How to build a 13 second 340 Duster
I think it's been touched in a bunch of forums...lol. It's an evolving technology. Designing for high power on hot and fast burning (read as low octane) fuel. As far as my experience goes..designing an engine for pump gas isnt htat hard. designing a package that runs on the hairy edge of detonation while providing maximum power, when depending on the quality of "in the ground" fuel sources is. Basically, the smaller the space for combustion, and the more turbulence you can build in will yeild the most detonation resistance, regardless of octane. Factors that affect pinging and detonation are: head material, chamber design, finish, and size, piston dome design and finish, top ring placement on piston, valve type, finish, and size, spark plug type and heat range, valve seal quality, guide clearance, cylinder finish hone quality, camshaft's intake valve closing event timing, and intake type, design, and finish, and ignition type and curve setup. Alter any of those, and you can encourage, or discourage detonation and ping. In the perfect engine, you would see no deposits on the valves, chamber, or piston tops. If you see that in any form, you are giving up efficiency and power. But there are only so many ways to "fix" a design that is 50-60 years old. Over head 2 valve engines have been around that long. Look at a modern LS1 style chamber. it's very compact, wiht the spark plug pointed at the exh valve, and the exh valve area clearly defined next to the intake valve. On a Mopar, look a tthe MP Stage heads, or the Indy offerings. Those are newer designs. Still not "modern" IMO, but way beyond a set of 906s...lol. For best results, a dished piston, with the dish under the chamber which is also small and tight, will give the best resistance to detonation and power focussed on where it should be. Flat top thinking works, but you give up some efficiency again, for the benefit of better flame propogation. It's better than any raised dome design, but really, you dont want to have the flame have to travel all across the piston. You want it to burn very fast, in a small area, building maximum cylinder pressure just as the crank angle is at it's most vulnerable. It's a huge deal right now..How to keep high performance engines alive on pump fuel. And it's still under development. That's because regardless of fuel type, the physics and power production gains happen. That's why I say it's all about the complete design, and should be a huge consideration from the beginning of any buildup.