Awhile back i converted my 27 inch Dunlap tunnel hull which was powered by a OS .21 NITRO engine to 4s lipo power with a 2030 kv bl motor mounted on a K&B LOWER UNIT i inserted a 5/8 inch spacer on the transom for proper inset and set the prop c/l 5/16 of an inch above sponson bottom with X442 prop with 0 degree thrust angle while the boat runs down the straights i notice the bow porpoising lifting up and down i tried a 1/2 degree down thrust and it was even worse and moving the lipo back and forward to change c.o.g did not make any difference . What can i do to try to solve this issue ! With the nitro set up this tunnel hull ran like an outrigger. Regards Andris Golts.