Best route for fuel line to mechanical pump. MK4 with 302 SBF

[Rotorcraft]

Looking for advise / photos for the best way to route the fuel lines in the engine compartment to the mechanical in block fuel pump. SBF 302 350+ HP .

I want to make sure I don't put it anywhere I shouldn't.

Input on type of fuel lines welcome too!

Thanks

Jeff

[Blue MK3]

Here's a couple of poor quality photos of my layout. Supply line from tank is steel along the DS main frame tube (blurry). About even with the pump, it changes over to a rubber line and goes to the pump inlet. The output line is steel braided (Summit) and goes to a pressure regulator mounted on the panel, then up and in front of the distributor and coil and on the the carb.DSC_0152.JPGDSC_0156.JPG

[edwardb]

I've done SBF's with mechanical fuel pumps on both of my builds. Used the 5/16 supplied steel lines for the Mk3. They would be fine for your 302 as well. Went to 3/8 inch rigid stainless for my Mk4 build. I'm happy with it, although takes the right material and the right tools. Then it's really not that hard. Routing was similar for each. Pictures from my Mk4 build thread:

Outside the 4 inch tube to right across from the fuel pump. Used stainless steel braid from there to the pump.


Down the 4 inch tubes to the back: (rear brake line here as well)


Up and over the rear axle. I used a union here. The only one.


Across the 2 inch square tube in back, and down to the tank. Your routing could be different in this area depending on rear suspension.


Stainless steel braid to the tank:


Couple other comments. Personally, I would stay with rigid lines, either steel or stainless. See guys do whole cars in stainless steel braid. Not only is it expensive, if you don't use the right material you're eventually going to get odor and possibly worse. Even the right material can be problematic. If you go to a larger fuel line (e.g. 3/8 inch) you will need to use a larger pickup in the tank. The supplied FFR one is 5/16. Breeze sells a nice 3/8 unit. Finally, note no fuel filters in my line. Lots of debate on this one, but generally it's recommended to have a sock on the pickup (normal) and a filter between the pump and carb, e.g at the engine. For a mechanical system, you want to push the fuel though a filter not pull it. Good luck.

[Rotorcraft]

Thanks you guys !

[mcwho]

I've done SBF's with mechanical fuel pumps on both of my builds. Used the 5/16 supplied steel lines for the Mk3. They would be fine for your 302 as well. Went to 3/8 inch rigid stainless for my Mk4 build. I'm happy with it, although takes the right material and the right tools. Then it's really not that hard. Routing was similar for each. Pictures from my Mk4 build thread:

Outside the 4 inch tube to right across from the fuel pump. Used stainless steel braid from there to the pump.


Down the 4 inch tubes to the back: (rear brake line here as well)


Up and over the rear axle. I used a union here. The only one.


Across the 2 inch square tube in back, and down to the tank. Your routing could be different in this area depending on rear suspension.


Stainless steel braid to the tank:


Couple other comments. Personally, I would stay with rigid lines, either steel or stainless. See guys do whole cars in stainless steel braid. Not only is it expensive, if you don't use the right material you're eventually going to get odor and possibly worse. Even the right material can be problematic. If you go to a larger fuel line (e.g. 3/8 inch) you will need to use a larger pickup in the tank. The supplied FFR one is 5/16. Breeze sells a nice 3/8 unit. Finally, note no fuel filters in my line. Lots of debate on this one, but generally it's recommended to have a sock on the pickup (normal) and a filter between the pump and carb, e.g at the engine. For a mechanical system, you want to push the fuel though a filter not pull it. Good luck.

EDwardB,
What kind of bending tool are you using? I have the 5/16 copper/nickel fuel line and also the copper/nickel brake line. Not haveing much luck making nice clean bends. The brake line is doable but the fuel line is a bear. Tried using a cheap tube bender, no luck there. I have a 302 based engine with Mech fuel pump, want to run along ds 4" rail like you did. I have IRS so i was thinking down and up the X frama member in front of the fuel tank. I think 1 union will help and was thinking about just above where the lines come up from the 4" rail in the rear behind the drivers seat.

[edwardb]

EDwardB, What kind of bending tool are you using? I have the 5/16 copper/nickel fuel line and also the copper/nickel brake line. Not haveing much luck making nice clean bends. The brake line is doable but the fuel line is a bear. Tried using a cheap tube bender, no luck there. I have a 302 based engine with Mech fuel pump, want to run along ds 4" rail like you did. I have IRS so i was thinking down and up the X frama member in front of the fuel tank. I think 1 union will help and was thinking about just above where the lines come up from the 4" rail in the rear behind the drivers seat.

The fuel and brake lines in the build were all bent using the pictured bending tools. The tubing bender and forming pliers are from Eastwood. http://www.eastwood.com/tubing-bende...liers-kit.html The smaller tubing bender is for brake lines only and was purchased locally (for me) at InLine Tube. It was able to do much smaller radius bends on the brake line material than the Eastood tubing bender purchased. The forming pliers I found to be pretty useless, frankly. Put marks in the SS tubing and really didn't help much. I barely used it.

For the fuel line itself, I had zero issues making clean bends. Certainly no issues with it crimping or collapsing, it that's the problem you're having. My biggest issue was the 3/8 SS tubing is just plan stiff. It was about all my office hardened body could do to start some of the bends. If I do it again, may try to find a bender with longer handles. My original idea was to complete the fuel line in once piece as well. I also was at the chassis only stage (no sheet metal) so everything was wide open. I quickly realized that even if I could bend it exactly right (which wouldn't have high odds...) I wouldn't be able to snake it into the chassis, through all the necessary openings, etc. I ended up with the one union pictured previously. To get all the bends exactly right, I bought a roll of soft copper tubing at Home Depot. I think it was around $15 for a 10 foot roll. I used this to make exact patterns of each piece, then duplicated in the SS. Took some practice to learn exactly where to place the tubing in the bender to have the bend at the right location. But once I figured that out, was able to duplicate the pieces exactly. I'm a big fan of the SS tubing. With the right material and tools, it can turn out great. Will easily last the life of the vehicle. Hope this helps.