I had the inlet manifold off today to fit Barry's fuel rail kit (see sticky). While it was off I noticed that the inlet pipes for the front bank were BLACK, were as those for the rear were reddish brown.

Does this mean anything?

remember that each bank ex-factory has different plugs in it, and the front bank tends to get changed more often. Sounds like someone may have changed the specs on your front set. Personally I fundamentally didn't like this juxtaposed plugs idea and went all Iridium - and when I pulled the intake plenum to fit Barry's Rings last weekend all inlets were the same brownish colour.

I had a look at the fronts. They are new Champions. I checked the website and they are the right ones. Maybe the old ones were just plain rooted.