3841645
General Motors Part # 3841645 Brake Pedal Return Spring
Extension

Copy
Pictures are from an exact reproduction part.
This part is used on non power brake equipped
models.

Holes
The large hole is goes around the master cylinder
clevis pin at the brake pedal. The small hole is
where the brake pedal return spring is attached.
This part is usually mated with part # 3850084
Construction
This part is made from spring steel.
Overall length is about 1 9/16".
Large hole is about 3/8".
Small hole is about 3/16".
Applications
3841645
4.827 EXTENSION, Brake Pull Back
64-66 Chevelle
70-72 Chevelle
67 Camaro
68-72 Chevy II
73-74 Nova (exc. P.B.)
73-75 ALL X (exc. J50, JL2) (Olds Parts Book)
Disclaimer:
Factory correct applications are your responsibility. GM made part and part # changes with no rhyme but a reason (no production interruptions at any cost).
Application charts are for replacement parts that were available at the time of parts book printing, and when possible model specific assembly manuals.
My observations come from the parts I have in my collection or other reliable sources your parts may differ.
If Factory correctness is your goal, do more research, join car clubs,
forums and buy an assembly manual if one is available for your Project Car (you wont be sorry).
This is a fun and interesting part of the hobby!