1:5 FUEL SYSTEMS
Location: All fuel tanks, lines, pumps, valves, etc. must be outside
of the driver’s compartment and within the confines of the frame
and/or steel body. Cool cans, fuel-distribution blocks, etc. must be
located at least 6 inches forward of the flywheel/bellhousing area on
rear-wheel-drive (RWD) vehicles, and on opposite side of
flywheel/housing area on front-wheel-drive (FWD) vehicles. Fuel
pressure gauge isolators, with steel braided line, may be mounted
on firewall.
Tanks: When permitted by class regulations, fuel tanks located
outside body and/or frame must be enclosed in a steel tube frame
constructed of minimum 1 1/4-inch O.D. x .058 chromoly or .118
mild steel tubing. All fuel tanks must be isolated from the driver’s
compartment by a firewall, completely sealed to prevent any fuel
from entering the driver’s compartment. All fuel tanks must have a
pressure cap and be vented outside of body. A positive-locking
screw-on fuel tank cap is mandatory on all open-bodied cars.
Insulated fuel tanks prohibited. When used, fuel cells must have a
metal box protecting the part of the fuel cell that is outside of body
lines or trunk floor, excluding hose connection area in rear. Nonmetallic fuel cells or tanks must be grounded to frame.*
Lines: All non-OEM fuel lines (including gauge and/or data
recorder lines) must be metallic, steel braided, or NHRA-accepted
“woven or woven-pushlock.” A maximum of 12 inches total (front to
rear) of non-metallic or non-steel braided hose is permitted for
connection purposes only; individual injector nozzle and motorcycle
fuel lines are excluded. Fuel lines (except steel braided lines) in the
flywheel/bellhousing area must be enclosed in a 16-inch length of
steel tubing, 1/8-inch-minimum wall thickness, securely mounted as
a protection against fuel-line rupture. Fuel lines may not be routed
in the driveshaft tunnel. It is mandatory that fuel lines passing
supercharger drive belts be steel braided, NHRA-accepted woven
or woven-pushlock, or be enclosed in protective steel tubing. A
current list of NHRA-accepted woven or woven-pushlock fuel lines
is available on*NHRA.com. All NHRA-accepted fuel lines must use
ends that are specifically designed for the type of fuel line being
used. No hose clamps allowed on NHRA-accepted fuel lines.
Pumps/Valves: Cars with non-OEM-type mechanical fuel pumps
must have a quick-action fuel-shutoff valve within easy reach of
driver and located in the main fuel line between the fuel tank and
the carburetor and/or injectors. Fuel recirculation systems not part
of normal fuel/pump system prohibited. All cars in Stock, Super
Stock, Competition, and Pro Stock must be equipped with a
positive-lock drain valve located between the fuel tank and the
carburetor(s) or fuel injector to facilitate removal of fuel samples for
fuel-check purposes.