Is 8.5 to 1 compression to low to build a 68 289 motor to 280 to 300 HP? What would be your choice of parts? The reason i ask is i have a set of good 351W heads that i want to use and then maybe post the build. I have read many theads about the 289 to 351 head swap and most were just buy aluminum heads. I agree with that and would love to do that but for some reason i just want to use my 351 heads. The problem with most of the head swaps were that you would have to change pistons to get the compression up due to the larger combustion chambers of the 351 head. Keith Black makes a nice set of pistons that would get me the 8.5 to 1. This is where i want to start, the right compression would be most important. Plus if i do this and it becomes a big failure then maybe nobody will ask if you can put 351 heads on a 289 anymore.