Hey folks, I have some old heads here that I might be able to put to use, if only I knew which was best for my needs. I've been putting off installing the Stealth intake and different headers on the 305 in my Cutlass since it could really use better heads while I'm in there. Another member who has given me much already offered up some 416s or 601s, but the man has provided a SUM1104 cam kit as well as sent me a rebuilt carb and has his own stuff to deal with so I've given him space. As it turns out, I've got a few good candidates for this head swap (and a few others) already in my own garage.
The 4 best options are some local 416s for $100 or mine with these casting numbers: 3947041 (similar to "Fulie"), 3785896 & 3884520 (Power Pack?), or 354434 (smaller ports/valves than 416 but some like it).
I've read that the 041s have either 60 or 64 cc chambers and are similar to a 186 or 492. They're currently on an engine on a stand so I haven't measured the valves, which are apparently too large anyway at either 1.94 or 2.02. These are not my preference for this 305.



The 434s have 1.72 valves (measured) and I think 60 cc chambers. They came on an engine in an '85 Suburban that I bought at auction & drove around for a while so I know they work. The valves show plenty of meat, and though I've ran these before I don't know a thing about 'em- spring rate, guide/seat condition, etc..


As for the 896/ 520s, they have no accessory holes, sport 1.72 valves (measured), and the valves are pretty even with the chambers- recessed seats? 60 cc chambers? I like 'em but they seem to need more work than the 434s.



Which of those heads is best suited for a 305 in a '78 with a few lightweight items, th350 w/ 2500 stall, and a set of somewhat highway friendly gears (308/323)? Without real porting, blending, spending much $$ (Competition Products Head Improvement Kit is all I want to buy), or buying different heads. Surely one pair has better flow or burn characteristics than another and would be slightly happier with a Summit 1104 cam.

Do any of you guys with more knowledge and experience than me have any wise words that'll lead to good results?
Other heads on hand include 3 pairs of 882s, a pair of 487, and one good 487x + one obliterated 487x. The chambers or valves in all of them are too big for this.
The 4 best options are some local 416s for $100 or mine with these casting numbers: 3947041 (similar to "Fulie"), 3785896 & 3884520 (Power Pack?), or 354434 (smaller ports/valves than 416 but some like it).
I've read that the 041s have either 60 or 64 cc chambers and are similar to a 186 or 492. They're currently on an engine on a stand so I haven't measured the valves, which are apparently too large anyway at either 1.94 or 2.02. These are not my preference for this 305.



The 434s have 1.72 valves (measured) and I think 60 cc chambers. They came on an engine in an '85 Suburban that I bought at auction & drove around for a while so I know they work. The valves show plenty of meat, and though I've ran these before I don't know a thing about 'em- spring rate, guide/seat condition, etc..


As for the 896/ 520s, they have no accessory holes, sport 1.72 valves (measured), and the valves are pretty even with the chambers- recessed seats? 60 cc chambers? I like 'em but they seem to need more work than the 434s.



Which of those heads is best suited for a 305 in a '78 with a few lightweight items, th350 w/ 2500 stall, and a set of somewhat highway friendly gears (308/323)? Without real porting, blending, spending much $$ (Competition Products Head Improvement Kit is all I want to buy), or buying different heads. Surely one pair has better flow or burn characteristics than another and would be slightly happier with a Summit 1104 cam.

Do any of you guys with more knowledge and experience than me have any wise words that'll lead to good results?
Other heads on hand include 3 pairs of 882s, a pair of 487, and one good 487x + one obliterated 487x. The chambers or valves in all of them are too big for this.
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