O.k. I did a 2.8 to a 305 swap and the thing will sit and idle all day but if I try to drive it it dies once I get to about 35 or 40 and then I have to let it sit for a min or two befor it will start up again??It acts like its not getting any power spark.Dose anyone know how I can fix this??

 

Go for a drive and as soon as it dies, jump out and see if you are getting spark and if you have fuel pressure. That should make it easier to diagnose.