Fuel & Octane Question

[TJCallahan@domain.elided]

Hate to start up an old thread again, but I need some info on fuel and octane.

I'm headed out this Friday to an NWARC track event where I'll be flinging my 
"Alfa" Jetta around the cones. (Around the cones, AROUND the cones!)

This is the Jetta that just clocked 250k on the original engine. While it's 
still strong and fun, it is a little tired. The Jetta runs fine on the middle 
grade octane fuel (89) available from local stations. I do my daily driving 
in this car and much of it is "spirited" - we see redline regularly. There is 
no knock or ping from the 89 fuel and that octane is the recommended value in 
the owner's manual.

At the track event on Friday, I plan to drive with a little more passion than 
usual. Will I need extra octane (premium), or should I tank up on the usual 
stuff?

I'm thinking that the usual stuff should suffice since I'm not changing the 
tune of the engine (which has an electric motor attached to it -- the 
starter!). 

Any advice from the collective wisdom?

TIA and ciao

Tom
'63 Spider
'86 "Alfa" Jetta
Seattle

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