I have recently been experimenting with a separate single carb inlet manifold that I have made for my 63 wagon. The idea is to retain the original Zenith carb and allow fitting of a twin outlet exhaust manifold. Ultimately I might go to twin SU's on the separate alloy inlet manifold I have on the shelf (I understand this would only be worthwhile if I change the cam as well).

Anyhow - what I have discovered with the separate manifold is that it takes a long time for the manifold to warm up. I have improved the situation somewhat by fitting an aluminium plate between the exhaust manifold and the inlet to help transfer heat but it is still not as good as the original one piece manifold. I have noted that the alloy manifold has what appears to be a water hose connection on it - presumably to water heat the inlet manifold. It seems a bit odd to me that there is only one connection - the water does not flow through the heating channel. It must just rely on convection to carry hot water up to this channel.

The question I have is - where do I run the water hose from? The top radiator hose doesn't make sense because the hot water won't convect downhill. Do I have to fit a tee into the steel pipe that runs under the manifolds? If anyone has a separate alloy twin SU manifold fitted - can you please post a photo and/or description of where the water hose goes.

I might end up modifying my custom inlet manifold to water heat it also - or I might just bite the bullet and go straight to the twin SU's.