help identifying 454
 

I have never owned or worked on a bbc. I know almost nothing about them except I’ve always wanted one and finally did. These are the numbers I was able to find.

Block: 3999289
GM10 T
B10 75
Heads: 3931063

I was told it was a 454 and I was able to hear it run & the guy even took me for a ride. It was in his 1974 Pontiac Firebird & he wanted to put the correct manufacture motor in it. It ran well. He kept the carb so I have to buy another one. Before I do I was going to see about maybe a better cam.

Was hoping someone could tell me if this is a good block/heads, what kind of hp this set up might have (ball park). I have done a little bit of reading & looks like ok heads but says they were used in 427’s from 69-70. I do know the heads have roller rockers.

I’ll be putting it in my 1954 Chevy Truck & was hoping to get about 500 hp. Any input is appreciated.