Depends on the design and depends on your definition of 'better'... tubular manifolds by design are supposed to be better than typical cast manifolds as collector design is key to power etc... tubular designs typically use merge collectors which are more effective top end than the collect designs of most cast manifolds but... if you have indeed read through the thread I posted its more that the cast mani in context has produced more power with decent EGTs and not glowing yellow like others do... the cast mani is easier to fit, will be more reliable and produce comparable or better results..
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