Stop and look at what this guy is asking.

First, he has a late model Camaro with a 305 in it.
Second, He happens to have a 283 block and a set of heads he is "told" are high performance. No mention of any other parts. Is it just a block, or is it a short block?
Third, He has never built an engine before.
Fourth, He wants 300-325 Ponies.

Let's analyze. If he puts a 40 year old motor into his less than 10 year old car, what will it do to the value? Will all of his modern accesories (A/C, P/S etc) bolt up to the 283 and his heads? If he is going to build a motor, the cost to build a 283 and a 350 are essentially the same cost for gaskets, bearings, rings, manifold, carb, ignition etc. To get the power he wants using the 283 plans you folks mentioned 11-1 compression, ported heads, forged crank, etc. To be able too really use that power he will need a lower gear because it will build it in the upper RPM range.

I think 283s are great motors, I built one for a Vega in 1973, it worked great! I used it because that was what I could get when I was in Germany with the USAF. But today, 350s are laying around like 283s were 30 years ago. If the guy was building a light street rod, or trying to stay period correct with a 50s or 60s car I think the 283 would be a good choice. But he is trying to get better performance out of a late model Camaro. With a 350 he will be able to use stock heads, 9-1 compression with a decent cam, carb, manifold, ignition and headers and get his horsepower in an RPM range he can use easily on the street. He should be able to build it himself with basic knowledge, following a book or with advice from friends. The motor will be easy to live with day to day on the street. And guess what, when he pops the hood, how many people are gonna know if it's a 350 or a 283 anyway? It's still a small block Chevy!

If that is "Sheeps" thinking, I guess I'm a sheep. Just seems practical to me.

Pat