steam out breather,no milkshake in pan

[RIPPINGNOLEGSKROKER]

I have a 19' Cp with a 454 ls-6 tunnel ram, iron heads and Basset thru transom headers. Last Sat went out hot lapping early, made a long pass and left bank started puking. Little bit of milk shake and alot of steam. It fluctuates with throttle input I thought it was a head gasket but there is no milkshake in the pan. What could be my problem and what should I check. Boat runs and idles fine. Thanks

[copperrat20]

Possibly blew an intake gasket?:confused:

[EliminatorJet]

I'm having the exact same problem, and i'm running the rex thermostat setup. should I back off on the ball valve (currently wide open) or install a pressure bypass?

[superdave013]

sure it's just not condensate in the valve covers?
I know when you make a pass at Lake Ming early it's like insta mike shake in the valve covers.