DrEvil11417

On an '86 TPI car... i'm going to carb so I need to switch from whatever metric? size lines that are on the car to the 3/8" fitting on the reglator

rodj

Russell and others make a metric O ring to -6AN fitting that allows you to connect the supply line at the fuel filter direct to the carb using -6 (3/8) braided line.
Russell part # 648060 (16mm x 1.5)

If using a bypass type regulator and the stock return line to tank also need fitting to connect -6 braided line to stock return coupling by fuel filter.
Early models had 14mm return at fuel rail; not sure of size at coupling
# 640860 (14mm x1.5)

Aggravated4life

Yeah the 86 cars had a smaller return line size.The 88 and up cars I believe were both 3/8 feed and return.
I forget the exact size but letting you know I agree with what I quoted,there was a smaller line for return on earlier cars.

Slalom4me

Earls also offers hardware that can help adapt aftermarket fuel lines
to the OEM fuel lines.

Here is what the female fittings on the OEM fuel rail look like at the
front of the engine where they join the supply/return lines that feed
from the tank.



The following illustration shows parts for the earlier supply and return
lines. For the later cars, on the supply side substitute a 16mm to -6 AN
(9894DBJERL) in place of the 14mm to -6 AN shown here (same fitting
is used for supply/return on later cars.)



The fittings shown on the right side of the image are specific to the
HSR project - substitute -6 AN hose ends that are appropriate for
the components you need to connect to.

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