Some 340 Questions

Fstforward said
My question, where on the heads do I find out which kind of heads it has, and what are the advantages/disadvantages of the j heads and x heads?? Shoudl I junk these heads and go for nice higher flowing aftermarket heads(as long as they are available) or sit down with a die grinder and open up the passages on these?? Also, roller lifters/rockers or flat tappet, which is a better choice??

This vehicle WILL NOT be raced, just want a nice strong engine, something decent to go to shows and cruises.

Oh well, for my first question, be gentle with me.....(8^)*

I'm sorry, that was a multi question post, you'll have to be spanked by a local Hooters girl. This will be a public floggging with a wet noodle and ladel. A wooded soup spoon may be subed in incase lental soup is being served....now on to answer your questions.

The head question. The letter series heads have there letter cast into them, one on each end by the spark plug holes.
X heads have 2.02-1.60 valves while all other heads have the 1.88 intake vale. I've been told the J's did indeed come with 2.02 valve but I have never seen it myself. Ethier way, they can be added in without issue since there the same head, just with smaller valves.

The OE iron is a good head and can do/go very far for a generally cheaper price than aluminum heads can though most aluminum heads are ment to be ported for serious power.

What is it you want to do with the engine/car and amount of power output?

On cam choice, a roller offers more. The solid cams, if choosen wisely, can stand toe to toe with a roller cam if your willing to live with a bit more spring pressure and change them out after awhile.

On rockers, I like rollers with my Hyd. cams. I'm not so keen on the noise otherwise with solid cams.