Tri-Y Headers for torque?

chryslercruiser said

Pete had tri-y's on his willys?

I like home brewed solutions... What would happen if the center two cylinders were connected, numbers 2&4, and then1&6, so there are 3 sets of 2 cylinders.. and each is connected.. then the three collectors merge into one...?

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Tri - Y on a V8 separates the 2 cylinders on each side that fire 90° apart. What a regular manifold or shorties does is allow one of the two close firing to push high pressure exaust past the closing valve of the previous cylinder. This is hot exhaust that heats and dilutes the incoming air/fuel charge and aggrivates detonation. The collector sees a long space between exhaust pulses, then a 180° followed by two 90° apart that it senses as one larger cylinder. The V8 TRI- Y does improve low and mid range torque without a major drop in high RPM. TRI - Y generally function best below 7,000RPM. If running higher RPM 4 into 1 is best.
What you refer to TRI - Y on an inline six is really 6 into 2 into 1, and functions similar to 4 into 1 V8. In each secondary the firing pulses are 240° apart, so the exhaust does not interfere with the other 2. In the headers in the photos, I would not wish to hazard a guess on pulse tuning effectiveness. Primary tube lengths are not as important as the collector length and the "open air" volume to create the reversal for pulse tuning.