Fuel line: hard vs rubber

Ok, so not really a "performance" question per se, but I'm curious. Right now I'm running rubber from the mechanical pump to the carb. It's a 2bbl Holley with the fuel bowl oriented away from the VC.

What is the safest of the 2 options?

Also, how do you feel about having a fuel pressure gauge permanently set up in the engine bay? If OK, what set up do you recommend?

Cheers!

As long as you route it sensibly away from extreme heat and check your rubber fuel lines for cracks periodically, rubber should be fine.
I usually end up running rubber until I get things working correctly and then bend a final permanent steel line.

I run a fuel pressure gauge all the time. It's mounted on the boss where the front engine lift hook bolts. I built a bracket for it. You can find a post on here somewhere where I got recommendations as to what brand to get. Some leak gas when they fail, so you want to avoid those brands.

Hi, X2. Plenty of cars use the rubber line from the pump to the carb. The hose can certainly handle the job. Smart to be careful in routing to avoid heat, sharp bends, and chafing. By the way you can see my home made steel fuel line, clamped to the block, in my little picture. Good luck

There is a reason most racing venues only allow a few inches of rubber hose.

i prefer to run as little rubber fuel line as possible. steel line very rarely splits open under high pressure with age, and if when first installed an no leaks, rarely leaks after it ages. the downside to steel line is that making bends is tougher.

as much steel as possible
there is a $4.00 tool for bending the 3 or 4 angles U need
looks good too, esp if painted or buffed & clear coated !

I run steel lines from the fuel pump to the regulator steel to pressure gauge then adapt to AN steel braided line to the fuel filter.

forgot to mention, a fuel pressure gauge is a great addition under the hood. makes for a nice tuning tool as needed. and no need to try and find one in the tool box. so go ahead and permanently mount on in the engine compartment.

You have that ethanol issue with rubber. The alcohol eats away many kinds of rubber and plastic. Make sure you use a rated FUEL LINE hose if you do go with rubber. I used metal all the way.

Thanks! I'll use the rubber for now until I get the steel line all set up. I'll also invest in a regulator and gauge to mount under the hood. Is it best to have the regulator as close as possible to the carb? Also, I'm not a fluids guy so are there any bends I should avoid? Obviously will avoid sharp turns so that I don't kink/split the tube. But anything that a noob should avoid?

cr_bobcat":dennn9uo said:

Thanks! I'll use the rubber for now until I get the steel line all set up. I'll also invest in a regulator and gauge to mount under the hood. Is it best to have the regulator as close as possible to the carb? Also, I'm not a fluids guy so are there any bends I should avoid? Obviously will avoid sharp turns so that I don't kink/split the tube. But anything that a noob should avoid?

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the closer to the carb you can get the gauge, the more accurate it will be. you want to know what the pressure is at the carb.

when bending steel tubing, you want bends that are not too tight, but as long as you dont kink the tube, you can do pigtail bends if you want.

Steel is the way to go for safety, most auto parts stores stock different lengths and sizes. Fan/water pump V belt pulley works good for bending if you don't have a tubing bender.

"Steel is the way to go…"
or if U want there's a nice product NiCoFe (I think it is) that's a lill newer (expensive) but very less prone to rust, more malleable, and lighter.
Comes in coils just like the metal break & fuel lines. I've not seen it in the straight, flared & fitting produced 4 or 5 ft sections prts houses have for break line.
Good reason to buy a new tool - get a $20 flair tool & use that nice line the whole way,
?AN fittings from XRP? (on the web)…

Something else that works well for bending tubing if you don`t have a bender.I have used sockets,wood dowels,hammer handles and ect.Just take your time and go slow.
Good luck.Have fun.Be safe.
Leo