Fuel line routing through front fender well

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rmchrgr

Skate And Destroy
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For the last couple days, I have been agonizing over how to run the fuel line in my Duster. Every method I have come up with has some major flaw whether it's too close to something it shouldn't be, is diffricult to execute cleanly or may open a different can of worms.

Right now, the cleanest solution appears to be having a short piece of hose from the outer bulkhead through the back of the passenger-side front wheel well and then through the inner fender panel. Right angle hose ends will keep it fairly neat. I considered a hard line with gravel guard here but the tight bends and fittings would make it stick out even further than the hose. I am looking at spiral hose covers to protect the hose from road debris but have not found anything specific yet.

The woven hose in this pic is an older piece that just happened to have a 90º hose end on it so it was used to demonstrate the idea. I'd make a new line as described below with more robust Aeroquip -6 AN socketless hose.
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This is how it would come through the inner fender on the other side. From here it would route up the inner fender to the throttle body.
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Guess my question is whether it will be safe to have this small length of line running behind the tire like this. On a dedicated race car sure, but this car will be street driven. I don't have the suspension in yet so I held up the wheel and tire to estimate where it would sit. (15 x 3.5" wheel with a 26" tire) It might be pretty close on the back end on full lock but it's hard to tell accurately. This would be the easiest method to execute cleanly but again, the major flaw could be having the line get damaged by road debris.

The other consideration is snaking the line through the space between the bottom of the firewall and the frame rail. The drawback here is that the hose is exposed right where it's supposed to be protected (converter ring gear). I can bolt a length of 1/8" plate to the area to protect the hose but that seems cumbersome. Maybe not though?

May not need the coupler in the middle there, this is just for mockup.
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Right now, my inclination is to go through the fender well. What do you all think?

Thanks for any input.

- Greg
 
You could fabricate any number of guards, whether for heat or road rubble damage

IMHO the OEM tested many scenarios in how to rout the lines and chose the rout they did for a number of reasons. I'm sure one is protection during a crash.

I would run hard line from tank to pump (short flex hose at the junctions of course)

And if heat is a concern a simple tin shield can work wonders. Look at your catalytic converter.
 
This is what I did, ran outside the frame rail then came back in before the cross member. I opened up the existing hole to fit the lines and secured it on both sides then through the pipe.

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No way id run my fuel line on the outward side of the frame rails. You get hit theyget cut. Jmo
 
OK, to be clear - from the rear to the front is already hard line with gravel guard. From the tank it runs along the inside of the wheel arch and up the frame connector to the trans cross member. That part is done. I am only concerned with the area next to the transmission bellhousing and how to get the fuel line around it and back into the engine bay forward of the firewall.

Previously, the fuel line did run along the inner frame into the engine bay like the factory routing. At that point, the car went 12.0 @ 110. After 8 years of re-doing the car, it should be somewhat faster requiring stricter adherence to safety. Hence the change in routing.

So, the face of the bell is about 22" forward of the cross member. Right before the trans cross member, I can run the line to the outside of the frame connector and through the outboard bulkheads. The question is this; whether that short piece of flex hose in the front wheel well will be OK on the street (I'm thinking most likely it will be) or, do I run the line through the space between the firewall and frame rail where I'd still probably need to put some sort of big, heavy protective shield around it to protect it from a potential trans explosion.
 
OK, to be clear - from the rear to the front is already hard line with gravel guard. From the tank it runs along the inside of the wheel arch and up the frame connector to the trans cross member. That part is done. I am only concerned with the area next to the transmission bellhousing and how to get the fuel line around it and back into the engine bay forward of the firewall.

Previously, the fuel line did run along the inner frame into the engine bay like the factory routing. At that point, the car went 12.0 @ 110. After 8 years of re-doing the car, it should be somewhat faster requiring stricter adherence to safety. Hence the change in routing.

So, the face of the bell is about 22" forward of the cross member. Right before the trans cross member, I can run the line to the outside of the frame connector and through the outboard bulkheads. The question is this; whether that short piece of flex hose in the front wheel well will be OK on the street (I'm thinking most likely it will be) or, do I run the line through the space between the firewall and frame rail where I'd still probably need to put some sort of big, heavy protective shield around it to protect it from a potential trans explosion.
I ran the pipe between the frame rail and bell-housing to encase the fuel lines for protection per NHRA rules.
 
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Mine comes in through the inner fender well with a bulkhead fitting down low with a #12 up to my fuel log with the regulators. Hard to see where in the picture though.

IMG9505711.jpg
 
Mine comes in through the inner fender well with a bulkhead fitting down low with a #12 up to my fuel log with the regulators. Hard to see where in the picture though.
I can sorta make it out towards the front. Presuming you drive it on the street? What kind of hose?
 
Yes, it's driven on the street. It's a Fragola brand hoes and ends. Most of the car is all Fragola.
 
Thanks. Guessing there are no concerns with having the lines down low in the front wheel well or they wouldn't be there. I'm really leaning towards that method because of the way it would come in to the engine bay. If your line comes through in the front you have a much longer length than I'd have anyway.
 
Thanks. Guessing there are no concerns with having the lines down low in the front wheel well or they wouldn't be there. I'm really leaning towards that method because of the way it would come in to the engine bay. If your line comes through in the front you have a much longer length than I'd have anyway.
Not with the fuel pump I have. Good to 3000 H.P.

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FWIW....here's what I did on the avatar car.

I ran 3/8" NiCu hard line inside the frame rail from my elec pump, through the trans cross member, then in the RF wheelwell for just a bit. It turns upward and enters the bottom of the regulator that is mounted on the "horizontal" part of the inner fender. The regulator then sends a small line to the cowl-mounted fuel pressure gauge along/under the firewall seam and the main fuel feed line to the rear of the carb to its dual inlet. You can see the regulator in this pic and the carb feed line in the 2nd pic. This minimizes heat in the fuel line and so far, I have not needed a cool can on the car.
As for the bit of line exposed in the wheelwell, it's tight to the body line and can be covered with some wire loom or Kevlar loom as needed. I have not done that as this car doesn't get out on dirt roads or in bad weather!!

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I'm getting ready to run lines on my '66 Dart, so I'll be curious what you end up doing. My only advice is to try to minimize the number of fittings. They're costly and just add another potential leak point.

Keep us posted on what you decide!
 
I'm getting ready to run lines on my '66 Dart, so I'll be curious what you end up doing. My only advice is to try to minimize the number of fittings. They're costly and just add another potential leak point.

Keep us posted on what you decide!
I have so many fittings...

AN fittings and hose ends are a worthwhile investment because work really well. Really have not had many if any leak on me over the years. They are generally reusable too.
 
The other consideration is snaking the line through the space between the bottom of the firewall and the frame rail.
This is what I did.
PTFE braided line from the filter/regulator mounted on the frame rail near the tank, through the crossmember, up to the top of the inner fender.
1 line, no kinks, rubber grommets in the crossmember, rubber hose and velcro heat wrap over the line as it snakes through the firewall/frame rail area.
 
After looking at this 19 ways to Sunday, this is what I came up with.
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Unfortunately, this particular line is too short so I will have to make another one. Only needs another inch or so no big deal. There needs to be a little more give in it. It's pretty far out of the way here and fairly short. It works.

I did drill another hole in the outboard bulkhead to get the fitting closer to the frame rail. Relocating that hole also helped with routing the line behind it. The hole to the left put the fitting too close to the floor and only a right angle fitting coming off the bulkhead would fit putting a severe angle on the hose. Where it is now allows use of a straight or 45º hose end which relieves the tension.

Initially, I looked at running it like below but decided against it for now.
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I will say it does tuck in pretty nicely there. The main drawback to this method is having to drill another 1/2" hole right in the middle of the inner fender. Plus, there is more chance of debris hitting it since there is more surface area to it. Also, where the bulkhead comes through the panel now is much less conspicuous. In fact, there is a hole that's the same size and in the exact same spot on the driver's side so it looks like it's supposed to be there.

Here is how it will enter the engine bay. The line will go up over the top of the shock tower and across to the engine away from exploding transmissions or heat. I can use the factory holes in the panel for line clamps so it won't be just hanging there like it is now.
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I've literally been agonizing over this for years, glad to finally get over that stupid hump. Thanks for the suggestions.
 
I would build a stone shield with a lot of open space between the shield and the body to allow dirt and crud out.
 
I would build a stone shield with a lot of open space between the shield and the body to allow dirt and crud out.
OK, how would you go about that?

I thought heavy, clear plastic tubing over the hose would work for extra protection.
 
OK, how would you go about that?

I thought heavy, clear plastic tubing over the hose would work for extra protection
The fittings are vulnerable


Cut and shape a piece of 18g steel and fit it into the area so the hose and fittings has some protection
 
Rmcharger you do nice work, but I just don’t know if I like that chosen path.
Thanks. I'm really not sure how else to do it. From the outer bulkhead you have two choices - through the wheel well or in the space between the firewall and frame - I chose the wheel well. Frankly, I don't want to get involved with making a shield on top of the inner fender, it just seems clunky. The way it is now is obviously not perfect but no method is.

Don't get me wrong, I'm not being defensive but I am being serious when I say I've been going back and forth about this for years. It wasn't an easy or snap decision to put the line there, trust me. I literally stared at it for days trying to think of an elegant solution - there isn't one. There had to be a choice made to move the project forward.

I looked at your thread, it's basically the same as what I'm doing by running the line through the outer bulkhead. You didn't show any pics of how you got the line into the engine compartment though. How did you accomplish that?
 
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