a good combo?

Sounds to me like it should work good as long as you have half way decent gears in it (3:23 or lower). The J heads will be lower compression but with open chambers you'll need it. I'm running a 360 with X heads and the next step up Lunati (234/242 @ .050) and compression figured in at 9.85 to 1. It won't take any more than 35 degrees of total timing without spark knock running 93 octane so I run it at 34 total to be safe. You should be about that same place with your build cause your compression should be a smidge lower than mine due to the less cubes therefore it should work about the same.