The Bottom Line:
Line Sizes: Choose -8 feed and return for dual pumps systems. We recommend -10 feed / -8 return for triple pump systems.
Line Types: Startlite will emit fuel smell and should only be used on cars kept outside or in detached garages/shops. Cars kept in attached garages should use FlexLP or PTFE, which will not emit a fuel smell. PTFE has a stainless outer reinforcement and will last forever, whereas FlexLP has a soft black/gray nylon outer braid and some insulating properties. (no NVH and more friendly with fuel pressure sensors/gauges)
If you want to know more detail, please read on:
Fuel Line Sizes
Fuel Line Size for Dual Pump Systems
We suggest -8 feed and return in any dual pump setup, simply because there is no measurable benefit to running a -10 feed with any dual pump fuel system. However, selecting a -10 feed is a good choice if you're planning to possibly upgrade to a triple pump system later (via our triple pump upgrade program). Of course, it is possible to run a -8 feed and -6 return; however, most of our customers find the fuel system installation is more flexible when all the fittings are the same size.
Fuel Line Size for Triple Pump Systems
-10 feed and -8 return lines allow any triple pump system to operate without restriction. However, -8 feed/return may be used if you're running three small fuel pumps (i.e. GSS342) or if your fuel system choice was marginal over whether to choose a dual or triple setup. So, if you're making 1100 rwhp on E85 (which is possible on a dual pump setup if your build is very efficient) but you chose to go with a triple pump setup, we would suggest a -8 feed/return since you don't need every ounce of performance out of a triple pump setup.
Fuel Line Types
We do not recommend any push-on style hose for fuel. (even the stuff we carry) The barb on push-on hose ends stretches the fuel hose in the direction of failure. Even securing the hose with a hose clamp will not prevent failure, since it does not change the simple fact that the hose is stretched out at the tip of the barb. (failure point) However, push on style hose and fittings are a good low cost alternative for use with lubrication and coolant lines.
FlexLP
FlexLP has the best ratio of pros vs cons than our other hose offerings. Most importantly, it's low permeability prevents fuel vapor smell when the vehicle is parked in closed areas. Cosmetically, some of our customers prefer the black outer braid over the stainless braid of PTFE.
ADVANTAGES
- Compatible with all automotive fuels, lubricants, and coolant
- Low permeable = no smell when vehicle parked in enclosed locations
- Fast to assemble and install
- Will not contribute to NVH (noise vibration, harshness)
- Soft outer braid will not damage contacted surfaces
DISADVANTAGES
- Expect 5-7 year life
- Requires cable cutter to cut (has internal stainless reinforcement)
PTFE
PTFE is the most resilient to heat and chemicals than any other fuel line we offer, and likewise can be expected to outlast the vehicle. The PTFE core cannot be permeated by any fuel, and therefore will not emit a fuel smell when the vehicle is parked in closed areas. Cosmetically, some of our customers prefer the look (or contrast) of the stainless outer braid.
ADVANTAGES
- Compatible with all automotive fuels, lubricants, and coolant
- Infinite shelf and service life
- Non-permeable = no smell when vehicle parked in enclosed locations
- Small outer diameter for AN size = small bend radius, light weight
DISADVANTAGES
- May contribute to NVH (Noise, Vibration, Harshness)
- Stainless braid may damage contacted surfaces
- Expect longer installation times
Startlite
Startlite is race hose, and therefore we only recommend it for vehicles that are stored outside or kept in a detached garage or shop. Fuel can permeate the lines and will usually emit a fuel smell in the storage area.
ADVANTAGES
- Compatible with all automotive fuels, lubricants, and coolant
- Easy to cut, fast to assemble and install
- Will not contribute to NVH (noise vibration, harshness)
- Soft outer braid will not damage contacted surfaces
DISADVANTAGES
- Permeable = expect fuel smell smell when vehicle is parked in enclosed locations
- Expect 5-7 year life