<VV> A/C Update - 66 Monza

[Bill H.]

                                                                                 B"H
 
Hi all..hope all you in Heat Wave Land are staying cool!
 
Anyway, I completed the repairs on the A/C in my 66 Monza Sport Sedan.  I charged the system with Freon, connected the belt, and added dual cooling fans to the condenser and a PrestoLite idle-up solenoid, along with a relay to control these accessories plus the compressor clutch.
 
The system blows nice and cool, but after driving in heavy city traffic for about 30 minutes, the engine starts to ping loudly and I know I'm overheating.  So I turn off the A/C and I've got a hot condition for a while but the pinging stops, and the car drives fine while I sweat in 90 plus weather.
 
Thinking about what would cause the overheating problem (although heavy city traffic is much harder on a car than highway driving), I took off the cover to the oil cooler.  This is the first time I've done this on a Corvair.  There was a blanket of stuffed insulation which no doubt got sucked in from the engine lid insulation pad, which is shredding badly.  I cleaned out all the junk as best I could, removed the insulation from the engine lid, but there is still some debris in between the plates.   BTW I have the 12 plate cooler, which was installed in A/C cars.  Also of note is that I only use Mobil 1 synthetic since it is supposed to handle high temperatures better.
 
Today I got a few minutes farther before the pinging started again.  I'm planning on removing the oil cooler and making sure its oil passages are clear, and cleaning out any remaining junk between the plates.
 
One question I have is that the Chevy shop manual says to replace the seals to the oil cooler if you remove it.  Is this required?  Also, would you folks recommend an oil change even though the oil is still pretty clean, it's been superheated a few times already?
 
Another option I'm looking into is adding water injection, a fine mist into the intake when the A/C compressor is on.  That cured the pinging problem I had with my 69 and it can, in my opinion, only help keep the engine cooler on hot days with the A/C on.  I'd control it from the same relay that operates the idle-up solenoid and A/C equipment, and possibly from the dash as well (turn it on after the engine warms up).
 
Thanks for listening, any feedback would be appreciated!  Stay cool...
 
Bill Hershkowitz  66 Monza Sport Sedan 110 PG A/C