Re: Dyno results / ? fuel-octane
I agree with Steiner, he knows his stuff.
For internal combustion engines running regular fuel you should run just about the minimum octane rating you can at the pumps which is 85 if your dynamic compression ratio is low enough to run it. You have only 9:1 static with a 383, the stroke does bump up your dynamic, larger cams do "act" smaller in larger ci motors because of the stroke, but even with a 282 and a 9:1 383 assuming the ABDC on the card is around say 67-69 you should be at or around 7.99:1-8:1 (with your aluminum heads you can actually run more dynamic and not be affected as much since they get rid of heat) dynamic which is well below needing even 93 and especially higher octane race fuels. It may not hurt to add 91-93 if you can find it, but if it runs fine on 87, it should make more power since it takes less power to ignite, which is why higher compression ratio motors need higher octane fuels because the lower the octane, the easier it is to ignite.
Race gas may be cool to buy, and smell cool coming out, but if your dynamic is low enough, you're only wasting money, and actually losing power.
Hope this helps.
Also, 465 hp is plenty to be happy with, and more than enough to power the car up steep grades in high gear.
The only Mustang I'd ever own is a Fender.
'68 333" Camaro
'14 5.0 Mustang