octane booster

[Steve Baldwin]

Since this octane vs compression ratio thread has popped up again, I
might as well drop my question into the arena.
In New Zealand we have two available fuels rated 91 and 96 octane. Both
are lead free and the quality of the 96 is variable to say the least.
My daily clunker is an English car with 9.5:1 compression and lots of
squish. It hates the 91 octane stuff (pinking under the slightest load)
but is OK with the 96.

I also have an early 351-W with 9.5:1 compression that is slowly being
built up. The chambers are a little bit more open than the Escort so I'm
not too worried about it under normal operation.
But what happens when I squirt a couple of hundred horsepowers worth of
Nitrous into it ?
Are there any magic rules for octane margins vs nitrous ? Is the cooling
effect of the nitrous sufficient ?

It would seem a bit expensive to find out by experiment.
BANG - rebuild engine - back off half a turn - BANG - .....

Steve.