TLOWE,,,,

Only one year that I know of GM gapped there plugs @ .050,,, 1975.First year of HEI,, IIRC?

Then they stopped that the following year because they were having a hard time passing smog tests w/a .050 plug gap.

I still run a .040 gap & run up to 21 psi of boost pressure w/an Aquamist alky injection,,, but I also have an MSD 6A box.

My 65 SS Malibu weighed 3420
It had disc brakes,Rally steel wheels,1.250" front sway bar.

I put a 350 SBC & a turbo 350 trans.
Also had A/C.

I will guess yours will weigh 3200 - 3300 LBS
What do you think it weighs?

MBHD

12 port SDS EFI