76_cutty

hey guys im sure i have a 350 sbo but im wondering if i can get some better heads than what it came with it?

block# 885558 2
head# 8

as i understand some of the older heads are better for performance, witch ones are the best? also if i swap them will it still smog?

thanks guys

olds425

#5's are supposed to be the best stock ones, they have a smaller combustion chamber to raise compression. I am not sure about it smogging but I can't think why not

76_cutty

got you, i wonder if i can just have these modified by a machine shop or would my money be better spent re-building some #5 heads? ^^^^BTW nice salmon!

67 Cutlass Freak

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This ID chart should help. What are your goals or budget? The #5 heads were good but not the smallest combustion chamber. Do you want or need hardened seats? For the best performance, if your going to upgrade your heads you should consider a better cam, intake & carb to match. If your engine is a high mileage unit you may want to consider a complete rebuild. A lot of people make the mistake of improving their top end to increase performance only to have the bottom end go south shortly after. Finally you should contact someone that specializes in Olds like Jim (Colormegone) from J&S Machine he can steer you in the right direction & may have a set of ported heads ready to go. Here's his website -
http://www.jsmachineoldsmobile.com/home.html
I have a bunch of core heads but last time I shipped it was close to $65 a piece. Keep us posted on your progress.

76_cutty

^^^thanks alot for the info, i am actually a ways off from doing a re-build (shes still running strong) i just wanted to know what i should keep an eye out for when going thru the junk yard. if i come across a good deal i dont want to pass it up.

im working on the interior right now, hope to have some pics soon!

joe_padavano

Actually, that block casting number is 385558 2, which is a generic 1968-1976 350 casting. The #8 heads were used from 1973-1976.