So I bought an engine, and I finally got it last weekend. Found out today that its a 305 after being told its a 350. Got over being suicidal. So in addition to this unfortunate turn of events, I also got 5 sets of heads from a friend of mine for nothing. He told me that one set of the heads were high performance, high flowing 350 heads. None of them are. Not one head.... Became suicidal again. All of the heads were junk from the factory with the exception of a set of heads that are GM casting number 14022601 that are listed as being HO heads for a 305. So getting to the point, I've done much research and have come up empty handed. I have found that many people use them on their 350's, but outside of that I want to know if they are prone to cracking because I plan on rebuilding them for my new 305 (YAY!). Are they prone to cracking?
Never heard of cracking issues. You can make them into better performing heads if you've got a decent machine shop. The guy I use puts either 1.94 or 2.02" stainless valves and hardened seats into them and they really come to life. With the tiny 58cc combustion chambers and a thin head gasket you can get compression up around 9.0:1cr. Then if you go with a good cam, intake, and say a 650 Holley carb that 305 will go from around 221HP at the crank to 375 HP at the crank. I'm getting ready to do the same build on a 305 low mileage crate motor I am picking up soon. My machinist quoted me $300 to go completely through a set of small block heads to convert them, including valve guides and all new parts.
I've ran 305 heads on a few engines with no problem. They are a thinner casted head so it's over heating that kills them or make them crack. Hell I even have another set that have the camber brought out to match 4" bore. The intake valve are 1.84, thats the big deal and the small camber brings up the compretion on a dished 350 with only a head swap.
I ran those heads on a 11.5 to 1 .030 355, I had a 5 angle valve job 2.02 160 valves, .125 z28 springs,Ported them myself,Angle milled, a crane cam. I ran 12.8s in a 3500lb Camaro. They have potential.
Actually, the 601 heads have 53cc chambers, the more popular/common 416 are 58 cc. 601 heads were almost always on trucks, had 1.72 intake, 1.50 exhaust valves; same a Power Pack heads. Most rework the 416's however, with bigger valves and some port/bowl work. On a 350, it sure bumps up the C.R., but the valves/ports can't keep up, stock 601 or 416, so they need work. There are much better heads out there, but for a budget build, with someone who does most of their own work, they're usually more than adequate. Any head with "scalloped" bosses around the outer/lower head bolts, or thinner castings, will be somewhat crack prone. I have 601 heads on my stroker 305 (+.030/400 crank=334 CID). Good torque motor. And, I'm not a 305 basher, it's not a 350, but look at where the 305's in NHRA stock class cars are running. Butch/56sedandelivery.
Good to know. I was starting to get really pissed off, but now that I know that these heads aren't junk I think I will be okay. Thank you.
Just went through my stockpile (over 20 sets) of old take off heads. And it turns out I have a set of 14022601. Never really looked into them until now, anybody know what all can be done with them before I start really researching? This definitely gets me thinking about a hot little 283 my 64’ Chevelle or my 31’ Sedan Sent from my iPhone using H.A.M.B.
Scotch before you get too suicidal, you should take a deep breath. unless you are penniless you may want to think about rebuilding a 305. It will cost the same amount of money as rebuilding a 350 but you will still have a 305. Some time taking the loss is better than spending more money on what you got. Too bad you are so far away from me I have enough parts to build a steel crank 310" SBC. Pat
Scotch you didn’t say what you paid fo the engine.... if it was a “good deal” that may have been the reason.
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