Project COBRA'33 Project COBRA'33
Installing the Fuel System
The Fuel System on our car is fairly complex, and involves many parts and different areas. The first thing one thinks of when you mention the fuel system is the delivery of the fuel to the engine. I suppose this is only natural since this is what most people see, but there are many areas of the fuel system besides the the most obvious.
Here are the main areas of a fuel system:
a. Storage
b. Supply
c. Return
Storage: This involves the safe storage of the fuel, it's Containment, Venting and baffling.
Supply: This would be getting the fuel to the motor. You have Cleaning, Pressurizing, Containment, Direction and Regulation.
Return: Here we focus on the UN-needed fuel and returning it to the fuel tank. You have Containment, Cleaning, and Direction.
Storage
This starts in the "Frame Building" time frame, we must fit the Fuel Tank to the frame and make sure it has nothing to interfere with it. In our case the fuel tank fit the frame just fine, it was the rear-end the gave us the problems. Since we decided to use a Winters Quick Change Rear End, it created a problem for us with the fit. The quick change rear end is much longer at the center section then a stock or more common 9" rear end. It was this projection of the center section that interfered with the fuel tank. The fuel tank hit the center section of the rear end at all times, and had to be modified to clear. We had to remove a 12" wide x 6" deep x 10" high section from the tank. This sectioning gave us the necessary clearance needed to re-use the fuel tank . Next up was to modify the fuel tank to except a modern Fuel Injection System. Most fuel injection systems require a tank mounted fuel pump, with very high pressure and flow capacities. The tank also has to have a return fitting, to accept the UN-used fuel. As a precaution, we used some Red-Coat to seal the inside of our fuel tank. We had to clean out the tank as best we could, and make sure it was completely dry, then pour in the tank sealer, making sure to rotate the tank so the sealer could reach every part of the tank.
These are pictures of the stock 1933-34 fuel tank we used in Project COBRA'33
Here's our tank after the modifications have been made. This recess was necessary because the Winters Quick Change Rear End was to long in the center section and was hitting the fuel tank.
We went to Tanks, Inc. for there in tank fuel pump kit that provides all the necessary parts to convert our stock steel fuel tank to the type fuel tank used for fuel injection systems. The kit comes with a Walbro 255 L/hr fuel pump, fuel pump stand and well, vent, return and supply fittings and the correct cap to seal everything up. To install the kit, you most first cut a 4-1/2" hole in the top of the fuel tank. I used a 4-1/2" hole saw and it took less then 2 minuets. Next you must fit the pump stand and well to the tank. We had to shorten our stand to accommodate the rather small tank we have. Next lay-out the 16 holes that will hold the cap on and drill them to the right size, it works best to use the cap as a guide and simply mark the holes with a felt pen, and drill. Once that is done, fit the filter to the bottom of the pump, install the foam rubber sleeve over the pump (it acts like a muffler making the pump more quite), hook-up the fuel hose and secure the pump to the stand. Now just drop the pump-stand-well assembly into the fuel tank and at the same time, position the threaded collar ring. Use one of the longer screws to get started and then work your way around the cap, installing the screws and keeping the collar ring lined-up. It may take some getting use to, it took us a little while till we figured it out, just take your time and work from the end of the collar to the other end of it. Once all the screws are in, you Will need to go completely around the cap 4-5 times, each time tightening the screws as much as you can. They pull up as a unit, so take your time and be patient. Keep going around the cap till the gasket is uniformly crunched.
This picture shows the 4-1/2" hole we had to cut into our fuel tank to accept the in-tank fuel pump, and it's fuel pick-up well.
This is the fuel pump kit we purchased from Tanks , Ink.
Now that our tank has been modified, sealed and readied for fuel injection, we can mount it to the frame. They make special hardware packages for the attachment hardware. Basically they use a small spring to separate the fuel tank from the frame, and these kits can be bought anywhere they sell 33-34 Ford parts.
SUPPLY
The supply system is everything from the tank forward to the engine. This includes the tubbing, hoses, fittings, pumps, filters and regulators.
Our Fuel System starts with a Stainless Steel Braided Hose that attach's the fuel tank fittings to the frame rail, by use of a Bulkhead Fitting. We use AN-8 hoses and fittings and 1/2" fuel lines for the supply side of the system. Where the 8-AN hose attached to the frame, we convert over to a 1/2" aluminum fuel line and it runs up the passenger side of the frame rail to the Fuel Filter. There we use a Aeromotive Fuel Filter which is also supported by the passenger side frame rail, the 1/2" line goes into and out of the fuel filter and then continues on up the frame rail till it ends at the cowl. There a Bulkhead Fitting will change it over to a AN-8 hose and direct the fuel to the Fuel Regulator. The Regulator maintains a pre-set fuel pressure,which in our case is 44psi., and directs that pressurized fuel to the Fuel Rails where it then goes into the Fuel Injectors. This is the supply side of the fuel system.
RETURN
Our Return System starts at the Fuel Regulator. The UN-used portion of the fuel gets diverted to the by-pass side of the regulator, here it inters a AN-6 hose and goes back toward the fuel tank. It takes basically the same route back to the fuel tank the fuel took from it. The only real difference is the hoses are AN-6 and the hard lines are 3/8". This type of system is called a Return Type Fuel System, because it draws the maximum amount of fuel from the fuel tank, pressurizes it to the pre-set amount and then returns the UN-used portion of that fuel. This happens over and over, constantly re-circulating the fuel.
07-05-07 Up-Date
We had originally what'd to use 1/2" Aluminum line for the supply and 3/8" Aluminum line for the return side on our Project Cobra'33 fuel system. The parts were bought and ready to be installed when the right time came, UN-fortunately when the right time came along, the lines just didn't pan out. The section where we would transition from hard line to soft line was just so short, and the side of the inter frame rail where we would have to run the lines was just to cluttered to make it feasible and nice looking. The solution, to run all the lines in performance hose, not aluminum hard lines. This meant we probably had to eat several hundred dollars worth of materials, but in the end, it was the right answer.
The Fuel System is basically the same as before just without any hard lines.
SUPPLY SIDE:
Starting at the rear of the vehicle at the Fuel Tank, we used a AN-8 to 1/4" NPT Fitting to convert the fuel outlet to An-8 performance Hose. There we used a AN-8 Straight Fitting and about 30" of hose to wind it's way over to the first Bulk-Head Fitting. There we used a An-8 Bulk-Head Fitting, 1-An-8 Bulk-Head Nut, 1-Tab and 2-An-8 Straight Fittings. From there we ran the hose up along the frame side to the canister type Fuel Filter from Aeromotive. Here we installed another Bulk-Head Fitting, which took 2-An-8 Straight Fittings, 1-An-8 Bulk Head Fitting, 1-AN-8 Bulk-Head Nut and 1-Tab. Then a short section of An-8 hose (12") to connect to the inlet side of the Fuel Filter, using 1-An-8 Straight Fitting. From there we ran another short hose (12") from the Outlet side of the fuel filter to another Bulk-Head Fitting Mounted to the side of the frame rail, this took 2-An-8 straight Fittings 1-An-8 Bulk-Head Fitting, 1-An-8 Bulk-Head Nut, and 1-Tab. After the fuel filter, be continued up along the side of the frame to the final Bulk-Head Fitting which was located in the area of the Fire-Wall. These took 2-An-8 Straight Fittings, 1-An-8 Bulk-Head Fitting, 1-Bulk-Head Nut, 1-tab and roughly 24" of An-8 hose. From the last Bulk-Head Fitting the fuel hose runs up with the Firewall to the back of the engine and then around to the drivers side front of the engine, where the fuel Pressure Regulator is located. To get to the Regulator, it took 1-An-8 90° Fitting, 60" of AN-8 Performance Hose, 1-An-8 Straight Fitting and 1-an-8 to 3/8" Radius Pump Fitting. Once we were at the Aeromotive Fuel Pressure Regulator, the Supply Fuel System was almost finished. The fuel goes in the supply side of the Fuel Regulator and the Regulated Fuel exits the opposite side. From there, we had to run a hose back along the drivers side of the engine and around the back of the engine to the passenger side fuel rail. To get to this spot, we used 1-An-8 to 3/8" Radius Pump Fitting, 2-An-8 90° Fittings and 48" of An-8 Hose. While we were at the Fuel Pressure Regulator, we also installed a 1-1/2" glycerin filled fuel pressure Gauge on the outlet port of the Regulator. This will give us a Fuel pressure reading right at the Regulator.
Once at the passenger side Fuel Rail, our hose Tee's with one section going to the passenger side Fuel Rail and another hose feeding the drivers side Fuel Rail. This took 1-An-8 Swivel Tee Fitting, 2-An-8 Straight Fittings, 18" -An-8 Performance Hose, 2-An-8 to 3/8 Radius Pump Fittings. The Fuel Rails were Aeromotive. This completed the Supply section of our Fuel System.
RETURN SIDE:
Our return system starts at the Aeromotive Fuel Pressure Regulator, here any UN-used fuel is returned to the fuel tank. The fuel exits the bottom of the Fuel Regulator and run around and to the back of the engine, there it runs down and to the Bulk-Head Fitting on the side of the frame rail. To get there we installed 1-An-6 to 3/8" Radius Pump Fitting on the Fuel Regulator, 1-An-6 45° Fitting, 60"-An-6 Performance Hose and 1-AN-6 90° Fitting. From the Bulk-Head Fitting the Hose runs along the inside of the passenger side frame rail to a Bulk-Head Fitting located on the rear of the frame. This took 1-An-6 Bulk-Head Fitting,1-An-6 Bulk-Head Nut, 1-Tab, 8'-An-6 Performance Hose, 2-An-6 straight Fittings. Then from the Bulk-Head Fitting the hose runs to the Return Fitting on the Fuel Tank. This took 1-AN-6 Bulk-Head Fitting, 1-An-6 Bulk-Head Nut, 2-An-6 Straight Fittings, 1-Tab, 1-An-6 to 1/4" NPT Fitting.
FITTINGS & PARTS USED IN OUR FUEL SYSTEM:
The Fuel Tank, we had to modify it to fit the chassis with the Winters rear end.
This is our In-Tank Fuel Pump
Swivel-Tee Fitting, used on the fuel rail
Stainless Steel braided Performance Hose
90° Full Flow Fitting
Straight Full Flow Fitting
O-Ring Fittings also called Radius Pump Fittings
Straight Bulk-Head Fitting
Bulk-Head Nut
Tabs
Line of Fitting Cap
Liquid Filled Fuel Pressure Gauge
Aeromotive Fuel Injection Rails
Straight An to NPT Fitting
An Fitting to Barbed Fitting
Aluminum Hard Line
Aeromotive Canister Type Fuel Filter
Replacement Aeromotive Fuel Filter Element's
Assorted An Fittings, 45°, 90° and Straight
Electronic Fuel Injectors
This is the Bulk_Head Fittings at the rear of the frame.
Heres the Aeromotive Canister Type Fuel Filter. Make sure you observe the In and Out markings on the filter.
This is our Project Cobra'33 on the new Frame Jacks we made. In this stage we are fitting everything to the frame. Here the fuel system, oil system, Transmission cooling system, and most of the braking system are installed. Soon the body will be fitted to the frame!!!!