where can I find out what kind of head I have laying in the shop? The numbers under the valve cover are 8873487 c171 cm11 Thanks Leebo

Are there any other numbers on the head? i cant find anything on that number

Mortec has a good listing of factory heads but that doesnt ring a bell
http://www.mortec.com/castnum.htm

Seems to me to be a "487" head made on March 17, 1971.

Look to see if there is an "X" on the head. The 487 X head is just slightly better.

The 487 is not a great head but better than some from the early to mid 1970s.

jms

The #487 Heads were the First Small Spark-plug 76cc Chamber Heads 165-170cc Runners . They where made with 1.94"/1.50" Valves . Or #487X that where used on the 1971 350-330 H.P LT-1's With 2.02"/1.60" Valves and Screw in Studs with Guide Plates . They are Low C/R Heads But not smog Heads . When used with Small Domed Piston they can make good H.P . I have a set on the Bench . The Ports are just as Large as the #461-462-186 Camel Hump Fuelly Head's .

they are the #487 not the #487x. Whould they benefit a 84ho 305 engine?They are ready to be bolted up.

The airflow isn't enough better to make up for the loss of compression. At this point, see if you can scrounge up a 350 shortblock to slap them on. With flattop pistons with valve reliefs but no dish, your compression on a 350 would be between 9.0:1 and 9.5:1, depending on a few details like choice of head gaskets.