74ZZ430

I'm adding a nitrous kit and need to incorporate a fuel pressure saftey switch, a in line filter and a tee fitting all between the mechaical fuel pump and the carb. Fuel preesure should be no more than 8 psi. Is there any reason I shouldn't use a compresion fitting( 3/8 pipe to 3/8 tube) off the bottom of the fuel pump if it works out better going that way. I've seen compression fittings used in hydraulic systems running up to 1000 psi. Any information would be appreciated.

comp

i ve done it but it ain't the right way... gas is so much thiner(don't remember
the correct term) it can seep,wick, what ever you want to call it easyer than
oils is it a copper compression on the steel line??? if so it will work

Big Fish

You can get hydraulic compression fittings anywhere hydraulic hoses are made. These fittings are much more substantial then "plumbing" compression fittings. I wouldn't be afraid to use them. They are normally steel (not brass) and use 2 compression sleeves.

norvalwilhelm

I have used them in fuel lines before without a problem. My 1/2 inch stainless main line has one stainless compression fitting in it and it has never leaked even after taking it apart many times.

markdtn

I have them in 2 different TPI conversions with no problems.

joe73vette

I used compression fittings for the tripower carbs on my firebird because of the close quarters, but if you learn to make flares, it's a skill you'll keep for future projects. Plus it's an excuse to buy another tool! Joe


[Modified by joe73vette, 6:58 PM 12/18/2003]

BSeery

My fuel injection system uses compression fittings when going from hard line to hose. I go from aluminum tubing to a -06 fitting, then from there to -06 hose to the next fitting.

It holds up to 40 psi. I had one leak. Just tightened up the fitting and the leak is gone.

BazMan20

I get compression fittings here any they've always worked fine. I wouldn't be afraid at all to use compression fittings with gas, just make sure they installed correctly - aka DON'T!! over tighten them. I hear all the time about people who tighten their compression fittings to death and then wonder why they're leaking. If you wanted to be extra-safe with this application, I would think about finding some compression fittings with rubber or nitrile ferrules (compression sleeves) instead of metal ferrules. Those might more impervious to improper installation.

71VetteLover

I have used brass compression fittings for fuel lines for 50 years without any problems.

zwede

I've had a few compression fittings on my EFI system (43 PSI) for 20 years and no leaks.

CheezMoe

I've always been taught that you don't **** around with the pressure side and always use hardlines and flared fittings, so thats what I do. ymmv! Flaring is getting to be a lost skill . I thoroughly enjoyed learning it via my own projects.

7T1vette

Fuel pressure for carbureted cars is low (under 10 psi) and [metal]compression fittings have WAY more capability for holding pressure than that. Any metal comp fitting is very capable for sealing EFI pump pressures, too.

I would NOT use a polymer seal or synthetic rubber seal compression fitting with fuel.