Will fuel boil if lines are too close to headers?

[Stang_ROTY]

I have a safety related question here. Since I've switched to longtubes my fuel lines for the external tank pump (which are steel braided) are VERY close to me headers. The closer of the two lines is the return line and it's about 1/2" away from the header. The send line is about 1" away.

Is this dangerous? I understand that if there was a leak a fire could start really easy but without a leak am I at risk for boiling the fuel , especially when the car is shut down and restarted? At what temps will fuel boil and what happens internally when the boiling fuel reaches the injectors?

[Nixon1]

I don't know a lot about this kinda thing, but I would definitely say that's a very very very bad idea. The fuel lines don't seem to be very thick or insulated...and header temperatures are HIGH. The air within the first inch around hot headers is probably well over 500 degrees I'd say. If the fuel gets too hot...well I don't know what would happen...I'd think the injectors would have a hell of a time shooting it out. And the power would SUCK.... Fuel works in the same kind of way air does...the cooler the better. Not to mention how dangerous it is having the lines that close to the headers....if that fuel superheats, well, who knows...it could even try to detonate. Move the lines!!

[Stang_ROTY]

I agree that it's potentially a disaster waiting to happen but I don't know where else they can go? The only other thing would be to tie them above the tranny I guess in that valleyand have them come out by the firewall instead of over by the pass side of the firewall

[PKRWUD]

I'd move them. You really are just asking for trouble, and heated fuel never made anybody go faster.

As far as fuel boiling, or creating a vapor lock condition, I think you'll be okay. It's really hard to do that in a pressurized fuel system. When your pump is pulling the fuel, like a stock mechanical pump, it creates a vacuum in the line, which is very susceptable to vapor lock. But when the pump is pushing from the back, it creates high pressure in the line, which is tough to vapor lock. None the less, I'd put moving the fuel lines very high up on my priority list if I were you.



Take care,
~Chris

[WADS56]

You have to move them anyway. I am not sure but i think that NHRA rules are that they have to be mounted on the outer frame rails and can only enter threw the side of the engine compartment. This could all be bull because i read it off the internet but it does make sence.

I have mine ran that way and it keeps them away from the exhaust and any moving parts. I have a aeromotive pump that feeds a -10 line all the way down the car on the outside of the frame conecters. It then enters in the engine compartment just behind the strut tower where the Aeromotive regulater is. The return line runs next to the feed line. It makes a nice clean and safe install.

[Stang_ROTY]

THat sounds pretty nice and clean. Do you have any pics you can post? I have them going through the subframes and then coming up to the bay next to the exhaust. Your way sound much better and SAFER. I don't think that fuel could boil while runningb/c it flows so fast but when I shut her off to say, go into a store, then come back out within 5 minutes it might be getting hot next to those headers.

The funny thing is that my headers cool off in like 5 minutes..literally. They don't stay hot for very long. Must be that HTC coating

Originally posted by WADS56
You have to move them anyway. I am not sure but i think that NHRA rules are that they have to be mounted on the outer frame rails and can only enter threw the side of the engine compartment. This could all be bull because i read it off the internet but it does make sence.

I have mine ran that way and it keeps them away from the exhaust and any moving parts. I have a aeromotive pump that feeds a -10 line all the way down the car on the outside of the frame conecters. It then enters in the engine compartment just behind the strut tower where the Aeromotive regulater is. The return line runs next to the feed line. It makes a nice clean and safe install.

[Nixon1]

Are those headers cast iron or something else? If they're cast iron...jesus...I have to figure out what that coating is! My headers stay hot for HOURS.

[Stang_ROTY]

Honestly,

I don't know what material the headers are. They seems much more thin than the BBK' I pulled off. THey are the MAC brand, longtubes for the 351 swap w/HTC coating. I'm sure the coating helps a bit.

[Roscoe]

I just finished installing my fuel lines yesterday. I'm nowhere close to the header, I guess it depends on where you have your FPR mounted.

I have the same config that WADS56 has.

[Stang_ROTY]

So are you guys taking them from the subframes and running it to the inside of the fender and then back through the strut tower area or am I misunderstanding?

Thx for the help guys!

[Roscoe]

Originally posted by Stang_ROTY
So are you guys taking them from the subframes and running it to the inside of the fender and then back through the strut tower area or am I misunderstanding?

Thx for the help guys!

I'll go snap a few pics.....

[Roscoe]

Here they are in order from front to back. That first sharp bend to go under the car is a tricky one! The closest they are to any heat is 3" away at the tailpipe. The fenderwell pieces are taken out. Once you install them after this, you won't be able to see anything.

[Stang_ROTY]

Roscoe,

Good lookin!!

Thanks very much...you read my mind. I was going to ask you for those. Man, I need to get me a digital camera :-)

[WADS56]

Mine looks like that to. here is where i put the fpr

[WADS56]

oops here it is. it's the #6 pic.


http://forums.mustangworks.com/showt...threadid=35003

[Roscoe]

Originally posted by WADS56
oops here it is. it's the #6 pic.


http://forums.mustangworks.com/showt...threadid=35003

I love your MSD set up!!!

I put my FPR in front of the motor with the lines running back for one reason.......

When you launch or accelerate very quickly, gravity wants to push your fuel back. Rather than have it run away from the motor, I want as much as possible to run into it.

[WADS56]

Originally posted by Roscoe
I love your MSD set up!!!

I put my FPR in front of the motor with the lines running back for one reason.......

When you launch or accelerate very quickly, gravity wants to push your fuel back. Rather than have it run away from the motor, I want as much as possible to run into it.

I see what you are saying but if it is under pressure it shouldn't matter because liquid will not compress so it can't go anywhere. Even if it does though I run a carb and there is plenty in the fuel bowls to make up for any issues.