Fuel Cell

15 Jan 05 - Fuel Cell Installation

16 Gal cell (25 x 17 x 9, # 290108) with foam and GM sender from Summit Racing. A side filler neck is planned. We used the straps from Summit too, but they had to be re-bent and drilled to fit.

We started by cutting off the Mustang tank mounts in the rear and trimming the front mounts. A cross member was added to the existing front mounts to support the fuel cell straps.

Spacers keep the tank from being crushed while allowing the bolts to be fully tightened. Someone from an online forum gave us a good tip about supporting the top of the plastic tank to keep it from collapsing. Several other members provided tips and info too, thanks to everyone.

More test fitting, the mounts are not yet complete.

The pre-filter will mount to the tube on the passenger side.

Done!

28 May 05 - Fuel Pump and pre-filter.

The Walbro GSL392 fuel pump is mounted on the 4" frame tube under the passenger side seat. We wrapped it in the foam rubber tube it came with to cut down on the noise. The thin sheet metal bracket will also cut down on the noise transmitted to the frame.

The GSL392 pump puts out 255 lph with a cutoff pressure of about 145 PSI. I calculated that we need 43 gph for our horsepower goals. 15 Oct 06: Note that the high pressure pump has since been changed to a low pressure Walbro pump to support a carburetor. Lucky that the Walbro pumps all share the same housing and are the same size!

We made couple of billet brackets to hold the pre-filter on the side of the fuel cell.

We used a product called Everbrite to clear coat the polished brackets and Forte degas tank. I saw Everbrite recommended on several machinist forums, hope it works! One covering coat with a foam brush is all we put on; since subsequent coats soften the previous ones. We also thinned it about 10 percent with Xylene -- contrary to the instructions. Everbrite is more forgiving than POR and other clear coats, its one part, it comes off easily with Xylene, and touch ups are simple because it softens the existing coats and blends in. Like most clear coats, it magnifies any imperfections in the surface.

	Yeah, the degas tank was powder coated, we stripped it and polished the tank. The whole purpose of the powder coating was to cut down on future maintenance (polishing). Hopefully the Everbrite product will prevent any more polishing. Time will tell!

The secret to rivet nuts -- get the knurled ones, they are less likely to spin in the hole. Coating them with POR will not only help prevent rust, but lock them in place too.

The trick to installing the split ring for the 2" fuel filler neck. Cut the ring in half and use threaded rods to hold it in place -- especially when you close off the original top filler hole with a titanium plate.

The completed bracket and filler neck.

5 June 05 - Fuel Lines

What makes most tubing "flare-able" is the absence of an inner weld seam so the sealing area can seat properly. A few seconds with the Dremel removed the seam. You can also get seals from specialty shops, like Aircraft Spruce. Update: after you remove the seam, put the tube back in the flaring tool and run the tool around the flare to make the flare round again. You also might want to polish out any sanding marks with the Dremel and some polish.

Note that fully hardened tube will not flare! It will probably crack.

AN 8 is overkill, but it looks tough. I made two more brackets to hold the bulkhead fittings in place.

Hard lines done!

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5 June 05 - Started the Flexible Fuel Lines

We are using Ear's Super Stock hose around the IRS area and in the rear. Here's a tip we got right from Earls' Engineering Department. Heat the very end of the hose with a heat gun to make it soft so it will slip right on easier; this applies to most any hose, not just the Super Stock. In addition, tighten a plug in the end of the fitting to keep the tube from spinning while you are trying to twist the hose on. Use the recommended hose lube, yes its oil, but with special additives to make it more slippery; you can actually feel the difference. (I doubted it too) Wear a pair of non-slip rubber grip gloves from Wal-Mart or Home Depot when you push the hot hose on the fitting.

The Earls Super Stock hose is the same as their stainless braided except that the stainless braid is replaced with another coating of rubber. We are hoping the additional rubber layer will prevent the gas smell from leaching out and also keep the hose from wearing thru the paint up under the IRS. But more importantly prevent wearing a hole in the plastic fuel cell if it happens to rub against it.

Up front in the engine compartment, the plan is to use Earls Pro-Lite hose, nylon not stainless outer braid and 1/3 the weight of stainless braided hose. Airplane guys love it.

Apparently Earls had a bad batch of blue Super Stock -8 hose, which was the reason I ended up calling the their Engineering Department in the first place. The date code of the bad hose is 10-Q499. The hose will not allow the ends to go on (no matter how much you push, lube, heat the ends, curse or throw things). If you are using this hose and happen to get this date code, call Tech Support at Earls and they will exchange it. You might have to go thru Engineering first (I did) because Tech Support was not aware of the issue. Earls stated the bad hose is only the -8 AN 10-Q499. FYI, I got mine at Jegs, Summit was out, don’t know about other shops. Earls stated this batch was pulled from store shelves years ago, Jegs must not have got the word and it laid around in the warehouse.

21 June 05 - Flexible Fuel Lines

Fuel lines are pretty much done.

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The middle line is the return. The line to the left is a vent. The vent is a -6 AN rollover vent valve from Jegs. (Yes the original Mustang tank has a rollover vent valve)

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We put a few loops in the hose to help keep the fuel from sloshing out of the tank and ran the line to the bottom of the tank. The aluminum canister is a fuel filter stuffed with activated charcoal to keep the smell down. (Note this has been changed!) The brass thing on the end is a filter to keep dirt and gunk from getting inside the tank as it sucks in air to replace the used fuel. There is also a smaller similar filter on the differential vent. The main thing I would do different is to use an aluminum fuel cell.

Don't panic, the e-brake cable rubbing the CV joint in this picture is not connected or routed properly.

Here is our fuel system plumbing diagram. Note that the short AN-8 hard line in the front was later replaced with braided. As mentioned, the small filter was replaced with the original purge canister as the little filter did not hold much charcoal and was overcome by the gas fumes.

Update 7 Aug 06: Currently both the Earls Super Stock hose and the Russell Pro-Flex allow the gas smell to leach out. They will be replaced someday with a Teflon lined hose.