What motor do I have?

[TDPR]

Hi! I am new so go easy on me. I just bought a 57 Chevy truck that was built about 25 years ago. The guy bought a complete Firebird and used the front clip and other running gear in the truck. He could not remember the year model of the Firebird, but knew it was in the 70s.

The casting number and code, below the head are 835704 with an X5 below. I found the chart in this site and it says X5 is a 73 with 230 HP, but the casting numbers don't fit. What do I have?

Also the motor is running fine as it only has 1500 miles since it was built, but it is all factory colors etc. I would like to dress it up with chrome or alum. covers and parts. If anyone has anything that I could use I would like to try to buy it.

Thanks,

TDPR

 

[melsg5]

The X5 is a 73 from a intermediate such as a Tempest or Full Size such as a Catalina. The 835704 are the last 6 digits of the vehicle VIN that the engine originated in. You have not provided any other casting numbers in this post.