I was wondering what parts need to be changed to install a 302 crank into a 289 block. My 302 scored #4 cyl and a friend of mine has a 289 mexican block that has been thru the machine shop that he is willing to sell me

 

I found the info i was looking for in an old post. I went and checked the 289 block and it was not a mexican block so im probily better off to have mine reworked.

 

It really isn't a problem to use a 302 crank in a 289 block. The cylinder wall skirts of the 302 extend down into the crankcase a bit further to give the pistons a little more support at the bottom of the stroke, but people have been doing that swap for years with no ill effects that I've ever heard of. There's only a difference of .013 on the stroke between the two. The downside is the possibilty of accelerated piston skirt wear and increased noise.

Have your block checked though to make sure that taking it .030 over will get rid of the scoring. If the cylinder is scored then I'm sure the piston is too so you're still looking at new pistons, it might be more cost-effective to go through your block rather than buy the block from your friend. (unless he's giving you a great deal on it).