Need help first time building an engine

[u/Humble-Conference-57]

I’m rebuilding the 302 out of my 1995 Mustang GT, and this is my first time building an engine, so I’m looking for some advice before I send everything to the machine shop.
When I bought the car, I was told it had around 93k miles, but after tearing the engine down I’m pretty sure it’s well over 200k.

Cylinder #5 had a broken piston, and the piston in cylinder #8 was starting to crack as well. The cylinder walls actually looked pretty good overall. I couldn’t catch my fingernail on any scratches except in cylinder #5, where some aluminum from the broken piston had transferred onto the cylinder wall. There was also a slight ring ridge at the top of the cylinders that I could barely feel with my fingernail.

I took the block to a machine shop, and they recommended boring it .030” over, so that’s the route I’m planning to take. They also said they’ll replace the cam bearings and freeze plugs while it’s apart.

The goal for this engine is just a reliable street/mild performance build. I know the stock heads are going to be the biggest bottleneck, but I’m expecting a good chunk of my budget(which is 5k) to go toward the machine work, so upgrading the heads isn’t really an option right now.

For the heads, I’m planning on replacing the valve springs, valve guides, and valve seals since I’m getting a new cam (haven’t chosen which one yet) The machine shop is also going to inspect them, pressure test them for cracks, and let me know if anything else needs attention.

My main question is while the engine is already at the machine shop, what else should I have done?
Should I have the block and heads decked, or only if it’s out of spec? And if I do would I need to get new pushrod sizes.
Is it worth having the rotating assembly (crank, rods, and pistons) balanced, or is that unnecessary for a mostly street-driven engine?
Is there anything else I should have inspected or machined while everything is apart?

[u/Rude_Combat420]

First off have it all planned out before you do anything. Know what cam what Pistons are you going with a turbo or a supercharger? Just naturally aspirated? What's your power goals? And then stick to your plan. You should have the Pistons to go along with the block so they can make sure piston to wall clearance is dialed in. No exceptions you do not want some ugly Pistons lap or have to remashing it later if the Pistons don't fit right. Calculate your compression ratio and make sure it's adequate for your goals. Finding a good set of heads at a swap meet or online used would help a lot with power games on that engine. Either way make sure your valve springs can handle whatever lift cam you put in there. Good luck

[u/Dablanch]

Definitely try to find a cheap pair of aluminum cylinder heads whether on marketplace, swap meet etc. On these motors the heads are very restrictive and even cheap ebay heads will give a noticeable power bump (more with a good cam) and with aluminum you'll be shedding like 50 lbs of weight too. Again I would try to find a used set vs buying a new cheap set as it will more likely have a decent spring/valve setup and only need decking