Hi mart and kurt
Yes I realise the wrc manifold will massively compromise the max engine performance. The zen is a 31cc tuned engine so will over power cat, so I thought the long manifold won't be detrimental, as at least it has more chance of running upright! Lower revs at top end, maybe a bit more torque with a pipe which is about 3.5cm too long!!!!
I tried to fit a [size=78%]105 manifold but the hatch would not fit without looking like like it was sawn apart, which is why I went for the wrc job.[/size]
Have not yet run engine in. Started with a 470 2 blade bronze prop. Have a 6717/3 brass will experiment with at next outing. Ran with one 1000cc bag in the starboard sponson, but have designed set up to run twin Baxter bags, one in each sponson, will try these out next outing. On strut, just using standard mono strut, again have one with bladed tip, but not yet tried out yet.
Thanks again to both of you your advice is very much appreciated.
Garry dickson