Isn't Jeffp making 350+ on his junkyard short block @ 8psi? Following his documentation takes the guess work out of it. Spend the money on a really good pro port job.
You might want to check your water temp gauge. With no coolant it should read ambient air temp, not the ~180 of coolant. You should have seen the temp drop drastically, buiring the needle to cold.
Jeff's intake isn't "stock" it's been exrudehoned. And I forget the numbers but is giving up a fair amount of flow from what his head can support, i.e. could can a fair amount of power if he changed intakes.
One thing not mentioned alot in the news, the more southern states it starts out as rain and freezes to ice under the snow, making it alot more slippery. Still my team in Greensboro panics over 2 snowflakes.