408 build

autoxcuda said

What tire diameters/sizes are you guys running that are suggesting rear end ratios?

1stgen, What octane of gas are you planning to run. Not sure 10.9:1 is going to run off pump 91 octane.

Notice dragfish runs 9.5:1

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Gas octane in the UK and Europe is Research Octane Number (RON), not the average of Research and Motor Octane Numbers that we use in the US, which gives us our lower-appearing octane numbers. 1stgen's octane of 95 is similar to 90-91 octane in the US, and if he can get 98 octane, that is similar to 93 octane in the US.

Just running some numbers on the Dynamic CR, starting with a 10.9 static CR and making an educated guess on the advertised duration of the Hughes cam being around 298* (which is the .050" duration + 52 degrees) gives a DCR of 8.2-8.3..... With his AL heads, I think that is manageable, but needs proper attention to tuning. I have run iron heads, with quench, at 8.3 DCR on 93 US octane, but had to limit total timing some.

Hopefully, he has set up the gasket selection and piston deck height to get some quench, which will help. Maybe he can share that info.