Can someone tell me what the advantage of the '848' cyl head for the 235 cid engine is? I remember reading an article that said it was one of the best heads for beefing up the 261 (vent holes added), but it didn't say why. Is it higher compression, bigger valves - or what?

The combustion chamber is smaler, which raises the compression slightly is all.

What is the difference in the compression? I have a 54 head that needs rebuilt, and a 61 848 head that was sitting in a field for about ten years uncovered. I havent got it cleaned up yet, but wonder if its worth the time.

It's about 0.5-0.8 more than the 261 head when used on a 261 block. The 848 head has better ports than the '54 head too.

Cabbie, A good stock 235 head is around 7.5:1 and an "848" head is around 8.0:1. Either head can be selectively milled, but will require recessing the valves. If you find that your dirty "848" head checks out ok, just have it surfaced milled...no valve recessing needed... and you'll have 8.0 to 8.2 compression ratio. Perfect for the street.

check the post in performance and click on 848 porting. there is a link there that will take you to a '55 article on the test they ran on the 261 and 848 heads. Great article.The only problem is 50 years ago 18.00 could buy a corvette split exhaust and I just paid 500.00 .boo hoo LOL

The 848 head has a diffrent alloy steel which has a higher nickel content and less prone to cracking.