gschaerer

My wife and I own a restored '66 SB 350 HP, 4 sp convertible, no power brakes/steering/air conditioning. As part of the total engibe rebuild, the rebuilder/assembler installed a 13 lb after market pressure cap which we want to replace with a correct looking and proper functional cap.

In researching our original owners manual, chassis/service manuals, Roland Adams book etc, 13# seems to be specified. We are confused as to whether this is the correct pressure. Several forum vendors advertise a correct pressure cap for this car as 15#. Which is correct?

Please help us out with what is the correct pressure cap we need. All advise is greatly appreciated.

George and Sue Ann Schaerer
Fairfax, VA

avideo

and I've always used a 15 or 16 lb. cap on the surge tank. Never any issues.

Powershift

George:

The NCRS Judging Manual calls for a #RC307 for 1965 without air conditioning, and a #RC26 for all 1967 with and without air conditioning. Unfortunately, I do not have a 1966 Judging Manual.

Generally 1966 and 1967 Corvettes are very similar and I would EXPECT a 1966 small block without air to take the #RC26. Long Island Corvette Supply also shows this in their latest catalog.

Let's see if any 1966 SB owners reply. Otherwise I would buy a #RC26 from Long Island. Their repro is considered the best or certainly one of the best available. I have an older #RC26 from Paragon, and you can clearly see the differences between it and an original. I plan to purchase one from Long Island soon.

Larry

EDIT: The #307 is a 13 psi cap for aluminum radiators and the #26 is a 15 psi cap for aluminum radiators. Should have stated this above.

stingrayl76

Not familiar with "Roland Adams", however "Noland Adams" reference shows the RC26 15# cap for all 1966 Corvettes with base (327) engines.

gschaerer

Thanks to all for clearing up the confusion. Apologies to NOLAND ADAMS, did not mean to mispell the name. Old age and lack of typing skills. Bad eyesight when looking on the keyboard also.

George and Sue Ann

1Sweet66

George,
My NCRS 1966 Technical Information Manual and Judging Guide, 4th edition, lists under Chassis Section, section 5 Engine Cooling System, Expansion Tank or Radiator Cap-
Small block tanks use AC model RC-26 rated at 15 psi
Big Block radiators use AC model RC-15 rated at 15 psi

Hope this helps.