Tunnel Ram 383

greenhornet said

It's seems these T-ram threads always go in the same direction.. I'm just curious about something, How did the factory long ram engines perform? The runners are a lot longer then a T-ram plus they were in heavyass mopars.. I guess maybe high compression and a solid cam? I dunnno I've never researched the long ram set up's..

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The long rams are tuned on a different set of pressure waves. There are eight harmonics or waves in the intake tract on a V8. Each one has a unique runner length that corresponds with it's frequency, and the push the harmonic provides to the air/fuel mixture is what the long rams were designed to take advantage of. The lower the harmonic, the longer the runner length needed, and the stronger the torque is at low rpm. Long rams made huge torque with great response with moderate compression and small carbs, but the length of the runner limited horsepower and rpm potential. That's why some long rams were made shorter, and some were modified to remove the divider and shortern the effective lengths. Tunnel rams are intended to make use of the higher frequency harmonics that give a wider power curve and higher rpm potential at the expense of lower rpm performance. Which is why higher dynamic compression and rpms are generally considered required. It's all about design intent and performance window. In racing, the more firing cylinders per minute of run time, the more power gets to the tires. That's where the tunnel rams work well. They move a lot of air, which also makes them great for longer strokes.