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Ian Harrison

Hi Chris

We have to use 99 Octane unleadead, which is what the dyno runs were done with.

We have also run MS109 unleaded, which gives great power, but is like a dry-Martini for your engine. Get the jetting wrong and it’ll end in tears!

I also test on Q16 (for the US market) and Avgas 100LL (for the Aus market).

With either of the latter fuels you can run much higher compression and ignition advance, without detonation, but I have found the trade-off between bottom-end power and over-rev renders little or no impression in terms of actual lap time.

Best Regards

Ian :-)