replacement block for 525SC
 

I broke a valve and cracked my block. Which blocks and heads are compatible to replace with? I am not trying to make more power I just want a reliable replacement for my damaged block and head. Thanks

1994 gen 5

You don't really anything compatible. You can use any Generation 454 with 4 bolt mains and a forged crank.
If you're getting a new block and heads, there are better ways to go than stock that won't cost any or at least not much more and make more hp at the same time.

Agree with griff...do yourself a favor and buy a 502 block...you can probably find a useable one pretty reasonable and bolt all your S/C stuff on it...my block was good when I just did my rebuild so it wasn't cost effective for me to go bigger at the time but I def left some horsepower on the table by not going to a 502....since you have to buy one anyway go 502 at least

So do I need forged pistons and forged crank? I was looking at crate motors and not sure if they would hold up. So you are saying all my accessories would bolt right on to a 502? Would I need to change the carb or ignition?

All accessories will bolt up...at most a jet change and a little tuning from the carb but I don't see why the dominator wouldn't work...ignition should work just fine as well....don't quote me on this but I believe any marine 502 will have a forged crank at a minimum...if I were you I would buy a running 502 from someone here and freshen it up with a roller cam....you are gonna be getting to the end of the limits on what your blower can do and you will most likely make less boost on a gauge but more power at the end of the day with a 502 based setup...in my opinion I wouldn't go bigger than a 502 unless you plan on upgrading the blower to a bigger unit

Stewart

the 502 mag will have forged internals if it hasn't been messed with

Would I need standard rotation or left hand?

I would not be opposed to a new long block. I am looking more for reliability than more power

well as you can see...the valvetrain is the weak link in a big block so I would spend the money there for reliability for sure...quality roller cam, lifters, and rockers....and a side effect of that reliability is power so its a win win lol