Stroking a Mexico 289 or newer roller 302

[MaryJaneTheMustang]

FIrst time post here.

I bought a well restored 65 mustang this summer and seeking more power and bigger smiles. I want to know what you all would do in my situation.

I want more power and torque and settled on a 347 stroker and aiming for NA 425 hp. Will probably go with AFR 185 heads and keep it carburated.

The existing engine is the original Mexico block 289 that was well rebuilt and bored 0.040 over. It is in great running order and nothing wrong with it to speak of.

I also bought a 96 roller 302 and have it torn down, hottanked, magnafluxed, and ready to go.

What would you do in my shoes? I am not worried about plus of minus the cost of going from tappet to roller so don't make that argument.

I would get the 289 sonic tested to confirm its strength. It was bored 40 over instead of the normal 30 over for a typical 347 stroker.

Oh and no blueprint engines because my sons and I are enjoying the process of the build.

 

[Bullitt347]

I would wait to see what the 289 measures out at.
If it is already .040 over, the current cylinder wall wear may put the block out of reach to get the new piston to cylinder wall clearance.
Or it may check out OK.
Verify first, then make a more educated decision.