Is there really a difference in the flow between a '55-'56 and '51-'54 Twin H Intake?

50C8DAN
50C8DAN Senior Contributor
I have been looking at both the early Twin H and the latter Hash Twin H and the only real difference I can see between them is the early has an external balance tube and the latter has it internal.  I have always heard the early was a superior design and the later design was modified due to the inability to adjust valves in the Nash body.  So is there really an internal difference that matters?

Comments

  • bob ward
    bob ward Senior Contributor
    There is no internal difference that matters.
    The 308 with Twin H was too wide for the Hash engine bay which was designed without the 308 in mind. The internal balance tube manifold is narrower than the earlier variety and was a necessary mod to get the engine to fit.
  • 50C8DAN
    50C8DAN Senior Contributor
    thanks Bob that is what I was starting to believe after looking at all the photos I have of the two types.
  • ratlee2
    ratlee2 Expert Adviser
    Both will fit in a 53 Hornet if you use the exhaust manifold from the same year as the manifold.  I have a 55 motor with twin H in my Hornet now.  Other than a slight modification to head pipe where  it meets the exhaust manifold, the fit is good.
  • 50C8DAN
    50C8DAN Senior Contributor
    Not concerned about the exhaust.  I will be using a 55 - 56 Twin H as the starting point for the new manifold design.  There will not be a heat riser connection to the exhaust manifold for the new design, it will be hot water heated.