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InertiaWerks, Virginia Beach, VA

Parts supplier, and consultant

Updated - 06/09/2005

Fuel Cell Installation - Porsche 944

•  ATL - Sportsman Fuel Cell

  • 8 Gallon capacity

  • Internal Surge Tank

Remove original Fuel Tank...

• You'll have to remove the Transaxle first.  We usually look for the easy way, but the tank is molded to fit so tight we didn't even try this time.

• Use some plastic bags to cover up the bell housing and CV joints. 

• We will be using the stock fuel filter, (silver can near top) and the stock fuel pump.  The fuel pump will be able to stay in the original location, there will be just enough clearance.

Cut a Hole...

• We taped up some plastic sheeting to reduce the sparks and grinding material ending up in the passenger compartment, and pulled the fuel pump and lines out of the way.
• Measured 23", from the back of the spare wheel well towards the front of the rear deck, and marked a line.  This line was just past the 4" circle cutout for the fuel sending unit, and just before the fill tube hole.
• Used a air-powered grinder/cutting wheel, and made the rough cut to remove the top of the rear deck.
• Use the grinder to smooth out the edges.
• Put the transaxle back in, and take a few pictures.

• We used 1" square tubing.
• Along the 'short' side, we drilled 9/16"  holes in the top of the cage.  This would let the original bolts and nuts recess into the cage, and leave the top flange supporting the weight.
• It also allowed us to weld the front and rear upright on the center line.
• Along the 'long' side, we drilled 1/4" holes, and replaced the original fuel cell bolts with 2" long (grade 8) bolts to go through the cage, and bolt the cell to the cage.

• We needed to replace some of the stiffness between the frame rails, and provide support for the fuel cell.
• So we cut some flat steel, 3" squares, and welded these to frame rails, then welded 2" angle iron to these squares.
• The angle iron runs from passenger side to drivers side, between the frame rails, and is about 1/4" below the top of the rails. You can just see the angle iron running under what is left of the rear deck. 

• Drop in the cage, and tack it in place.
• Here the support from the angle iron going down to the cage, is not yet present, and the cage is only spot welded to the side frame, and the rear. 

• Here you can see the supports coming down from the angle iron to the cage.  They are notched out so that the back of them goes up behind the angle iron, and provides a little more welding surface. 
• The fuel pump is wrapped in the plastic bag, but will be able to remain in this location.

• Here you can see another 3" flat steel piece behind the back support that will be the anchor point for the drivers side rear of the cage.  Along the top right, you can tell were the spare tire well was cut away.

• Nice white paint job...
• A 1" square tubing was added, going from the drivers side frame rail to the cage.
• Initial plumbing test...just to check the line locations.
• The red hose is 1/2" fuel line from stock fuel pump (blue item in bottom photo). 
• Not shown, but there is a brass union that connects the original return line to the 3/8" black line going to the fuel cell return.
• The fuel pump will be left in the original location, but the red 1/2" line here will be replace with some black 7/16".