Re: My roller moto 302 in my z28 did a freaky thing...
 

Not a good thing. My 68 Gibb nova 427.

Re: My roller moto 302 in my z28 did a freaky thing...
 

My first guess would be the diaphragm in the fuel pump. Since you have to replace it anyway, check the diaphragm when you get the old pump off. If they sit for long periods they can drain down and dry out. Then when you crank them over they try to pump gas but it takes the path of least resistance,.... right into the crankcase.