i have heard that these are good heads for a 305 is this true and are they really 55cc

 

Yes they are a decent set of heads for a 305. The reason everyone thinks these heads are so great is because of there potential. If you have them cut for 1.94 and 1.6 valves and do some porting they can easily flow as well as vortecs. Oh and I dont know if they are 55cc I thought they were 58cc. Also i believe that the 416 heads that came on Lg4 and L69 cars are the same as the 601's they were just made for pre 85 intakes. Someone correct me if I am wrong.

 

My machinest actually measured a few set's of 601's they tend to be around 55cc as 416's are 56-60cc in stock form. Either work well but if you already have a set of 416's there will not be a difference in just swapping over the 601's.

 

Both 416 & 601 are '86-earlier intake bolt and perimeter bolt cover types.

081 are the '87-later and center bolt cover design.

If you need to know what chamber volume you have for CR calculation, the only way to know for sure is to measure. Too many stories out there about chambers being larger or smaller than published. Last year the guy who assembled my heads for me showed me a set of BBC castings that are listed at 106cc that he measured at 96cc after porting/polishing.