https://www.miataturbo.net/engine-performance-56/efr-built-motor-build-320-hp-pump-gas-limit-100344/

“I calculated out that around 320 HP to the wheels the built motor should start to see knock issues on 93 pump gas…and by around 340 HP, pump gas shouldn't be used at all; E85 seems very much needed.” - Xaendeau

“BTW - 320-340whp on 93 octane is just about the real-world limit. A little lower on CA91.” - Savington

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