Test day #2 went okay. I drilled my main jets out a little and the engine responded well. I also stepped my charger pulley size down. Now running 10 psi the boat flies to 40mph where its wayyyy over reving the whole unit. My plan is to step up my prop size and go with a stainless at the same time. There was some cavitation out of the hole for sure with the aluminum 17p that's on there.
However it did manage to spit the head gasket out on the intake side. I had adjusted the timing to far advanced and opened the throttle with a bang. I did manage to drive it back to shore chugging along. Engine temp didn't climb at all so I think it will be an easy fix... maybe 7-8 psi will be a better final setting lol. I also lost my phone and video of this thing going.
What a difference, I have no doubts it will hang with my friends v6 once I fine tune things. With 10 or so holeshots and maybe 1 hour of total run time on high boost it only had sign of failure just after I literally moved the distributer trying to gain. I heard it ping but I just wasn't fast enough to backoff the throttle. A boost retard timing box might help it fire up as with the timing retarted I noticed that it had a hard time idling while engine was not fully warmed up...
also thinking while the heads off I'm going to do valve seals. Boats been smokey on startup after siting for years now.
stack 2 head gaskets?
arp head studs available?
boost retard timing box.