The final countdown

[Shanks12]

Bullets... I've also heard that the X-Pipe > H-Pipe

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From Article

Crossover Test Results:
By reviewing the data in figures 8-10 (below), it can be seen that when comparing the H and X types, the X crossover not only reduced 60 foot times and quarter mile times but increased trap speed as well. Functionally, the difference between the X and the H is, the X type forces the exhaust to cross between both sides. Based on the performance increases we noted with the X crossover, the scavenging forces created by the gasses crossing over in this way appear to be stronger and more effective across a wider range of engine speeds.
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Fig.8

Fig. 9

Fig. 10