I have seen as high as 67psi setting my wastegates, Got it set at 62 now no leaks so far. Twins have been on for almost 5k miles and I have been on 3 different style dynos. I am going to get orings soon feel I have pushed my luck enough. I did re torque my stock bolts when I put the twins on. Tim

 

What do you retorque your factory head bolts to?

Service manual says 1/4 turn after 77ft-lbs. I checked mine after the gasket blew. I worked my way form 80ft-lbs up to 110ft-lbs, then quit.

From what I've been told and have read, the marine gasket and the factory gasket in our engines are the same thing now (last couple years anyway). The only way to get a thicker gasket is to get one for a 12V and then punch open the holes for cooling and oil.

 

I did mine to 116ftlbs, all mine moved about 1/8of a turn. Be careful if any turn more remove and replace that bolt with a new one. Haisleys machine said go to 116 or 118, I settled on the lower number. Use a good torque wrench and go slow, you need to reset your valves after. This does not work for everyone but they said it holds 70psi on there pulling 24v. Tim