Greetings . . .

This online source suggests you'll probably need 89+:

C/R Octane Number
5:1 72
6:1 81
7:1 87
8:1 92
9:1 96
10:1 100
11:1 104
12:1 108
Frequently Asked Questions site

But you can never tell until you try. You may run fine on 87 with things set a little rich and no heavy full throttle loadings.

regards,
stock49

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