I have been rebuilding my 72 350. I decided to go with the stock pistons because I wanted to stay in the low 9 - 1 comp range. After doing some figuring it looks like I will have low 8-1. I have a chance to purchase a #1 or #2 set of heads. I believe these have 60cc comb chambers and would help a lot with raising my compression ratio. Are there any major differences between these and my 7A heads? I believe the # 1 heads have a rocker shaft and adjustable rockers but I see this as an advantage over the non adjustable. Any input would be much appreciated.

 

The rocker shafts I remember on a 64 cutlass 330 are not adjustable. I recall someone saying the rocker shafts can be replaced with the individual rockers that share a tower support but it also required using the later pushrods. Either way they still would not be adjustable with factory equipment.

Can anyone confirm if you can use the later style rocker, support and pushrods on the early 330 heads?

 

You would be better to find a set of #4 330 heads. They are made for 39deg cams and will be a direct bolt on. No pushrod interference.

 

I have a set of #1 heads if you need some. Can be picked up in Pawtucket.

 

All 1964-1972 SBO heads will have chambers in the same 60-64 CC range. Unless you have #8 heads now, you will not see a measurable difference in CR. Also, keep in mind that the published numbers are the BLUEPRINT numbers. The as-cast chambers tend to be both larger and more varied in size. That's just the way mass production is.

 

Boldsmobile,
How much would you be looking to get for those #1 heads?