I just rebuilt the top end of my 1970 350 with vortec heads Performer rpm intake etc. So I went to start it and of course my timing was way off and the car would not start no matter where I set the distributor. So I decided maybe I have the timing off by 180 degrees, so I rewired The distributor and went to crank it over and as it felt like the engine was starting my starter cut out with a large crack, I quickly crawled under the car to remove it and found that it had cracked the casing that the gear sits in. My question is why did this happen? I assume that the starter didn't have enough torque to turn the 10.4:1 engine but I'm not sure. Btw the starter came off the 305 that was in my 78 nova... any help on finding a new starter would be appreciated also. Thanks

Depends on your flexplate size
153 tooth ( 12 1/2" ) one takes a starter with bolts inline
168 ( 14" ) one has the bolts offset
There are aftermarket starters as shown in the link that have bolt patterns to fit either size
http://www.summitracing.com/parts/SUM-829100/

Flexplate probably kicked back and cracked your starter.

If you've got a staggered bolt pattern starter (larger flexplate) I'd recommend hitting the JY and grabbing a starter off a late model truck. They're super light compared to what our cars came with stock and all over the yards. For a smaller flexplate look for an LT1 starter from a sedan. Harder to find but out there still.

If you have the $ for new order for a mid-90s Camaro or 97-99 Chevy truck.

You just broke the snout. I had a car do this in the winter once. It was a high compression 350 that barely turned over as it was. It was real cold out and the engine kicked back and broke it. The guys at the parts store were impressed. That was back when they actually knew things about cars. Be proud, it's not a common thing to do.