner with Grade 8 mounting hardware
Detail, underneath: corner protection evident, note cross bar bolted and welded! pffft
In situ; pay no attention to that missing vent line....
Front the top
Update 2013-08-07 - some extra pics for the curious


(more pics to come, as we endeavor to make NJMP!!!)


Some links to 24 Hours of LeMons Forums regarding Fuel Cells:

Shopping List:

Fuel Cell Rules & Notes from 24 Hours of LeMons site:

  • Common Tech Failures:  Fuel cells.  If the cell is not an FIA certified rubber bladder cell (Fuel Safe or ATL) then it must have a sealed metal barrier between it and the driver, even if it is in a metal can.  NO EXCEPTIONS!      This means most cells from Jazz, RCI, Summit, Etc.   They all need a metal bulk head between the cell and the driver.   A fuel cell install is always judged by its quality of install and is looked at by the race manager, The bar is high, do a good job.   
  • How NOT to Fail LeMons Safety Inspections: Cell can't be too low (punctures), too high (rollovers), and must be far enough away from edges to avoid damage during typical accidents.
  • Rulebook: (note: always check most up to date rulebook!) - 3.25: Fuel Tanks/Fuel Cells: All fuel systems, including OE fuel tanks and aftermarket fuel cells, must be sound and in good working order. Maximum allowed capacity is 24 gallons or less. Fuel tanks or cells must be completely behind, or completely in front of, the driver (unless OE parts in their OE locations). No second fuel tanks allowed (unless OE parts in their OE locations).
            3.25.1: Aftermarket Fuel Cells Versus OE Fuel Tanks. Fuel cells are allowed,but they are NOT mandatory. Don't make the rookie mistake of assuming that anything billed as a "fuel cell" is safer than a sound OE fuel tank.High-quality, professionally constructed, correctly installed fuel cells tend to be safer than OE tanks; cheap and/or poorly installed fuel cells tend to be less safe than OE tanks.
            3.25.2: Fuel Cell Installation: If you decide to install a fuel cell, it must be securely mounted in a professional manner and must be installed in a safe location where it won't be damaged in an impact or drag on the ground if the car leaves the track. All aftermarket fuel components must use threaded fittings and appropriate hose types, and must include all appropriate racecar-quality vents, valves, and other safety features. Fuel-cell installations will be judged on their overall execution and apparent safety. Cars whose fuel cells do not feature internal foam, a puncture-resistant bladder, and/or metal encasement are considerably more likely to fail tech inspection.
    Also this section spells out an FIA certified fuel cell if it is going to be sharing the passenger compartment with the driver (or in the rear hatch area in a hatchback)
    3.18: Fuel Bulkhead: The fuel-tank area must be totally separated from the driving compartment. For example, if the fuel tank is in the trunk area, any openings between the trunk and the cockpit must be permanently sealed with bolted, riveted, or welded metal panels. OE fuel tanks that are separate from, and located completely below, the trunk floor or rear-cabin floor are acceptable. If the fuel tank can't be completely separated from the cockpit by metal panels, a metal-encased, FIA-certified fuel cell with all related compliant fittings must be used.

1 comment:

  1. As you have given the photos its seen good and the cage is not possible to make without flange bolts anyway but you have done awesome work.

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