Well where to start....
On the blaster I have a question for you: Is this ski still oil injection and if not, what's the ratio you're running?
For the ZXi, it could either be an extreme lean condition or an air leak. I'm almost positive it's an airleak though. To find its location you're goin to need to pressurize the case and intake to a few psi and spray a soapy water solution on to it. Where the bubbles form is where the air is leaking from. This is easiest to do with the engine removed, it's gonna be pretty difficult to get to some of the possible leaks with the engine still in the hull.
Best way to pressurize the engine is to place pieces of rubber between the throttle body and intake manifold, and then another piece between the exhaust manifold and the cylinders. Just use a small tire pump to put about 10 psi into the engine once its sealed.
On the blaster I have a question for you: Is this ski still oil injection and if not, what's the ratio you're running?
For the ZXi, it could either be an extreme lean condition or an air leak. I'm almost positive it's an airleak though. To find its location you're goin to need to pressurize the case and intake to a few psi and spray a soapy water solution on to it. Where the bubbles form is where the air is leaking from. This is easiest to do with the engine removed, it's gonna be pretty difficult to get to some of the possible leaks with the engine still in the hull.
Best way to pressurize the engine is to place pieces of rubber between the throttle body and intake manifold, and then another piece between the exhaust manifold and the cylinders. Just use a small tire pump to put about 10 psi into the engine once its sealed.